“Malaria is one of the most pressing health crises of developing countries: in communities stricken by infection, attendance at work and school drops, and poverty deepens…There is no vaccine for malaria, which sickens almost a quarter of a billion people each year and kills a child every 30 seconds.” Scientists race to change those statistics, exploring various avenues for human vaccination and malaria eradication. Recently, “researchers at The Rockefeller University have genetically transformed the yellow fever vaccine to prime the immune system to fend off the mosquito borne parasites that cause the disease. The researchers found that the modified vaccine, along with a booster, provided mice with immunity to the deadly disease.”
“It has been known since the 1960s that” the sporozoite, one form of the malaria parasite “can wake up the immune system and help to protect against future infection.” Unfortunately, the only known “way to gather sporozoites…is to pluck them one-by-one from the salivary glands of irradiated, malaria-ridden mosquitoes. To provide immunity, the attenuated parasites must then be injected in high doses” or “delivered by the bites of hundreds of mosquitoes”, which is “a labor intensive approach not feasible for large-scale use.”
In an effort to find a better way to achieve the “benefits of sporozoite immunization”, scientists, led by Charles Rice, thought “that fighting infection with infection might be the key. They began experimenting with the attenuated yellow fever strain used in the yellow fever vaccine, known as YF17D, which has been used to successfully vaccinate more than 400 million people since 1937. Previous work in the Rice laboratory and by others had shown that this vaccine strain could be modified to include short sequences from other pathogens, including malaria.”
“Immunization of mice with the YF17D-CSP vaccine led to a measurable jump in immune activity against the malaria protein, but the single shot was not enough to protect the animals from infection with the mouse form of the malaria parasite.” The scientists added a booster shot, and discovered that “vaccination with YF17D-CSP plus the sporozoites protected 100 percent of the animals against infection.”
Sources:
Stoyanov et al. Immunogenicity and protective efficacy of a recombinant yellow fever vaccine against the murine malarial parasite Plasmodium yoelii. Vaccine, 2010; 28 (29): 4644 DOI: 10.1016/j.vaccine.2010.04.071
Rockefeller University (2010, June 11). Yellow fever vaccine modified to fight malaria. ScienceDaily. Retrieved June 13, 2010, from http://www.sciencedaily.com¬ /releases/2010/06/100611222839.htm
Showing posts with label infection. Show all posts
Showing posts with label infection. Show all posts
Sunday, June 13, 2010
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.
"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
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.
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.
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.
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, July 31, 2009
Malaria in Bolivia
Travel websites warn tourists to "consider taking medication for malaria prophylaxis (cholorquine, doxycycline, or mefloquine)," particularly in the areas "surrounding Santa Cruz," where "yellow fever and malaria are two common mosquito-borne diseases" (MDTravel). The CDC indicates that "areas of Bolivia with Malaria" include "all areas <2,500 m" in the regions of "Beni, Chuquisaca, Cochabamba, La Paz, Pando, Santa Cruz, and Tarija." However, the CDC also warns that Chloroquine, commonly used to prevent and treat malaria, "is NOT an effective anti-malaria drug in Bolivia and should not be taken to prevent malaria in this region" (CDC). In reality, "none of the currently available prophylactic medications is 100% effective. If travel to malarious areas is unavoidable, insect protection measures must be strictly followed at all times" (MDTravel).
Furthermore, areas above 2,500 meters are not absent of the disease. "Malaria cases have been reported on the Bolivian high plateau, confirming scientists' predictions that mosquitoes have adapted to a colder climate." These cases "were found in Oruro, western Bolivia, around 3,710 metres above sea level". Researchers have "demonstrated that some anopheles mosquitoes" (the ones that carry malaria) "have adapted to living at altitudes between 2,520 and 3,590 metres--conditions very different from their usual environment: warm, tropical and subtropical regions below 2,600 metres." Some researchers postulate that "a new subspecies has emerged." Scientists have noticed that the tails "have become shorter" and the "mosquito can live in dirty water rather than the clean water it inhabits at lower levels. It can survive" nighttime temperatures "as low as eight degrees Celsius" (Pabon) This can be terrifying news for the residents of these high-altitude regions since many do not have access to adequate health care to combat malaria.
