Sunday, December 27, 2009

Meddling with sex

Your mother may have told you that it's not nice to meddle in the business of others (especially when it's 'nasty business'), but when it comes to mosquitoes, meddling may offer very nice results. Imperial College recently released a report, entitled: "Meddling in mosquitoes' sex lives could stop the spread of malaria", revealing how a particular species of Anopheles gambiae has an easily disrupted sexual process, which when interrupted will prevent that mosquito from breeding.

"The new study focuses on the species of mosquito primarily responsible for the transmission of malaria in Africa, known as Anopheles gambiae. These mosquitoes mate only once in their lifetime, which means that disrupting the reproductive process offers a good way of dramatically reducing populations of them in Africa. When they mate, the male transfers sperm to the female and then afterwards transfers a coagulated mass of proteins and seminal fluids known as a mating plug" (Reeves). Prior to the release of this study, the purpose of this mating plug was misunderstood. Unlike similar substances in other species, the "male mating plug is not a simple barrier to insemination from rival males" (Imperial). Instead it is "essential for ensuring that sperm is correctly retained in the female's sperm storage organ, from where she can fertilise eggs over the course of her lifetime. Without the mating plug, sperm is not stored correctly, and fertilisation cannot occur" (Reeves).

"In Imperial's mosquito labs, the scientists showed it was possible to prevent the formation of the plug in males, and that this stopped them successfully reproducing with females" (Imperial). "In the future", researchers may "develop an inhibitor that prevents the coagulating enzyme doing its job inside male An. gambiae mosquitoes in such a way that can be deployed easily in the field -- for example in the form of a spray as it is done with insecticides". In this way, "we could effectively induce sterility in female mosquitoes in the wild. This could provide a new way of limiting the population of this species of mosquito, and could be one more weapon in the arsenal against malaria" (Reeves).

Sources:

Imperial College London. "Meddling in Mosquitoes' Sex Lives Could Help Stop the Spread of Malaria." ScienceDaily 22 December 2009. 27 December 2009 .
Reeves, Danielle. "Meddling in Mosquitoes' Sex Lives Could Help Stop the Spread of Malaria." Imperial College London. http://www.eurekalert.org/pub_releases/2009-12/icl-mim121609.php

Thursday, December 17, 2009

Malaria in Zanzibar

Zanzibar, a" semi-autonomous region composed of two islands off the coast of Tanzania in East Africa," has "drastically reduced malaria" in the past decade. "Zanzibar's aggressive campaign against malaria has reduced infections from as much as 40 percent of its 1.2 million people to less than 1 percent." Recent concerns regarding the reintroduction of malaria to the region sparked a study that tracks the travel patterns of Zanzibar residents by their telephone reception.

"University of Florida researchers at work on a malaria elimination study in Africa have become the first to predict the spread of the disease using cell phone records." Without accessing personal information, "scientists analyzed more than 21 million calls to determine how often residents of Zanzibar travel and where they go." The researchers discovered that "short trips to Dar es Salaam on the Tanzanian mainland nearby, where malaria is relatively uncommon", dominated the travel patterns. "However, they also revealed that a few" Zanzibaris "travel back and forth from more distant areas of Tanzania where the risk of getting the disease is much higher -- posing the greatest threat to elimination."

"Most callers never left Zanzibar, which means they posed no threat of reintroducing the Malaria parasite...About 12 percent did leave the islands, but most of those only visited relatively safe Dar es Salaam, and usually for just one or two days at a time. However, a few hundred residents made trips to regions of western and southern parts of Tanzania, where as many as 40 percent of the residents have the malaria parasite."

Zanzibar has made huge advances against malaria in the past decade; however, those advancements may be reversed by reintroduction. Tanzania, including distant areas that are infected with malaria, must reduce malaria transmission in order to keep infections in Zanzibar low. With concerted effort across Tanzania, the country may eliminate malaria from within its borders.

Sources:

University of Florida. "Cell Phone Records Used to Predict Spread of Malaria." ScienceDaily 17 December 2009. 17 December 2009 .

Saturday, December 5, 2009

Eco-epidemiology

Small bands of males chased game through the savannahs. Females dug along the forest edges for roots, and searched the bushes for edible berries. Humans lived in isolated groups, which constantly moved in search of better subsistence. Then around ten thousand years ago, human settlements sprouted in the plains. Flocks grazed in pastures and humans tended their fields. This social transition "from hunting to agriculture brought permanent settlements, domestication of animals, and changes in diet. It also brought new infectious diseases, in what scientists call an 'epidemiologic transition'" (University).

"Another of these" epidemiologic "transitions came with the Industrial Revolution. Infectious diseases decreased in many places while cancer, allergies and birth defects shot up" (University). Changes to the environment, including shifts in the variety and type of species in a location, cause the emergence of new diseases or the resurgence of old diseases that were once rare.

"Now, it seems, another epidemiologic transition is upon us. A host of new infectious diseases -- like West Nile Virus -- have appeared. And infectious diseases thought to be in decline -- like malaria -- have reasserted themselves and spread" (University). Humans across the globe are falling victim to malaria, an ancient infectious disease, which was once considered to be limited to isolated tropical regions.

According to Pongsiri, a scientist conducting research on the resurgence of infectious disease, the studies "show that emergence or reemergence of many diseases is related to loss of biodiversity." She asserts that this disturbing trend is "not just case-study specific". "Something is happening at a global scale" (University). For example, it is now known that malaria rises and spreads from deforestation. The clearing of forests results in changes to the watershed, including the creation of reservoirs where malaria-carrying mosquitoes can breed. Elevation in regional temperature due to pollution or deforestation can increase the potential habitat of the mosquitoes, causing the disease to spread.

"It is new to think about biodiversity -- and therefore, species and land conservation -- as integral to public health. Until recently, almost no epidemiologists, nor medical schools, were framing questions of human infectious disease prevention in terms of, say, habitat structure, promoting genetic diversity in non-human species, or protecting animal predators as ecosystem regulators. Human diseases, goes the conventional thinking, are best understood and treated by looking at humans."

"Now there is the beginning of a movement to bring epidemiology and ecology together," says Pongsiri.

More info: http://www.sciencedaily.com/releases/2009/12/091203132157.htm

Source:
University of Vermont. "Biodiversity Loss Can Increase Infectious Diseases in Humans." ScienceDaily 3 December 2009. 5 December 2009 .

Tuesday, December 1, 2009

World AIDS Day

"Malaria and HIV are two of the most devastating global health problems of our time. Together they cause more than 4 million deaths a year" (WHO). On this World AIDS Day, Infectious Bite looks at the relationship between malaria and HIV (the virus that causes AIDS), and discusses new research to treat co-infected (simultaneously infected with both diseases) individuals.

"Our current understanding of the human immune response to malaria and HIV leads us to expect that either infection might influence the clinical course of the other." Ordinarily, "infections are associated with at least a transient increase in HIV viral load" (measure of severity) and it is logical to assume that malaria accelerates "HIV disease progression." On the other side, "immune deficiency caused by HIV infection should, in theory, reduce the immune response to malaria parasitemia and therefore increase the frequency of clinical attacks of malaria" (Whitworth).

According to UNICEF, "HIV infection increases the incidence and severity of clinical malaria. In non-pregnant adults, HIV infection has been found to roughly double the risk of malaria parasitemia and clinical malaria...Although the effect of malaria on HIV has not been so well documented, some recent research is now adding to the growing body of evidence. Acute malaria infection increases viral load, and one study found that this increased viral load was reversed by effective malaria treatment. This malaria-associated increase in viral load could lead to increased transmission of HIV and more rapid disease progression, with substantial public health implications" (UNICEF).

Treatment of malaria is also complicated by HIV. "Artemisinin combination therapy has become the standard of care for uncomplicated malaria in most of Africa. However, there is limited data on the safety and tolerability of these drugs, especially in young children and patients co-infected with HIV" (Shereen). Recently, a "controlled trial was conducted" in Uganda consisting of "HIV-infected and uninfected children aged 4-22)." Participants were randomly designated to receive treatments of artemether-lumefantrine (AL) or dihydroartemisinin-piperaquine (DP). Both therapies were deemed "safe and well tolerated for the treatment of uncomplicated malaria in young HIV-infected and uninfected children" (Shereen).

In conclusion, co-infection of HIV and malaria fuels the spread of both diseases. HIV increases the severity of the episode and the patient susceptibility to malaria infection. Malaria increases the viral load of HIV, thereby elevating the risk of spreading HIV. "Co-infection might...have facilitated the geographic expansion of malaria in areas where HIV prevalence is high. Hence, transient and repeated increases in HIV viral load resulting from recurrent co-infection with malaria may be an important factor in promoting the spread of HIV in sub-Saharan Africa" (Abu). The connection between HIV and malaria also corresponds to the treatment of both diseases. Artemether-lumefantrine and dihydroartemisinin-piperaquine are safe for the treatment of malaria in HIV-infected children. It is also believed that the effective treatment of malaria within HIV-infected individuals may reverse the increased viral load of co-infected individuals.

SOURCES:
Abu-Raddad, Laith J. Et. Al. "Dual Infection with HIV and Malaria Fuels the Spread of Both Diseases in Sub-Saharan Africa". Science 8 December 2006.

