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.