One case study, examines the village of Tuntunani, which is "situated at an elevation of 2,300 meters." This community "experienced its first malaria outbreak in 1998". "An investigation two years later indicated that the epidemic resulted from introduced transmission...58% of the people had been ill for three weeks or longer" as a result. "This outbreak demonstrates the vulnerability of highland populations with poor access to health care to introduced malaria" (Rutar 15).
It seems that malaria is spreading in a country where its effects are already devastating. "Malaria affects over 3.5 million people in Bolivia each year. The Amazon basin regions of Beni and Pando have the country's highest infection rates. In these regions, migratory worker populations, such as castaneros" (Brazil nut farmers) "run a high risk of malaria infection"
When these harvesters "are sick with malaria, the family income drops since workers do not earn their wages and family members stay home to care for them." Estimates indicate that "at least 15,000 families from rural areas depend on this market for survival" (USAID). USAid led a pilot study among the community of Brazil nut harvesters and found that one-third of the farmers tested positive for malaria.
Pregnant women in Bolivia are also at high risk for the disease. Malaria affects pregnant women and children drastically. The anemia and fever from malaria can cause birth defects and death. Furthermore, there is no approved treatment or avoidance measures for pregnant women to take in Bolivia. Many of the prophylactic medications that work against the Bolivian strain of malaria can cause birth defects or miscarriages during the first trimester. At this time, most women find that they can only use mosquito repellent and mosquito nets to avoid contracting malaria during pregnancy.
Map of regions in Bolivia where malaria is endemic
Sources:
CDC.gov/travel/destinations/bolivia.aspx
Pabon, Cristina. Malaria spreading on Bolivian High Plains. SciDevNet.
Rutar, Tina. Eduardo J Baldomar Salgueiro, James H Maguire. "Introduced Plasmodium Vivas Malaria in a Bolivian Community at an Elevation of 2,300 Meters."
TravelMD. Bolivia.
USAID Reducing Malaria in Migrant Populations
Furthermore, areas above 2,500 meters are not absent of the disease. "Malaria cases have been reported on the Bolivian high plateau, confirming scientists' predictions that mosquitoes have adapted to a colder climate." These cases "were found in Oruro, western Bolivia, around 3,710 metres above sea level". Researchers have "demonstrated that some anopheles mosquitoes" (the ones that carry malaria) "have adapted to living at altitudes between 2,520 and 3,590 metres--conditions very different from their usual environment: warm, tropical and subtropical regions below 2,600 metres." Some researchers postulate that "a new subspecies has emerged." Scientists have noticed that the tails "have become shorter" and the "mosquito can live in dirty water rather than the clean water it inhabits at lower levels. It can survive" nighttime temperatures "as low as eight degrees Celsius" (Pabon) This can be terrifying news for the residents of these high-altitude regions since many do not have access to adequate health care to combat malaria.
One case study, examines the village of Tuntunani, which is "situated at an elevation of 2,300 meters." This community "experienced its first malaria outbreak in 1998". "An investigation two years later indicated that the epidemic resulted from introduced transmission...58% of the people had been ill for three weeks or longer" as a result. "This outbreak demonstrates the vulnerability of highland populations with poor access to health care to introduced malaria" (Rutar 15).
It seems that malaria is spreading in a country where its effects are already devastating. "Malaria affects over 3.5 million people in Bolivia each year. The Amazon basin regions of Beni and Pando have the country's highest infection rates. In these regions, migratory worker populations, such as castaneros" (Brazil nut farmers) "run a high risk of malaria infection"
When these harvesters "are sick with malaria, the family income drops since workers do not earn their wages and family members stay home to care for them." Estimates indicate that "at least 15,000 families from rural areas depend on this market for survival" (USAID). USAid led a pilot study among the community of Brazil nut harvesters and found that one-third of the farmers tested positive for malaria.