Shereen, Katrak Anne. Et al. Malaria Journal 2009, 8:272
UNICEF. "Malaria and HIV/AIDS." http://www.unicef.org/health/files/UNICEFTechnicalNote6MalariaandHIV.doc

Whitworth, James. HIV InSite Knowledge Base Chapter. May 2006. http://hivinsite.ucsf.edu/InSite?page=kb-05-04-04

WHO. http://apps.who.int/malaria/malariandhivaids.html

Friday, November 27, 2009

Pirate parasites

Parasitic Plasmodium invaders swarm the bloodstream, set up a base camp in the liver, and commandeer healthy red blood cells. These parasites "enter the body from the saliva of a mosquito" and send plague upon their victim (American). Malaria, the deadly and devastating disease that kills nearly a million people every year, is caused by the Plasmodium parasites as they pillage the human body for their own reproduction and survival.

"Inside the blood cells" of the malaria patient, "the parasites replicate and also begin to expose adhesive proteins on the cell surface that change the physical nature of the cells in the bloodstream" (American). Medical experiments "show that infected red blood cells are stiffer and stickier than normal ones." In "later stages of the disease" the cells can be "up to 10 times stiffer" than healthy red blood cells. These infected cells may also anchor onto "endothelial cells lining the vasculature, affecting the normal blood flow. This explains some of the common symptoms of malaria, such as anemia and joint pain" (American).

The parasites avoid a whirlpool of blood cell death in the spleen by anchoring in the safe harbors of the blood vessels. "Sticking to the walls of blood vessels is a survival mechanism for the parasite. In order to develop completely, it needs several days inside a red blood cell. Even though parasitized cells are nearly invisible for the immune system, they may be destroyed in the spleen while circulating freely in the bloodstream" (American).

Brown University professor George Karniadakis and student Dmitry Fedosov study "how malaria infections affect the physical properties of red blood cells, and alter normal blood flow circulation. In particular, they examine an increase in blood flow resistance, and dynamics of infected cells in the bloodstream." The properties that they measure are "used in modeling the flow of red blood cells in people infected with malaria" (American).

Fedosov says, "Our model predicts the dynamics of malaria-infected RBCs in the bloodstream, which anticipates the possible course of the disease." Each infected human contains a slightly different map and provides a unique environment that the parasites must navigate. The researchers recently discovered "that temperature fluctuations of infected red blood cell membranes measured in experiments are not directly correlated with the reported cell properties, hence, suggesting significant influence of metabolic processes" (American).

Hypothesizing on the metabolic processes that affect the patients' body temperatures, the researchers "measured an increase in resistance to blood flow in the capillaries and small arterioles during the course of malaria and found that parasitized red blood cells have a "flipping" motion at the vessel wall that appears to be due to stiffness of the infected cells. The developed models will aid to make realistic predictions of the possible course of the disease, and enhance current malaria treatments" (American).

Play the parasite game (NobelPrize.org site), and see if you can navigate your way to the liver.

Sources:
American Institute of Physics. "Measuring and Modeling Blood Flow in Malaria." ScienceDaily 22 November 2009. 27 November 2009 .

Tuesday, November 24, 2009

Call to action

"In this week's PLoS Medicine, the journal's editors call for concerted international action to address the crisis of malaria drug shortages across Africa." Compared to activism for many other causes, anti-malaria offensives are still developing to find novel ways to fight the disease. Editors reveal the signs of "an evolving 'malaria activism' (akin to AIDS activism)" (Public). "Probably no other disease in human history has been associated with social and political activism to the extent that the HIV epidemic has" (AIDS Activism). "Such activism played a huge role in reducing the costs of antiretroviral drugs in developing countries" (PLoS). Five years ago, a strong voice "argued that similar activism was needed to raise awareness of shortfalls in global efforts to control malaria" (Yarney). "We believe there are now signs of an evolving "malaria activism," which has resulted in two major successes" (PLoS). These outspoken agents assert that two waves of malaria activism have already occurred, and that we stand on the break of a third wave which will help deliver life-saving drugs to those who need them.

According to the medical journal, the "first wave of malaria activism highlighted the gap between the huge burden of malaria and the tiny amount of international development assistance dedicated to its control. Such advocacy helped motivate donors to increase their malaria commitments." The second wave of activism "focused on making sure that the extra funding was used to purchase" combination therapy drugs (like artemisinin combination therapies) that are more effective in Africa than single drug therapies (like cholorquine).
"These are big victories," the editors declare. "But one benchmark of successful ACT [Artemisinin Combination Therapy] scale-up is whether the drugs are available at the point of care. One of us has just returned from a health reporting fellowship in East Africa, where he found that ACT 'stock-outs' (shortages) were common." This crisis is due in part to "inadequate funding" to purchase the necessary combination therapies, "delays in procuring the drug, and weak health information systems that can't properly track national drug needs and flows".
The editors of the medical journal call for action. It is time for a third wave of activism. This new wave will raise awareness of the shortages of necessary drugs in regions of the world where they are desperately needed.

Sources:
AIDS Activism. http://www.albany.edu/sph/AIDS/activists.html

PLoS. "Time for a Third Wave of Malaria Activism." http://www.plosmedicine.org/article/info%3Adoi%2F10.1371%2Fjournal.pmed.1000188

Public Library of Science. "It's Time for a 'Third Wave' of Malaria Activism to Tackle Drug Shortages." ScienceDaily 23 November 2009. 24 November 2009 .

Yarney, G. "Roll Back Malaria." http://www.plosmedicine.org/article/findArticle.action?author=Yamey&title=Roll%20Back%20Malaria:%20A%20failing%20global%20health%20campaign.

Wednesday, November 18, 2009

Male infertility

How does male sterility combat malaria? When mosquitoes are sterile, they devastate the entire mosquito population. Called the Sterile Insect Technique (SIT), "the release of sexually sterile male insects to wipe out a pest population" is suggested as a "solution to the problem of malaria in Africa" (BioMed).

Malaria "control in sub-Saharan Africa, where 90 percent of the 300 to 500 million malaria cases and one to three million deaths occur from malaria each year, still depends on only two technologies for vector intervention: indoor residual spraying and insecticide-treated bed nets" (Klassen). Overtime mosquitoes become resistant to pesticides and insect populations bounce back from elimination efforts. According to researcher, Mark Benedict, "In the context of elimination, SIT could play a unique role. As part of an area-wide integrated pest management programme, the SIT may be able to minimize problems due to insecticide resistance to antimalarial drugs" (BioMed).

This technique "involves the generation of 'sterile' male mosquitoes, which are incapable of producing offspring despite being sexually active. Because female mosquitoes only mate once during their lifetimes, a single mating with a sterile male can ensure that she will never breed" This leads to an increasing reduction in the population over time, in contrast to insecticides, which kill a certain fraction of the insect population" (BioMed).

Considerable "research and development on the suppression of mosquitoes with the sterile insect technique (SIT) was conducted from the mid-1950s to the mid-1970s"; however, "nearly all of the scientists who pioneered this approach have retired and several of the greatest have died." The resurgence of this idea is due in part to "new technologies" that are "available to support area-wide integrated pest management (AW-IPM) programmes" (Klassen).

If implemented in Africa, the sterile insect technique when combined with other measures could effectively eliminate the malaria-carrying mosquito population in Africa.

For an overview of the history of malaria and the SIT project, please read the study's introduction in the malaria journal: http://www.malariajournal.com/content/8/S2/I1

Sources:
BioMed Central. "Are Sterile Mosquitoes the Answer to Malaria Elimination?." ScienceDaily 17 November 2009. 18 November 2009 .
Klassen, Wauldemar. "Introduction: development of the sterile insect technique for African malaria vectors". Homestead, Florida. 16 November 2009.

Tuesday, November 17, 2009

New Moon -- The Twilight Saga

Hold on to your teeth, Ana Revenant is writing a blog article about New Moon. You should ask yourself: why? Then, you should realize that malaria must be involved.

Congratulations, you've cracked the code. I will do almost anything to raise awareness of the threat of malaria...even if that means promoting glittering vampires.

Malaria No More, a non-profit organization that provides malaria awareness education and relief, "is offering Twilight fans the chance to win two tickets to the early and exclusive New York City Press Screening of 'The Twilight Saga: New Moon' Wednesday, November 18th at Lincoln Center".

Excerpts from Malaria No More about their contest: [CONTEST CLOSED]

On Facebook, the contest is to recruit the most friends to join the Malaria No More Twilight Causes Page. The "Top Recruiter" will be notified via a private Facebook message. Malaria No More Causes Page: http://apps.facebook.com/causes/399734

On Twitter, the contest is to create a catchy tweet that relates a malarial mosquito to a vampire, and includes the hashtag #MNMBLOOD. The person that tweets the most interesting relationship in 140 characters and with the hashtag will be notified with a direct message. Twitter: http://twitter.com/

More information can be found on the Malaria No More blog page: http://malarianomore.org/blog/?p=2099

Enjoy the contest, and be warned: I may be lurking outside the movie theater waiting to dine on the well-marinated dinner entrees that walk into my arms. Ciao!

Monday, November 16, 2009

Malaria in Vanuatu

"Vanuatu, an archipelago of over 80 islands in the South Pacific, ranks behind only the Solomon Islands for having the highest rate of malaria infections. Malaria in Vanuatu has been getting steadily worse since the 1980s, which is why UCSF scientists are among the medical professionals working hard to control malaria in this region" (UCSF).