Pregnant women in Bolivia are also at high risk for the disease. Malaria affects pregnant women and children drastically. The anemia and fever from malaria can cause birth defects and death. Furthermore, there is no approved treatment or avoidance measures for pregnant women to take in Bolivia. Many of the prophylactic medications that work against the Bolivian strain of malaria can cause birth defects or miscarriages during the first trimester. At this time, most women find that they can only use mosquito repellent and mosquito nets to avoid contracting malaria during pregnancy.
Map of regions in Bolivia where malaria is endemic
Sources:
CDC.gov/travel/destinations/bolivia.aspx
Pabon, Cristina. Malaria spreading on Bolivian High Plains. SciDevNet.
Rutar, Tina. Eduardo J Baldomar Salgueiro, James H Maguire. "Introduced Plasmodium Vivas Malaria in a Bolivian Community at an Elevation of 2,300 Meters."
TravelMD. Bolivia.
USAID Reducing Malaria in Migrant Populations
Friday, July 24, 2009
Malaria in Ghana
New Release: 24 July 2009 reports prevalence of fake drugs in Ghana
Despite increased prevention efforts, Ghana is struggling to control endemic Malaria. Major roadblocks include economic deterioration, reduced effectiveness of indoor spraying & bed nets, and the importation of fake drugs to treat malaria.
In early July, US President Obama visited Ghana and "reaffirmed the United States' commitment to fighting malaria and other pressing global health needs" (Malaria Policy, President). For Ghana, the fight against malaria is one of medical and economic concern. "One infected person can indirectly infect 100 others that is how efficient the malaria mosquito is" (Afiriyie). Malaria is detrimental to the population of Ghana and the economic standing of the country. All are effected by the "debilitating effects of malaria on adult victims...In addition to time and money spent on preventing and treating malaria, it causes considerable pain and weakness among its victims. This can reduce peoples' working abilities. The adverse impact of the disease on household production and gross domestic product can be substantial. Malaria therefore is not only a public health problem but also a developmental problem." Apart "from the negative effect of lost productivity on the major sectors of the economy, malaria has negative effects on the growth of tourism, investments and trade especially in endemic regions" (Asante 8).
Every year, "huge sums of money" are "spent on malaria" treatment "even though the disease could be prevented," with the establishment of well-funded programs (Joy). Some methods of malaria control include bed-nets (mosquito nets that drape the beds to prevent mosquito bites during the night) and indoor spraying. Unfortunately, there is some indication that "Indoor Residual Spraying will never eliminate malaria in Ghana". "Hayford Siaw, Executive Director of Volunteer Partnerships for West Africa (VPWA) has expressed concern" over the investments in bed-nets and indoor spraying, saying that "The indoor residual spraying is no more effective than the bed nets, about 25% effective". Effectiveness of indoor treatment is reduced by a "genetic pre-disposition of some malaria mosquitoes" to "only bite outdoors" (Afiriyie). Still, the bed nets and indoor spraying do reduce the number of malaria cases and should not be abandoned. Other methods of eradication should be used in tandem with indoor treatments in order to effectively eliminate malaria in the region.
Ghana is working to establish and maintain programs that will diminish the mosquito population that carries malaria. "Zoomlion, a waste management company that works to improve sanitation throughout the country and fight malaria," maintains "a total of 420 'spraying gangs'" that "periodically spray mosquito breeding sites in order to stop the spread of malaria." This agency "aims to educate communities on sanitation issues and to engage young people in the cause. Their efforts have greatly improved waste issues in the region." (Malaria Policy, Ghana).
The sanitation progress is a step in reducing the "more than 3 million cases of malaria" that "are reported every year in Ghana, more than 900,000 of those cases are young children" (USAID). "45 per cent of child mortality rate recorded nationwide" in 2008 "was caused by malaria" (Joy).
International programs and various governments have stepped up to provide support for Ghana's anti-malaria campaign. It is reported that in December of 2008, China provided "medical assistance to some health practitioners in the country" of Ghana, in order to support their education about anti-malaria practices (Ghana News). In 2006 & 2007, Cuba also donated to Ghana in order to help fund the country's eradication program. Other nations have continuously provided their support to Ghana.