Malaria parasites are found in all regions of Vanuatu, and "[t]ransmission occurs from December to May. Either mefloquine (Lariam), atovaquone/proquanil (Malarone), or doxycycline may be given. Mefloquine is taken once weekly in a dosage of 250 mg, starting one-to-two weeks before arrival and continuing through the trip and for four weeks after departure." Malarone is a "combination pill taken once daily with food," the side-effects of which are "typically mild". Doxycycline "is effective," against malaria in Vanuatu "but may cause an exaggerated sunburn reaction, which limits its usefulness in the tropics" (MD Health). It is important to know that "Chloroquine is NOT an effective antimalarial drug in Vanuatu and should not be taken to prevent malaria in this region" (CDC). Malaria resistance to Chloroquine is becoming increasingly throughout the world as the parasite adapts.

"UCSF researchers, with funding from the Bill and Melinda Gates Foundation", "are conducting a large-scale household-level survey of malaria treatment and prevention practices in Vanuatu. Over 900 households on four islands (out of a total of more than 80, although only a few are populated) have participated in the study. Researchers also collected blood samples from all members of the households selected for the survey, which will permit them to link survey responses on prevention and treatment practices to biological markers" (UCSF).

For more information on the study, please visit UCSF web page.

Sources:
CDC. Malaria in Vanuatu. http://wwwnc.cdc.gov/travel/destinations/Vanuatu.aspx

MD Travel Health. 'Vanautu'. http://www.mdtravelhealth.com/destinations/oceania/vanuatu.php

UCSF. Malaria Prevention. http://medschool.ucsf.edu/news/features/public_service/20060619_Malaria.aspx

Tuesday, November 3, 2009

Vaccine trials

Raise your hand if you took note of the press release regarding the malaria vaccine to jump at the chance to announce it before me. I see you there, sitting alone, sheepishly raising your hand. Actually, I'm quite proud of you. You're paying attention, spreading the word, and enlightening the world. Raise your hand higher, be proud! Oh wait. You in the public library: Put your hand down. People can see you.

So why is Ana so late to the party? No one told me the media gods were releasing the news today. I'm not psychic, you know. Also, I was preoccupied with public transit issues. Don't ask...

Of the emails and messages I received from avid followers, these are my favorites:
Can this really be true? Yaa!
Vampire fans -- this could be a breakthough.
Look [link] Why haven't you written yet? Did you get staked?

Calm yourselves, people. I'm not hindered by the strike of a little stake. The picketing version may be a different story, however.

Now that I'm back online, let me abbreviate the news:

"A pivotal efficacy trial of RTS,S, the world's most clinically advanced malaria vaccine candidate, is now underway in seven African countries: Burkina Faso, Gabon, Ghana, Kenya, Malawi, Mozambique and Tanzania" (PATH). This vaccine is the first to be designed specifically for malaria in Africa. Trials are being conducted in seven countries and different regions "across Sub-Saharan Africa" in order "to evaluate the vaccine candidate's efficacy in a variety of settings, with diverse patterns of malaria transmission. For example, some trial sites are located in areas where there is a year-round threat of malaria, while others experience only seasonal transmission". "The vaccine profile is intended primarily for infants, as they and children under the age of five are the most vulnerable to malaria" (PATH).

Previous research "studies showed that RTS,S reduced clinical episodes of malaria by 53 percent over an eight-month follow-up period" (PATH). Phase III trials are being conducted in what is now "the largest trial ever conducted in Africa of a vaccine specifically designed for use with African children."

Sources:
PATH Malaria Vaccine Initiative (2009, November 3). World's Largest Malaria Vaccine Trial Now Underway In Seven African Countries. ScienceDaily. Retrieved November 3, 2009, from http://www.sciencedaily.com¬ /releases/2009/11/091103102248.htm

Wednesday, October 28, 2009

Antimalarial side effects

In early October, a study comparing the side effects of commonly prescribed malaria medication was conducted by a team led by Dr. Frederique Jacquerioz at Tulane University. "The review looked at eight clinical trials" of commonly prescribed anti-malarials. Both "atovaquone-proguanil -- sold under the brand-name Malarone -- and doxycycline appear to have fewer side effects" than the other drugs tested. "With these two drugs, there is lower risk of nausea, stomach pain and other gastrointestinal side effects, and also neurological and psychiatric side effects, such as dizziness, sleep disturbances, anxiety and depression."

No drugs produced side effects that were considered life-threatening or required hospitalization; however, the investigators did discover a disturbing link between mefloquine and patient death. They uncovered "published case reports linking mefloquine to 22 deaths, including five suicides." It is important to note that "no other anti-malaria drugs have been linked to deaths when taken at prescribed doses".

Mefloquine is still an effective anti-malarial and may be safely prescribed to patients who have previously taken it without adverse effects. Doctors believe that risk of death is higher for patients who fail to take mefloquine when they should than the risk of serious side effects.

"[S]evere reactions to mefloquine are rare, noted Dr. Andrea Boggild of Toronto General Hospital in Canada, who was not involved in the study. In a written statement, Boggild said that severe neurological and psychiatric symptoms develop in just one out of every 6,000 to 10,000 people who take the drug."

In regard to antimalarial side effects, the Jacquerioz says this: "The main message is that you have to take some malaria chemoprophylaxis (preventive treatment) if you go to an endemic area". Malaria kills approximately one-million people each year, and an estimated ten-thousand to thirty-thousand travelers develop malaria annually.

"Boggild advised people who are planning a trip to a malaria-endemic area to talk with a healthcare provider who specializes in travel medicine about how to best protect themselves."

Source:
Reuters Health. " Two anti-malaria drugs have fewer side effects". Wednesday, October 7, 2009.

Saturday, October 24, 2009

The Democratic Republic of the Congo

"The people of the Democratic Republic of the Congo desperately need help. People are dying every day from diseases we can prevent and treat" (WHO, Donor). Malaria is one of the biggest killers in the Democratic Republic of the Congo (formerly known as Zaire). "Health experts estimate that each child under five years of age in DRC has 6 to 10 attacks of malaria per year. This is equivalent to as many as 100 million episodes, or even more, annually. Approximately 180,000 Congolese children under five die from the disease every year, and many others are orphaned when malaria weakens and kills their parents" (Gilliam).

"In less than five years, more than 3 million people have died - most from preventable and treatable diseases. The public health infrastructure is virtually broken down. The risk of epidemics remains high. Without international support to restore basic health care services, the humanitarian crisis in the Democratic Republic of the Congo will only continue to worsen" (WHO, Donor). The country's health system "is severely weakened with insufficient capacity to meet the needs of the population...In many areas, the health system functions as if it were private and patients cannot afford to seek assistance. Numerous private pharmacies provide drugs of dubious quality." Furthermore, most "health workers have not received salaries...for decades. Doctors have left the periphery and gone to the cities or to international agencies for employment...The health worker education system does not function anymore, and there are concerns about the staff qualifications" (WHO, Country).

Current estimates report that "6 out of 10 children do not reach their 5th birthday" (WHO, Donor). "Malaria (P. Falciparum) is endemic" in the country "and is accountable for 45% of childhood mortality. Children under five, of whom only an estimated 0.7% sleep under an insecticide-treated net, suffer from six to ten malaria-related fever episodes each year" (WHO, Country).

"With the rainy season just days away, UNICEF, along with partners including UNITAID and the World Food Program, is mobilizing the distribution of some 5.5 million mosquito bed nets in DRC. Each has been treated with insecticide and can help reduce the risk of contracting malaria for those who sleep under them at night" (Gilliam).

The people of the Democratic Republic of the Congo need your help. While Non-governmental organizations and charities are donating and distributing mosquito nets to the country, the need is still great. Visit one of the sites below for information on how you can help send mosquito nets to people in need in the Democratic Republic of the Congo. Also, visit our Help Us page for information on how you can help Infectious Bite raise malaria awareness.

Links:
Malaria No More
Netting Nations

Sources:
Gilliam, Eva. UNICEF. "Malaria campaign underway in Democratic Republic of Congo" 5 October 2009.

WHO. Country Profile: DRC. http://www.who.int/hac/crises/cod/drc_profile_dec08.pdf
WHO. Photo Gallery. [Photo]
WHO. Donor Profile: DRC. http://www.who.int/hac/donorinfo/campaigns/cod/en/

Wednesday, October 21, 2009

Genetic Diversity

"Scientists and health officials worldwide have made eradication of" malaria "a priority, with an effective and broadly protective vaccine a critical step toward that goal. Malaria -- a parasite spread to humans through mosquito bites -- is prevented by avoiding mosquito bites using bed nets or by killing mosquitoes with insecticides. The parasite is treatable using medications, although drug resistance is a relatively common problem. According to the World Health Organization, a child dies of malaria every 30 seconds" (University). Currently, "no approved vaccine for malaria" exists, but "various experimental vaccines are in development" (University). As of now, "vaccines directed against the blood stages of Plasmodium falciparum malaria [a deadly strain] are intended to prevent the parasite from invading and replicating within host cells. No blood-stage malaria vaccine has shown clinical efficacy in humans" (Takala).

"Researchers at the University of Maryland School of Medicine Center for Vaccine Development (CVD) have charted the extreme genetic differences that occur over time in the most dangerous malaria parasite in the world" (University). They "examined the extent and within-host dynamics of genetic diversity in the blood-stage malaria vaccine" and concluded that this "extreme diversity may pose a serious obstacle" to the creation of an effective vaccine.

"The CVD study suggests that developing a broadly protective vaccine for malaria may be challenging because the parasite's genetic makeup is so variable, constantly changing" (University).

Sources:
Takala, Shannon L. et al. "Extreme Polymorphism in a Vaccine Antigen and Risk of Clinical Malaria: Implications for Vaccine Development." Sci Transl Med 14 October 2009:
Vol. 1, Issue 2, p. 2ra5.

University of Maryland Medical Center. "Extreme Genetic Variability In Malaria Parasite Found." ScienceDaily 15 October 2009. 21 October 2009 .

Thursday, October 15, 2009

Malaria & Climate Change

Update on climate change as it relates to malaria (4 March 2010)

Every year approximately one million people die from malaria, and most of those are children. 350-500 million people are infected annually. This blood parasite is spread through the bite of infested mosquitoes and most frequently occurs within tropical regions. However, "malaria is an extremely climate-sensitive" disease that cannot be contained to the tropics (Patz). Medical researchers warn about the global threat of malaria in the future due primarily to climate change.

Climate change threatens to expand the mosquito's habitats, thereby spreading the disease. A joint study by the State University of New York and the Kenya Medical Research Institute showed that changes "in temperature can affect the development and survival of malaria parasites and the mosquitoes that carry them...Rainfall also influences the availability of mosquito habitats and the size of mosquito populations, the research found" (Barclay). A study conducted by Brown University researchers revealed that "an epidemic in Ethiopia was attributed to higher temperatures, rainfall and relative humidity than in previous years" (Brown).

A research team at University of Michigan (lead by M Pascual) has "documented a warming trend in the East African highlands from 1950 to 2002, concomitant with increases in malaria incidence. Moreover, their findings confirm the importance of the well recognized nonlinear and threshold responses of malaria (a biological system) to the effect of regional temperature change...For example, showing that the biological response of mosquito populations to warming can be more than an order of magnitude larger than the measured change in temperature represents a stunning finding, critical in advancing risk assessment of climate change impacts" (Patz).

[UNEP projected malaria distribution]

Outside of Africa, malaria is moving to higher altitudes and colder regions within endemic areas. "Malaria cases have been reported on the Bolivian high plateau," (Pabon). These individuals contracted the disease locally, meaning that malaria-carrying mosquitoes are now present in a region where they were previously unknown.

The US and UK are also under threat by malaria. Outbreaks of malaria within the US are not unknown, and may continue to increase as climates change. Florida and Louisiana are particularly susceptible to the disease. Across the pond, the UK reported 1370 cases of malaria in 2008. Six deaths were officially blamed on malaria (HPA). "A high likelihood of a major heat wave" may lead "to as many as 10,000 deaths, hitting the UK by 2012" warns the government (Prince). In coming years "the UK is to be hit by regular malaria outbreaks, fatal heat waves and contaminated drinking water within five years because of global warming, the Government has warned the NHS [National Health Service]" (Prince).

"The best climate conditions for malaria are a long rainy season that is warm and wet, followed by a dry season that is not too hot, followed by a hot and wet short rainy season," (Barclay). Pure global warming is not the primary culprit, instead a general shift in climate across regions is feared. Malaria is a devastating disease that infiltrates all areas of life. Epidemics destroy the health, economy, and cultural fabric of regions where malaria is prevalent.

We can make adjustments in our lives to prevent climate change; however, we also need to attack malaria to prevent its spread. Help Infectious Bite stop malaria in its tracks by supporting our cause or by donating to one of the many reputable agencies that provide mosquito nets and medicine to people threatened by malaria. Together we can Bite Malaria Back.

Sources:

Barclay, Eliza. " Climate Change Fueling Malaria in Kenya, Experts Say..." National Geographic. 9 January 2008.

Brown University. "Climate Change and Malaria". http://www.brown.edu/Research/EnvStudies_Theses/full9900/creid/climate_change_and_malaria.htm

Pabon, Cristina. Malaria spreading on Bolivian High Plains. SciDevNet.

Patz, Jonathan A. Sarah H Olson. "Malaria risk and temperature…" PNAS.

Prince, Rosa. "Malaria Warning as UK becomes warmer." Telegraph.co.uk. 12 Feb 2008.

UNEP: Map (http://maps.grida.no/go/graphic/climate_change_and_malaria_scenario_for_2050)

Monday, October 12, 2009

Hispaniola

The island of Hispaniola is the home to the countries of Haiti and the Dominican Republic. It is also one of the few remaining regions in the Caribbean with endemic malaria.



"In September 2008, The Carter Center, in partnership with the Dominican Republic and Haiti, launched a historic one-year initiative to help the two countries and their other partners accelerate the elimination of two devastating mosquito-borne infections--malaria and lymphatic filariasis--from Hispaniola" (Carter). "Lymphatic Filariasis, known as Elephantiasis, puts at risk more than a billion people in more than 80 countries. Over 120 million have already been affected by it, over 40 million of them are seriously incapacitated and disfigured by the disease." Like malaria, lymphatic filariasis is caused by a blood parasite that is "transmitted by mosquitoes" (WHO).

"The leaders of Haiti and the Dominican Republic agreed Thursday to cooperate in a campaign aimed at eradicating the last vestiges of malaria from the islands of the Caribbean by 2020. What remains uncertain is how to fund the roughly $250 million effort, which also aims to eliminate lymphatic filariasis, on the two-nation island of Hispaniola" (Bluestein). Although the cost of eradication is high, it is diminutive when compared with the long-term economic damage that is caused by these parasites. "Malaria and lymphatic filariasis are costly economic burdens, as both diseases are caused by--and create--additional poverty. An outbreak of malaria on the island in 2004 cost the Dominican Republic an estimated US $200 million in lost revenue from tourism. Since then, two transient outbreaks of malaria in the Bahamas and another in Jamaica have been imported from Hispaniola, which also is the source of several cases of malaria imported to the U.S. each year" (Carter).

Sources:
Image: Filariasis parasite. Wikimedia Commons.
Bluestein, Greg. "Hispaniola leaders aim to eradicate malaria". Associated Press. 10 October 2009.
Carter Center, The. "The Hispaniola Initiative." http://www.cartercenter.org/health/hispaniola-initiative/index.html
WHO: World Health Organization. Lymphatic Filariasis

Thursday, October 8, 2009

Poetry

"MALARIA" [trans. by Laurence Hope]

He lurks among the reeds, beside the marsh,
Red oleanders twisted in His hair,
His eyes are haggard and His lips are harsh,
Upon His breast the bones show gaunt and bare.

The green and stagnant waters lick his feet,
And from their filmy, iridescent scum
Clouds of mosquitoes, gauzy in the heat,
Rise with His gifts: Death and Delirium.

His messengers: they bear the deadly taint
On spangled wings aloft and far away,
Making thin music, strident and yet faint,
From golden eve to silver break of day.

The baffled sleeper hears th' incessant whine
Through his tormented dreams, and finds no rest.
The thirsty insects use his blood for wine,
Probe his blue veins and pasture on his breast.

While far away He in the marshes lies,
Staining the stagnant water with His breath,
An endless hunger burning in His eyes,
A famine unassuaged, whose food is Death.

He hides among the ghostly mists that float
Over the water, weird and white and chill,
And peasants, passing in their laden boat,
Shiver and feel a sense of coming ill.

A thousand burn and die; He takes no heed,
Their bones, unburied, strewn upon the plain,
Only increase the frenzy of His greed
To add more victims to th' already slain.

He loves the haggard frame, the shattered mind,
Gloats with delight upon the glazing eye,
Yet, in one thing His cruelty is kind,
He sends them lovely dreams before they die;

Dreams that bestow on them their heart's desire,
Visions that find them mad, and leave them blest,
To sink, forgetful of the fever's fire,
Softly, as in a lover's arms, to rest.

"Malaria". India's Love Lyrics. Trans. Laurence Hope. New York: John Lane Co., 1906.

Wednesday, October 7, 2009

Fungus reduces malaria transmission

"Biopesticides containing a fungus that is pathogenic to mosquitoes may be an effective means of reducing malaria transmission, particularly if used in combination with insecticide-treated bednets" (Public). Mosquito adaptation and resistance to insecticides is a major hindrance to malaria eradication. "In developing strategies to control malaria...there is increased interest in biological methods that do not cause instant" mosquito or parasite death. Instead, scientists are searching for preventative measures, which "have sublethal and lethal effects at different ages and stages in the mosquito life cycle", with the hope that these more mild approaches will be more effective in the long run than the aggressive techniques used in the past. (Hancock).

"[A]ccording to a modelling study conducted by Dr. Penelope Hancock from Imperial College London," incorporating fungal biopesticides "may substantially reduce malaria transmission rates and help manage insecticide resistance...Efficient combinations of interventions may allow each to be used at lower levels, and slow the development of resistance in the mosquito population" (Public).


Sources:
Hancock, Penelope A. "Combining Fungal Biopesticides and Insecticide-Treated Bednets to Enhance Malaria Control".

Public Library of Science. "Control Of Mosquito Vectors Of Malaria May Be Enhanced By A New Method Of Biocontrol." ScienceDaily 1 October 2009. 7 October 2009 .