But, news journals have recently revealed that some anti-malarial drugs entering Ghana are fake. "Quantities of a prescription medication used throughout the world for treating malaria have been identified as lacking any active ingredient and presumably counterfeit. These are being removed from the market in Ghana, where they were discovered recently and confirmed as fake last Friday" (Pierson).
The drug (sold as Novartis Coartem{R}) lacked the ingredients necessary to effectively treat malaria. "This drug is an artemisinin-based combination therapy" and it is "recommended by the World Health Organization (WHO) for treating "uncomplicated" malaria" (Pierson).
"It has been estimated that up to 15% of all sold drugs are fake, and in parts of Africa this figure exceeds 50% , which paints a grim picture of health delivery in Ghana and elsewhere in Africa. China is emerging as a source country of counterfeit drugs. India and other Asian countries are" also "emerging as sources"(Ghanian).
"A major barrier in combating malaria throughout much of the developing world is the widespread presence of counterfeit and adulterated drugs, which undermines the public health. Not only do these drugs fail to deliver the appropriate treatment to individual patients--putting their lives at risk, but they contribute to the growth of drug-resistant strains of malaria, one of the greatest challenges to malaria control today" (Pierson).
"The FDB [Food & Drug Board] knows more than anyone that the drug counterfeit business is a multi-million dollar business globally, which is gaining roots in Ghana, the emerging gateway to everything...The production of substandard and fake drugs is a vast and under-reported problem, particularly affecting poorer countries. It is an important cause of unnecessary morbidity, mortality, and loss of public confidence in medicines and health structures" (Ghanian).
"Mr. Anthony Ofori, Brong Ahafo Regional Co-coordinator of Malaria Control," requests "effective collaboration between non-governmental organisations (NGOs), corporate bodies and the health authorities in the campaign against malaria in the country" (Joy). Malaria is endemic throughout the entire country (See map). Ghana is in dire need of positive international assistance in the war against malaria.
Note About Malaria:
"Malaria is integrally tied to maternal and child health in Africa." Each year pregnant women and children suffer and die from the infectious parasite. "Effective malaria control programs" are "vital to helping health systems adequately care for mothers and children," (Malaria Policy, President). "The effect of malaria on people of all ages is quite immense. It is however very serious among pregnant women and children because they have less immunity" (Asante 7).
A Note about Donations:
If you would like to donate to the cause, please visit the Malaria No More site.
At this time, Infectious Bite is not accepting donations. Please donate directly to a reputable agency.
Sources:
Afiriyie, Constance. Volunteer Partnerships for West Africa. "Indoor Residual Spraying will never eliminate malaria in Ghana."
Asante, Felix Ankomah. Kwadwo Asenso-Okyere. Economic Burden of Malaria in Ghana.
Ghanian Journal, The. "Let's do away with fake drugs". 24 July 2009.
Ghana News Agency (via fmprc.gov). China donates anti-malaria drugs to Ghana.
Joy Online. Ghana needs effective collaboration in malaria campaign.
Malaria Policy Center: President Obama Visits Ghana and Reaffirms U.S. Commitment to Fight Malaria.
Malaria Policy Center: Ghana fights malaria by improving sanitation.
Pierson, Francine. US Pharmacopeia. "Counterfeit Antimalarial Drug Discovered in Ghana with Aid of USP Drug Quality and Information Program". 22 July 2009.
USAID Press Release. USAID Administrator Tours Ghana Malaria Control Center.
Wednesday, July 22, 2009
Halting Malaria Transmission
Brought to my attention by @sarahsearle
"Researchers at the Johns Hopkins Malaria Research Institute have for the first time produced a malarial protein" that can "generate a significant immune response" and be used to create "a potential transmission-blocking vaccine" (Parsons). Antibodies produced in response to the protein, inhibit the "sexual development of the malaria-causing parasite, Plasmodium, as it grows within the mosquito".
"According to the study, a single-dose vaccine provided a 93 percent transmission-blocking immune response, reaching greater than 98 percent after a booster was given several months later" (Parsons).