Sunday, October 4, 2009

Popcorn parasite

Who would have thought that infecting "mosquitoes with a bacterial parasite could help prevent the spread" of blood parasites like malaria and lymphatic filariasis? If you guessed that it might, then you are either clever or very well-informed. For the rest of us, it is an exciting idea that may aid in "the control of...mosquito-borne parasites" (Wellcome).

Researchers have infected mosquitoes with a strain of Wolbachia, which is a bacterial parasite that infects insects and other arthropod species (Werren). The strain known as wMelPop, and nicknamed 'popcorn', can halve the lifespan of infected mosquitoes. "Mosquito-borne parasites such as the filarial nematode or the malaria parasite require an incubation period between ingestion and transmission, so only older mosquitoes" are "infective. Skewing the mosquito population towards younger individuals reduces the number of infectious insects." In the case of lymphatic filariasis, a parasitic worm that is transmitted by mosquitoes, wMelPop has also been shown to encourage "the mosquito's immune system to attack" the parasite that it hosts (Wellcome).

The 'Popcorn' strain may reduce the number of mosquitoes and the likelihood that they will transmit a parasite that is deadly to humans. Researchers are "currently looking at whether infecting other species of mosquito, such as Anopheles gambiae - the mosquito responsible for the majority of malaria infections - with wMelPop will have a similar effect and help inhibit malaria transmission as well as filariasis transmission."


Sources:


Kambris Z et al. Immune activation by life-shortening Wolbachia and reduced filarial competence in mosquitoes. Science 2009.

Wellcome Trust (2009, October 2). Parasite Bacteria May Help Fight Spread Of Mosquito-borne Diseases. ScienceDaily. Retrieved October 4, 2009, from http://www.sciencedaily.com­ /releases/2009/10/091001163601.htm

Werren, J.H.; Guo, L; Windsor, D. W. (1995). "Distribution of Wolbachia in neotropical arthropods". Proc. R. Soc. London Ser. B 262: 147–204.

Tuesday, September 29, 2009

African Leaders Malaria Alliance

"Malaria is one of the biggest killers of African children." Recently, "African leaders have begun an ambitious program to eliminate nearly all malaria deaths in Africa over the next six years." Initiated by Tanzanian President Jakaya Kikwete, the African Leaders Malaria Alliance was established "to streamline the procurement and distribution of control and treatment methods while keeping the disease high on the international development agenda" (Scott). "The international community has already donated more than $3 billion to the project, the BBC reports, adding, "The money will pay for the distribution of 240 million insecticide-treated bed nets throughout sub-Saharan Africa by the end of next year" (Nyaria).

"Africa is the continent most affected by malaria, accounting for 86 percent of all cases and 91 percent of all malaria deaths worldwide" (Henry). The statistics are sobering. "Nearly twenty percent of African women who die in childbirth" suffer "from malaria. It accounts for one-quarter of all deaths of children under five" (Scott). Every year, nearly a million people die.

The goal of the alliance "is to provide universal access to malaria control methods to all at-risk Africans by the end of next year in hopes of eliminating all preventable malaria deaths by 2015" (Scott). Ray Chambers, the Secretary General's Special Envoy for Malaria, says, "This is a massive undertaking unlike anything that has ever been done before."

Sources:
Associated Press. (via VOAnews.com) [Photo]

Henry J. Kaiser Family Foundation. "African Leaders Malaria Alliance Launched At U.N. General Assembly." Medical News Today. 29 Sept 2009.

Nyaria, Sandra. "African Leaders in Alliance to End Malaria Deaths on Continent By 2015." VOAnews.com. 23 Sept 2009.

Stearns, Scott. "African Leaders Fight Malaria." VOAnews.com. http://www.voanews.com/english/2009-09-22-voa52.cfm?rss=topstories. 29 Sept 2009.

Sunday, September 20, 2009

Infectious Bite needs your help

I'm pleased to tell you that recently Infectious Bite has received many emails from individuals who wish to help spread awareness about malaria. To those individuals: I sincerely thank you.
Infectious Bite is an awareness and education organization. You can show your support and deliver pertinent information about malaria to the public by adding one of these notes to your profile page or website. [Single click to view image. Right click, & save.]





A single dose of malaria medication costs approximately 13 cents. Unfortunately, infected individuals can often not afford or find the necessary medication. $10 buys and delivers a bed net (through MalariaNoMore, NothingButNets, or the CDC Foundation), which can protect two children nightly, and prevent them from contracting malaria.There are 350-500 Million cases of malaria annually. Each year, there are about 1 Million deaths. Most of the dead are children and pregnant women.
Show your support and encourage action with this simple note.It is estimated that Africa's annual GDP would increase by $100 Billion if malaria were eradicated. Malaria is not just a health problem, it is also an economic drain.




Malaria kills 350-500 million people each year. Per day, there are 2700 malaria-related deaths. This is a global health concern of massive proportions.
Malaria is a disease that infects all areas of life. The economies of malaria-laden countries suffers from a reduced or disabled workforce and high mortality rate. It is estimated that Africa's GDP would be $100 Billion dollars greater (annually) if malaria were eradicated.


You can also spread awareness about the devastation of malaria by purchasing and wearing an Infectious Bite t-shirt. Profits support our educational events and go to malaria relief.


We appreciate all offers for help. With your help we can bite malaria back.

Thursday, September 17, 2009

Tigecycline treats malaria

"Increasing resistance of Plasmodium falciparum to existing drugs has resulted in the search for new antimalarial therapies" (American). "A new study suggests that tigecycline, the first member of a new class of antibiotics, shows significant antimalarial activity on its own and may also be effective against multi drug-resistant malaria when administered in combination with traditional antimalarial drugs" (ScienceDaily).

"Tigecycline is a novel glycylcycline antibiotic with a broad antibacterial spectrum" (Starzengruber). This drug was "specifically designed to overcome" drug-resistant disease (American). Research showed that it was "up to 6 times more active against P. falciparum than doxycycline," a medication that is commonly used to treat malaria (ScienceDaily). "Tigecycline shows no activity correlation with traditional antimalarials and has substantial antimalarial activity on its own" (Starzengruber). Researchers hope that because of "its clinical efficacy", Tigecycline may be used "in combination with faster-acting antimalarials in the...treatment of multidrug-resistant P. falciparum malaria in seriously ill patients" (American).

There are some side-effects to Tigecycline treatment, and the manufacturers warn that it "may cause fetal harm when administered to a pregnant woman" (Wyeth). Pregnant women are particularly susceptible to malaria. Every year, approximately one million people die from malaria, and most of them are pregnant women and children. Nevertheless, the reduction in number of malaria cases in a region will improve the general health and economy of that are and help reduce the likelihood that pregnant women will contract malaria.

Sources:
American Society for Microbiology. "New Antibiotic Shows Promise in Fighting Malaria." 17 Sept 2009.

ScienceDaily. "New Antibiotic Shows Promise In Fighting Malaria." 11 September 2009. 17 September 2009 .

Starzengruber, P. et al. "Antimalarial Activity of Tigecycline, a Novel Glycylcycline Antibiotic." 6 March 2009.

Wyeth.com. Tygacil. http://www.wyeth.com/hcp/tygacil. [Photo]

Sunday, September 13, 2009

Monkey malaria

"Researchers in Malaysia have identified...an emerging new form of malaria infection" that is a "potentially deadly" strain of the disease (ScienceDaily). "Malaria kills more than a million people each year. It is caused by malaria parasites, which are injected into the bloodstream by infected mosquitoes" (Daneshvar).

"Recently, researchers at the University Malaysia Sarawak...showed that P. knowlesi, a malaria parasite previously thought to mainly infect only monkeys - in particular long-tailed and pig-tailed macaques found in the rainforests of Southeast Asia - was widespread amongst humans in Malaysia." After several similar reports, P. knowlesi has been deemed "the fifth cause of malaria in humans" (ScienceDaily).

P. knowlesi malaria is particularly dangerous because it "can easily be confused with P. malariae", a more benign form of malaria (ScienceDaily). Under the microscope, the two strains appear nearly identical, but the strains are very different in severity and deadliness. "One of the most significant findings of the study is that Plasmodium knowlesi was found to have the ability to reproduce every 24 hours in the blood -- meaning infection was potentially deadly. This, according to the researchers, meant early diagnosis and treatment were crucial" (Kounteya).

A universally low platelet count is another curious characteristic of this strain of parasite. "In other human forms of malaria, this would only be expected in less than eight out of ten cases." But, "all of the P. knowlesi patients - including those with uncomplicated malaria - had a low blood platelet count...The researchers believe the low blood platelet count could be used as a potential feature for diagnosis of P. knowlesi infections." (ScienceDaily).

"Recently, there have been cases of European travellers to Malaysia and an American traveller to the Philippines being admitted into hospital with knowlesi malaria following their return home" (ScienceDaily). This deadly strain of malaria may potentially spread across the globe and infect millions if it is not adequately treated and controlled.

Sources:
Daneshvar C, et al. Clinical and laboratory features of human Plasmodium knowlesi infections. Clin Infect Dis. 2009;49(6):852-60.

Kounteya Sinha. The Times of India. "Monkey malaria spreads to humans in South-east Asia". 11 September 2009.

ScienceDaily. In Humans. Retrieved September 13, 2009, from http://www.sciencedaily.com­ /releases/2009/09/090909103004.htm

Schweinsaffe im Tierpark Berlin (photo)

Tuesday, September 8, 2009

Herbal medicine

"An ancient Chinese folk medicine that's effective against malaria also might be a potent cancer-fighting candidate, scientists at the University of Washington say" (Hill). "A derivative of the sweet wormwood plant used since ancient times to fight malaria and shown to precisely target and kill cancer cells may someday aid in stopping breast cancer before it gets a toehold" (Harril). "Artemisia annua...has shown favorable...results" against "breast cancer and prostate cancer" (Artemisinin).

"The substance, artemisinin, appeared to prevent the onset of breast cancer in rats that had been given a cancer-causing agent." Artemisinin is "selectively toxic to cancer cells" (Harril). "The compound appears to be extremely" harmful "to cancer cells but had little impact on normal cells," according to the researchers (Hill).

"The properties that make artemisinin an effective antimalarial agent also appear responsible for its anti-cancer clout. When artemisinin comes into contact with iron, a chemical reaction ensues that spawns free radicals -- highly reactive chemicals that, when formed inside a cell, attack the cell membrane and other structures, killing the cell...The malaria parasite can't eliminate iron in the blood cells it eats, and stores it. Artemisinin makes that stored iron toxic to the parasite...The same appears to be true for cancer. Because they multiply so rapidly, most cancer cells have a high rate of iron uptake. Their surfaces have large numbers of receptors, which transport iron into the cells. That appears to allow the artemisinin to selectively target and kill the cancer cells, based on their higher iron content" (Harril). "In addition," artemisinin has already "been shown to be safe" in humans, as is evident in malaria patients who have taken the drug (Hill). Artemisnin may provide an alternative for harsh chemotherapy in some cancer cases.


Sources
:
“Artemisinin Herbal Extract Cures Malaria, Breast Cancer and Leukemia”. Associated Content. 29 March 2009.

Harril, Rob. “Malaria drug may help prevent breast cancer, study shows”. University Week. Jan. 12, 2006

Hill, Richard. The Oregonian, 28 Nov 2001 p C12.

Koresby Online. Artemisinin Annua. (Photo)

Friday, September 4, 2009

Malaria and antibiotics

Malaria is a parasite that is transmitted by mosquitoes and infects a million people a year. Since this disease is not caused by a bacterium, how is it that antibiotics affect malaria and improve the health of sickened individuals?

From 1920 to 1950, antibiotics were a widely used treatment for malaria, although medical practitioners were not entirely sure why this treatment was so effective (Butcher). In the early 1980s, it was "discovered that antibiotics ... are active as antimalarial agents" (Oronsky). More recently, azithromycin [also called Zithromax] has been used to treat malaria in Ethiopia after it was shown "to have efficacy in the prevention and treatment of malaria due to both Plasmodium falciparum and Plasmodium vivax," (Travis).

After research, scientists have hypothesized that antibiotics treat malaria because they attack the plasmodia (a protozoa) within the parasites; therefore the antibiotics diminish the malaria" (Flam). Furthermore, antibiotics alleviate the immune system of other infections that may coexist with malaria.

"The treatment may also have unintended consequences...including the inducement of antibiotic resistance" (Travis). However, the situation is further complicated by the development of drug-resistant bacteria in malaria-infested areas that have had no exposure to antibiotics.

As mysterious as the seemingly unfounded effectiveness of antibiotics on malaria in the 20th century, the unexplained drug-resistant bacteria in "remote rainforest communities in Guyana" confounded scientists (Juncosa). New studies revealed "that overuse of a drug used to prevent and treat malaria may be contributing to growing antibiotic resistance...Drug-resistant bacteria are known to arise from the overuse of antibiotics, which is why researchers were surprised to discover that they can develop in areas that do not have access to" that particular antibiotic [ciprofloxacin]. Michael Silverman, "an infectious disease specialist at Lakeridge Health Network in Ontario" says that antibiotic-resistant E. coli were more widespread in these remote Guyanese villages than in U.S. hospitals "where every second person is on antibiotics." Silverman's study showed that the patients infected with drug-resistant E.coli had been "given the drug chloroquine to prevent and treat malaria" (Juncosa).

According to Silverman, "It is very possible that the antimalarial drugs may be inducing a large amount of the antibiotic resistance that occurs in the tropics." Unfortunately, "plasmodia, the causative organisms of malaria, have developed resistance to antibiotics" as well and "at the same time, the mosquitoes that carry plasmodia have become resistant to the insecticides that were once used to control them. Consequently, although malaria had been almost entirely eliminated, it is now again rampant in Africa, the Middle East, Southeast Asia, and parts of Latin America" (MSN).

The increasing number of drug-resistant strains of malaria parasite, plasmodia, and other bacteria is another reason why an effective malaria vaccine is so important. We cannot continue treating malaria in the ways that we have in the past, for very soon, these old methods will be rendered ineffective.

Sources:
Butcher, Geoff. “Million Murdering Death.” History Today April 1998: 24-28.

Flam, Fray. “Scientists Find Weak Spot in Defense of Tenacious Malaria Parasite.” Tribune News Service November 1997: 26-28.

Juncosa, Barbara. "Antibiotic Resistance: Blame it on Lifesaving Malaria Drug?" Scientific American 21 July 2008.

MSN Encarta."Antibiotics"

Oronsky, Arnold L. Treatment of malaria with antibiotics. "United States Patent 4496549" 29 Jan 1985.

Science News. "Distribution Of Antibiotic For Eye Disease Linked To Low Death Risk Among Ethiopian Children." 1 Sept 2009.

Travis C. Porco; Teshome Gebre; Berhan Ayele; Jenafir House; Jeremy Keenan; Zhaoxia Zhou; Kevin Cyrus Hong; Nicole Stoller; Kathryn J. Ray; Paul Emerson; Bruce D. Gaynor; Thomas M. Lietman. Effect of Mass Distribution of Azithromycin for Trachoma Control on Overall Mortality in Ethiopian Children: A Randomized Trial. JAMA, 2009; 302 (9): 962-968

Sunday, August 30, 2009

Malaria Outbreak in Palm Beach, Florida

Americans living within the borders of the United States feel removed from the problem of malaria. Every so often it's mentioned in passing: Ashton Kutcher buys mosquito nets for children in Africa. The Gates Foundation makes a donation. But, this deadly parasite can infiltrate loosely-screened borders of any country. Malaria only needs to hijack the immune system of a single individual in order to start an epidemic.

In 2003, Palm Beach saw an outbreak of malaria. Victims ranged in wealth and status, profession and hobbies. All but one contracted malaria without having set foot outside the United States. "The hospital staff, inexperienced in working with the disease, failed to correctly identify the infections" (Packard 6). Health-care providers did not "consider malaria as a possible cause of fever among patients who have not traveled," but who experience "alternating fevers, rigors, and sweats with no obvious cause" (CDC). Calling it pneumonia and prescribing antibiotics, the hospitals sent the patients home, where they continued "to infect local mosquitoes" (Packard 6).

Anopheles mosquitoes (the ones that transmit malaria) swarm within the United States. "Palm Beach County was riddled with drainage ditches and canals, which were prime habitats for" mosquitoes (Packard 6). Between 1992 and 2003, "11 outbreaks" including at least twenty cases of "locally acquired mosquito-transmitted malaria" were reported to the CDC (CDC).

It only takes one infected individual to start an outbreak. Patient zero [the first case] may not show outward signs of the disease. This carrier could be on a regiment of symptom-suppressing medications, be recently infected, or even be immune to malaria.

In the particular case of the Palm Beach outbreak, the CDC "concluded that a migrant worker or international traveler might have been involved" (Packard 6). That traveler was not identified. The Palm Beach outbreak "demonstrated the potential for reintroduction of malaria into the United States despite intense surveillance, vector-control activities [vector=agent], and local public efforts to educate clinicians and the community" (Packard 6). It is impossible to prevent malaria from penetrating the US borders when so much of the world suffers heavily from this disease.

Malaria is a global disease. It will only be controlled by a united global assault dedicated to eradication.

Sources:
CDC. "Local transmission...". MMWR Weekly. 26 Sept 2003.

Packard, Randall M. The Making of a Tropical Disease: A short history of malaria. John Hopkins: 2007.

Friday, August 28, 2009

Malaria in Tibet

Rarely a soul considers the risk of malaria while gazing upon the snow-covered Himalayas. Why should one bother? Tibet's high-altitude and cold-weather eliminate malaria-transmitting mosquitoes in most regions. For this reason, many travel books and web sites declare that "there is no risk of malaria in Tibet" (NaTHNaC). Unfortunately, this is absolutely untrue.



"Malaria is endemic in Linzhi Prefecture in the Tibet Autonomous Region (TAR), but the vector [definition: agent] for malaria transmission" was not identified until recently. It is now believed that the mosquito, "Anopheles pseudowillmori[,] is the predominant malaria vector" in the region (Song). Preventative treatment "is recommended...for travel along the valley of the Zangbo river in the extreme southeast" of Tibet (MD). "Anti-malaria medication is recommended for low-lying subtropical areas", particularly "during the rainy season" (Dorje 49).

Tibet is home to the "Falciparum type of malaria," which is considered to be the most dangerous and most deadly strain of malaria. "Various combinations of drugs are being used such as Quinine, Tetracycline or Halofantrine. If falciparum type of malaria is definitely diagnosed, it is wise to get a good hospital as treatment can be complex and the illness very serious" (Dorje 58). Clearly, "protection against mosquitoes and drug prophylaxis against malaria are essential" when traveling to certain areas of Tibet, and all travelers should be aware of the risk of infection (51).