Humans are on the verge of successfully creating a vaccine that may inhibit the spread of malaria. In the late 1980s, scientists understood the possibility of transmission-blocking immunity. They discovered that individuals can "develop immunity that suppresses the infectivity of the sexual stages of the parasite." This "immunity is antibody mediated and is directed against the parasites in the mosquito midgut shortly after ingestion of blood by a mosquito." In 1987, scientists declared that "This immunity could be expected to have significant effects on the natural transmission of P. vivax malaria" (Mendis).
"Development of a successful transmission-blocking vaccine is an essential step in efforts to control the global spread of malaria" (Kumar). This study indicates that "it is possible to gradually reduce malaria transmission to a point of almost eradication" (Parsons).
Sources:
Kumar, Nirbhay.
Mendis, K N. Y D Munesinghe, Y N de Silva, I Keragalla, and R Carter. Malaria transmission-blocking immunity induced by natural infections of Plasmodium vivax in humans. 1987 February.
Parsons, Tim. Vaccine Blocks Malaria Transmission in Lab Experiments. 22 July 2009.
"Researchers at the Johns Hopkins Malaria Research Institute have for the first time produced a malarial protein" that can "generate a significant immune response" and be used to create "a potential transmission-blocking vaccine" (Parsons). Antibodies produced in response to the protein, inhibit the "sexual development of the malaria-causing parasite, Plasmodium, as it grows within the mosquito".
"According to the study, a single-dose vaccine provided a 93 percent transmission-blocking immune response, reaching greater than 98 percent after a booster was given several months later" (Parsons).
Humans are on the verge of successfully creating a vaccine that may inhibit the spread of malaria. In the late 1980s, scientists understood the possibility of transmission-blocking immunity. They discovered that individuals can "develop immunity that suppresses the infectivity of the sexual stages of the parasite." This "immunity is antibody mediated and is directed against the parasites in the mosquito midgut shortly after ingestion of blood by a mosquito." In 1987, scientists declared that "This immunity could be expected to have significant effects on the natural transmission of P. vivax malaria" (Mendis).
"Development of a successful transmission-blocking vaccine is an essential step in efforts to control the global spread of malaria" (Kumar). This study indicates that "it is possible to gradually reduce malaria transmission to a point of almost eradication" (Parsons).
Sources:
Kumar, Nirbhay.
Mendis, K N. Y D Munesinghe, Y N de Silva, I Keragalla, and R Carter. Malaria transmission-blocking immunity induced by natural infections of Plasmodium vivax in humans. 1987 February.
Parsons, Tim. Vaccine Blocks Malaria Transmission in Lab Experiments. 22 July 2009.
Sunday, July 19, 2009
Malaria in China
China has seen a resurgence of Malaria in recent years. "China reported about 24 million malaria cases in the 1970s, the number of cases declined to several hundred thousand by the late 1990s. However, the disease recently has "re-emerged" in China's central and southern provinces, possibly as a result of insufficient prevention work" (Global).
China suffers from Falciparum malaria which "is the most deadly among the four main types of human malaria. Although great success has been achieved since the launch of the National Malaria Control Programme in 1955, malaria remains a serious public health problem in China" (Lin). "Falciparum malaria was endemic in two provinces of China during 2004–05" (Lin). "The 'level one' areas have an annual malaria incidence of more than one case per 10,000 people, while the 'level two' regions have an annual incidence of less than one per 10,000 people" (Global).
Map provided by Travax
"Imported malaria was reported in 26 non-endemic provinces. Annual incidence of falciparum malaria was mapped at county level in the two endemic provinces of China: Yunnan and Hainan. The sex ratio (male vs. female) for the number of cases in Yunnan was 1.6 in the children of 0–15 years and it reached 5.7 in the adults over 15 years of age" (Lin).