Sources:

Dorje, Gyurme. Tibet handbook: with Bhutan.

Galuzzi, Luca. Photo.

MD Travel Health. "Tibet". 28 August 2009.

NaTHNaC. "China (Tibet)." 28 August 2009.

Song, Wu. Et al. Malaria Journal 2009. "Anopheles pseudowillmori is the predominant malaria vector in Motuo County, Tibet Autonomous Region." 16 March 2009.

Tuesday, August 25, 2009

Genetically-engineered malaria vaccine

Scientists have created a "weakened strain of the malaria parasite" that "will be used as a live vaccine against the disease." This type of vaccine "has proven successful in eradicating smallpox and controlling diseases such as flu and polio" (Walter). It has already been advantageous in animal studies, and it is hoped that it will prove successful when it enters human trials (slated for early next year).

Professor Alan Cowman, head of the Walter and Eliza Hall Institute's Infection and Immunity division, said that "in developing the vaccine the research team...deleted two key genes in the Plasmodium falciparum parasite - which causes the form of malaria most deadly to humans" (Walter). "The deletions did not affect the parasites throughout most of the life cycle," but "by removing the genes the malaria parasite is halted during its liver infection phase, preventing it from spreading to the blood stream where it can cause severe disease and death" (Cowman; Walter). The photo to the left shows the parasitic cells during the liver stage (WT is normal).

The fact that the deletion of the genes "did not result in any observable defect during blood-stage replication...indicated that gene deletions did not affect the sexual stages of the parasite" (Cowman). "Although two genes have been deleted the parasite is still alive and able to stimulate the body's protective immune system to recognize and destroy incoming mosquito-transmitted deadly parasites" (Walter).

"Similar vaccines" have "been tested in mice and offered 100 per cent protection against malaria infection." Cowman "said it was hoped the vaccine would produce similar results in humans" (Walter). Whenever working with an attenuated [definition: weakened] strain of a disease, mutation is always a concern. Some people fear that the parasite will mutate to a viable form, thereby infecting individuals through the vaccine. "Professor Cowman said it was unlikely the weakened parasites used in the vaccine would regain their potency as the genes had been deleted from the genome and could not be recreated by the parasite" (Walter).

The fact that two essential genes have been deleted "make it extremely unlikely that the attenuated parasite vaccine could restore its capacity to multiply and lead to disease." The scientists believe that their "genetically attenuated parasite approach provides a safe and reproducible way of developing a whole organism malaria vaccine," which has the unique ability of being nearly 100% effective (Walter).


Sources:
Cowman, Alan F. et al. "Preerythrocytic, live-attenuated Plasmodium falciparum vaccine candidates by design." 10 June 2009.

Walter and Eliza Hall Institute (2009, August 24). First Genetically-engineered Malaria Vaccine To Enter Human Trials. ScienceDaily.

Monday, August 24, 2009

The solution with a crystalline heart

A team at McGill University (and RI-MUHC) in Montreal is scrambling to create a malaria vaccine. The researchers, lead by Dr. Martin Oliver, "may have blazed a trail towards the development of vaccine-like treatments to limit the severity of the devastating parasitic ailment" (Science).



The team's new discovery may lead to the development of a medication that stops malaria from creating the debilitating inflammation that is associated with malaria. "Inside the human body, the malaria parasite infects red blood cells where it survives and reproduces by feeding on the cells' contents. Eventually the cells burst, releasing the parasites and also a waste byproduct of their reproductive process: hemozoin" (Tiemi). Hemozoin is the "chemically inert crystalline substance produced in the digestive food vacuole of blood-stage malaria parasites" (Parasitology).

Although chemically inert, it is still a foreign substance in the body. The Hemozoin is "one way by which the immune system is alerted to malarial infection." It "activates the immune system, resulting in the production of inflammation mediators and in the high fever." The researchers believe that hemozoin "may be the missing link that explains why malaria leads to devastating inflammation and fever...The researchers believe it will be possible to familiarize the immune system to small quantities of hemozoin and diminish the inflammatory response in the event of infection, according to a principle similar to that of vaccines" (Science). Dr. Olivier explains that "Now our picture of the process that goes from infection to fever is more or less complete."

However, a final solution is not yet apparent. "Malaria is too complex to be narrowed down to one single mechanism" (Tiemi). Although the relationship between hemozoin and inflammation is important, there are most like many other mechanisms at work.

Will a malaria vaccine ever be available? It is certainly possible, but more research and development is needed before we will know for sure.

Sources:

Parasitology Encyclopedia. Hemozoin.

Tiemi Shio M, Eisenbarth SC, Savaria M, Vinet AF, Bellemare M-J, et al. Malarial Hemozoin Activates the NLRP3 Inflammasome through Lyn and Syk Kinases. PLoS Pathogens, 2009; 5 (8): e1000559 DOI: 10.1371/journal.ppat.1000559

Hempelmann, Birefringent Plasmodium falciparum hemozoin. [Photo]

Science Daily. "Towards Malaria 'Vaccine': Discovery Opens The Door To Malaria-prevention Therapies." 23 Aug 2009.

Thursday, August 20, 2009

World Mosquito Day

The 20th of August is World Mosquito Day. What are you doing to stop malaria?

World Mosquito Day was introduced in "an effort to remind the public about the continuing threat of malaria and other diseases transmitted by mosquitoes" (Mirsky). "Each year, approximately 350 to 500 million people are infected with malaria, killing 1 to 3 million people, mostly young children in Sub-Saharan Africa. Only female Anopheles mosquitoes that had previously bitten a person infected malaria will transmit the disease. Currently there is no vaccine that can provide high level of protection, and malaria parasites have evolved to resist many antimalarial drugs" (NowPublic).

Unfortunately, "it's not a day to celebrate" instead, it's "an awareness day. Ronald Ross of the Liverpool School of Tropical Medicine originated World Mosquito Day in 1897. He's the guy who figured out that mosquitoes carried the malaria parasite. He got one of the first Nobel Prizes for it in 1902" (Mirsky). By the way, he was also knighted in 1911. "Sir Ronald Ross was a British physician born in Almora, India. He had the breakthrough discovery during the dissection of a specific species of mosquito, the Anopheles, previously fed on a malaria patient. Malaria parasite was found on the mosquito and on its salivary glands" (NowPublic).

"112 years later, the fight against malaria is still on" (NowPublic). On this World Mosquito Day, motivate yourself to mention malaria and it's global threat to your peers, acquaintances, or that woman who swats at mosquito while she's waiting for the bus. Together, we can Bite Malaria Back.

Sources:
Mirsky, Steve. "Bite Back on World Mosquito Day." Scientific American. 19 August 2009.
NowPublic. "World Mosquito Day on August 20: Fight against Malaria" 19 August 2009.
Photograph by Hugh Sturrock

Tuesday, August 18, 2009

Ethiopia's epic battle against the Waba and malaria

Wäba: a mosquito that is carrying malaria (Amharic).

Does it strike you as strange that a language would have a specific term for a malaria-carrying mosquito? In a country that has seen 9 million cases of malaria per year, a distinction between malaria-infested mosquitoes and unaffected mosquitoes is necessary (UNICEF). Ethiopia is hit hard by malaria, but with tremendous dedication, the country is making advances against the disease.

"Historically, a malaria epidemic hits Ethiopia every five to eight years. The last one, in 2003-and four, caught the country unaware. Millions contracted the disease. Nobody knows how many died." Now, "Ethiopia is gearing up for an epic battle with malaria, possibly later this year. The stakes are high, with international aid agencies betting millions of dollars that the Horn of Africa's largest country can wipe out a disease that kills at least a million Africans every year" (Heinlein).

"Malaria is seasonal in Ethiopia coming after the beginning of the rainy season. September and October are usually the months that see the highest number of cases. Will there be more than usual this year? The head of USAID's malaria programme in Ethiopia, Richard Reithinger, says only time will tell, but if it is an epidemic year then some 10 million cases could be expected" (Chinnock). "Aid agencies have spent hundreds of millions of dollars trying to prevent the next outbreak" and "30,000 health extension workers" have been deployed to combat malaria by eradicating mosquitoes and educating the public (Heinlein). "Hospitals are also being put on alert and, meanwhile, the country continues with its ambitious programme to distribute 20 million insecticide-treated bednets" (Chinnock). "In a country with a doctor shortage and a mostly rural population...bednets for all, and an army of village-level health workers are the cornerstones of the strategy to beat the disease" (Heinlein).

The strategy of maintaining village health personnel and distributing anti-mosquito bednets is working for Ethiopia. "In 2005, the Ethiopian government unveiled an ambitious strategy, with donor support, to deliver two mosquito nets to every family at risk. By January 2008, 20.5 million bed nets had been delivered and a third of at-risk children were sleeping in safety... Within three years of the start of the program, cases of malaria, and death rates, had been halved" (Coghlan). With continued support, Ethiopia might just be able to make malaria a disease of the past.

Sources:
Chinnock, Paul. "Ethiopia will expand malaria control efforts." TropIKA.net. 23 Mar 2009.
Coghlan, Nora. "SMART Aid helps Ethiopia halve malaria deaths in two years." ONE International. 12 June 2009.
Heinlein, Peter. Addis Ababa. "Ethiopia Prepares for Battle with Malaria." VOA News. 20 March 2009.
UNICEF Ethiopia. http://www.unicef.org/ethiopia/malaria.html

Thursday, August 13, 2009

Malaria in Nigeria


Fatima (age of 31) has "seen five children into the world." Two of her babies have "died of malaria. When a member of her family falls ill, it is to home remedies and prayer to which Fatima turns. Living in a village in northern Nigeria that is 25 kilometres from the nearest town and without a health clinic or registered drug store, she has little choice" (DFID). [Photo from the DFID]

"Malaria is endemic in Nigeria with about 97% of the population at risk of infection" (Roll). "In Nigeria, malaria causes the deaths of an estimated 250,000 children under the age of five" and a total of 300,000 children every year (UNICEF). In 2007, there were nearly 5.5 million reported cases of malaria in Nigeria (Roll). "Malaria occurs in all parts of Nigeria, including large cities. Transmission is very intense, thus the risk of getting bitten by a malaria-carrying mosquito is very high" (CDC).

"Nigeria, with a population of 148 million, contributes a quarter of the malaria burden in Africa - 50% of the population will have at least one malaria attack each year" (DFID). Many will go unreported and untreated by medical professionals. Clinics are overloaded with the sick and many individuals cannot reach or afford medical help. Still, "malaria is responsible for about 66 per cent of all clinic visits in Nigeria. Health workers are sometimes forced to work overtime, and doctors and nurses can be on duty for over 12 hours a day. Still, women and children have to wait for hours before receiving medical consultation" (UNICEF).

"There is a lot of activity and momentum to combat malaria in Nigeria, but deadly gaps still exist. More needs to be done to prevent children from being infected and ensure access to quality malaria treatment," says Suomi Sakai (UNICEF Representative in Nigeria). Education of the local population "is an important part of UNICEF's malaria prevention work." Doctors and medical personnel must learn "how to prevent, recognize and treat malaria" (UNICEF). Furthermore, everyone needs to know how to properly protect themselves and their families from the mosquitoes that carry the deadly disease.

"However, even when people have been educated about malaria, poverty often stops them from seeking treatment. "Most can't afford the ITNs [Insecticide Treated Nets] or the ACT [Artemisinin-based combination therapy], which cures malaria," says Maryam Hashim (Wandi Primary Health Clinic).

Some level of resistance to malaria may exist in individuals suffering from blood disorders and those who have suffered "repeated attacks of malaria"; however, precautions to avoid mosquito bites should not be overlooked (CDC). Unfortunately, many misconceptions about malaria and its transmission exist. "Persons who were born in Nigeria are NOT protected against malaria, contrary to what many people think" (CDC).

"In 1998, the World Health Organization, UNICEF, the UN Development Programme and the World Bank came together in the Roll Back Malaria partnership, with the goal of halving the global burden of malaria by 2010...One of the objectives of Roll Back Malaria is to reduce malaria-related morbidity and mortality by 50 per cent in Nigeria by 2010, as well as to minimize the socio-economic impact of the disease" (UNICEF). This "intensive campaign" (lasting till December 2010) will distrubte "over 60 million nets...to around 30 million households during the campaign" (DFID). As part of this project, "over 800,000 Long Lasting Insecticide Nets and 55,000 long lasting insecticides kits for the re-treatment of mosquito nets have been procured and distributed by UNICEF in the past three years, with support from the Government of Japan" (UNICEF Nigeria).

Support Roll Back Malaria and its mission to reduce the number of malaria cases in Nigeria. You can also donate to Malaria No More to help provide mosquito nets to families who desperately need them.


Sources:


CDC. Malaria: Nigeria.

DFID [Department for International Development]. Nigeria gears up to roll back malaria.

Roll Back Malaria Partnership. Nigeria.

UNICEF. Nigeria: Together we can fight the scourge of malaria.

UNICEF. "Partnering to roll back malaria in Nigeria's Bauchi State."

Tuesday, August 11, 2009

Malaria in the UK

"Prepare for outbreaks of malaria," government agencies warn hospitals in the UK (Prince). Malaria is often considered a minor problem for the UK in modern times, but outbreaks are not unheard of and may become increasingly likely as global warming expands mosquito breeding grounds.

Hospitals must prepare for epidemics as they have been the site of malaria transmission in the past. In 1999 "two patients...contracted malaria while being treated at a hospital in Nottingham." The disease was transmitted from an infected patient in the hospital to the two other patients via a mosquito. That was "the second time there has been an outbreak of the tropical disease in a British hospital" (Malaria).

In 2008 reports of 1370 cases and 6 deaths from malaria were published in the UK (HPA). "A high likelihood of a major heat wave" may lead "to as many as 10,000 deaths, hitting the UK by 2012" warns the government (Prince). In coming years "the UK is to be hit by regular malaria outbreaks, fatal heat waves and contaminated drinking water within five years because of global warming, the Government has warned the NHS [National Health Service]" (Prince).

Malaria has been endemic in the UK before. "Malaria has been seen in these islands in the past" (Prince). "The marshlands of coastal southern and eastern England had unusually high levels of mortality from the sixteenth to the nineteenth century. The unhealthiness of the environment aroused frequent comment during this period and it was attributed to an endemic disease known as "marsh fever" or "ague"." This "marsh fever" is considered to be "malaria transmitted by anopheline mosquitoes. Malaria, once endemic in the coastal marshes of England, had a striking impact on local patterns of disease and death" (Dobson).

Malaria is present in the UK and outbreaks are not impossible. Heat waves from global warming may cause flooding and encourage mosquito breeding, but mosquito havens exist now. "The Thames Estuary has been identified as the likeliest place for a new outbreak of malaria, following an investigation by insect experts" (Thames). An outbreak of malaria may be possible even without the feared heat wave if such mosquito habitats are not addressed effectively.

"A spokesman for the Health Protection Agency said: Our work is based on what is likely to happen if we do nothing to prevent" the development of mosquito breeding grounds, "and it could well be that we see an increase in diseases such as malaria" (Prince).

The idea of a modern malaria epidemic in the UK is horrifying but preventable. "Better management and control of man-made sites where malarial mosquitoes may easily reproduce - such as water wells and bore holes - may help reduce malaria breeding close to human settlements" (Vector). Furthermore, home and land owners should take responsibility to prevent standing and stagnant water on their property. Fountains can be installed into ponds and lakes to agitate the water so that mosquitoes cannot breed. Even small amounts of standing water can serve as a nursery for the mosquitoes that transmit deadly malaria.

Sources:
Dobson MJ. Malaria in England: a geographical and historical perspective. 1994 August.
"Malaria outbreak at UK hospital" BBC. 29 March 1999.
Prince, Rosa. "Malaria Warning as UK becomes warmer." Telegraph.co.uk. 12 Feb 2008.
"Thames marshes 'perfect breeding grounds for malaria'." Evening Standard, The. 1 Feb 2002.
"Vector Control Tools..." The Health and Environment Linkages Initiative. http://www.who.int/heli/risks/vectors/malariacontrol/en/index3.html

Friday, August 7, 2009

Microchip detects malaria in Glasgow

"Scientists from Glasgow University claim they have created a device which can detect malaria within minutes." A microchip has been created to detect the malaria parasites in a blood sample. After the "blood samples are placed in the microchip" the device detects "the strain of disease. This means the best drug can be used to treat it." This method of detection is much better than previous methods because it is more accurate and faster (BBC).

"The current way of diagnosing is using a blood smear on a slide and examining it on a microscope," said project-leader Dr Ranford-Cartwright. "That will take a good microscopist a good hour to reach a diagnosis, it's extremely difficult to make that diagnosis accurately." This microchip "can give us a result in as little as half an hour."

Although malaria is less prevalent in the UK than in tropical regions of the world, it is not absent. "Last year a study revealed more cases of the most dangerous type of malaria than ever before are being brought back to the UK from trips abroad." Most malaria infections are imported, but the number of detected cases is rising. "The Health Protection Agency study identified 6,753 cases of falciparum malaria diagnosed between 2002 and 2006" (BBC).

Correct diagnosis is only one step toward malaria eradication. Another involves the development and use of effective drugs in the fight against the parasite. Ranford-Cartwright leads several research programs at the University of Glasgow including studies that examine the genetic markers for drug resistance. She says, "For this work we maintain different species of Anopheles mosquitoes in insectaries, and we infect them with P. falciparum sexual stages grown in culture. We use genetic techniques to study complex traits such as the interaction between the malaria parasite and its mosquito vector. We are also involved in work to identify factors important in the spread of anti-malarial resistance" (Ranford-Cartwright). "There is" further "need for a specific, sensitive, robust, and large-scale method for diagnosis of drug resistance genes in natural Plasmodium falciparum infections" (Abdel-Muhsin).

Sources:
Abdel-Muhsin, AM. LC Ranford-Cartwright, et al. "Detection of mutations in the Plasmodium falciparum dihydrofolate reductase (dhfr) gene by dot-blot hybridization." Am. J. Trop. Med. Hyg., 67(1), 2002, pp. 24-27

BBC News. "Doctors welcome Malaria Microchip." 24 April 2009.

Ranford-Cartwright, Lisa. "Research Interests." University of Glasgow. 7 August 2009.