The recent resurgence of malaria in China has prompted "China's Ministry of Health" to draft a "plan to eliminate malaria from the country by 2015" (Xinhuanet). "Central and local governments will provide funding for the malaria control programs, an unnamed official from the health ministry's disease control department said." "The plan aims to reduce malaria incidence to less than one case per 10,000 people in high-burden regions and to no cases in low-burden regions between 2010 and 2015" (Global).
Sources:
Global Health Reporting. "Malaria | China Develops Nationwide Malaria Eradication Plan". 10 April 2009.
Lin, Hualiang. Liang Lu, Linwei Tian, Shuisen Zhou, Haixia Wu, Yan Bi, Suzanne C Ho, Qiyong Liu. Spatial and temporal distribution of falciparum malaria in China.
Xinhuanet. "China lays out plans to quell malaria" http://news.xinhuanet.com/english/2009-04/10/content_11163891.htm 10 April 2009.
China suffers from Falciparum malaria which "is the most deadly among the four main types of human malaria. Although great success has been achieved since the launch of the National Malaria Control Programme in 1955, malaria remains a serious public health problem in China" (Lin). "Falciparum malaria was endemic in two provinces of China during 2004–05" (Lin). "The 'level one' areas have an annual malaria incidence of more than one case per 10,000 people, while the 'level two' regions have an annual incidence of less than one per 10,000 people" (Global).
Map provided by Travax
"Imported malaria was reported in 26 non-endemic provinces. Annual incidence of falciparum malaria was mapped at county level in the two endemic provinces of China: Yunnan and Hainan. The sex ratio (male vs. female) for the number of cases in Yunnan was 1.6 in the children of 0–15 years and it reached 5.7 in the adults over 15 years of age" (Lin).
The recent resurgence of malaria in China has prompted "China's Ministry of Health" to draft a "plan to eliminate malaria from the country by 2015" (Xinhuanet). "Central and local governments will provide funding for the malaria control programs, an unnamed official from the health ministry's disease control department said." "The plan aims to reduce malaria incidence to less than one case per 10,000 people in high-burden regions and to no cases in low-burden regions between 2010 and 2015" (Global).
Sources:
Global Health Reporting. "Malaria | China Develops Nationwide Malaria Eradication Plan". 10 April 2009.
Lin, Hualiang. Liang Lu, Linwei Tian, Shuisen Zhou, Haixia Wu, Yan Bi, Suzanne C Ho, Qiyong Liu. Spatial and temporal distribution of falciparum malaria in China.
Xinhuanet. "China lays out plans to quell malaria" http://news.xinhuanet.com/english/2009-04/10/content_11163891.htm 10 April 2009.
Sunday, July 12, 2009
Malaria in Malawi
"Malaria is one of Malawi's most serious heath problems" (CDC). The most common malaria found in Malawi is the Plasmodium falciparum, which is "also the most lethal malaria parasite".
The entire population of Malawi is at risk for Malaria, and the highest concern is for children and pregnant women, who are victims of the most severe cases. "In 2001, malaria accounted for 22% of all hospital admissions, 26% of all outpatient visits, and 28% of all hospital deaths. Not all people go to hospitals when sick or having a baby and many die at home, and thus the true numbers are likely much higher" (CDC).
National programs have been established in Malawi to combat malaria. Malawi's National Malaria Control Programme (NMCP) and The National Malaria Technical Committee seek to reduce the cases of malaria in Malawi by using the Roll-back malaria strategy[Website: Roll Back Malaria]. First-line treatment includes the antimalarial drug, sulfadoxine-pyrimethamine, administered as both a medicine and prevention. Insecticide mosquito nets are distributed in Malawi, but their use and spread is limited due to lack of funds. Consquently, 40% of all deaths in this region are considered to be related to malaria (USAID).
The entire population of Malawi is at risk for Malaria, and the highest concern is for children and pregnant women, who are victims of the most severe cases. "In 2001, malaria accounted for 22% of all hospital admissions, 26% of all outpatient visits, and 28% of all hospital deaths. Not all people go to hospitals when sick or having a baby and many die at home, and thus the true numbers are likely much higher" (CDC).
National programs have been established in Malawi to combat malaria. Malawi's National Malaria Control Programme (NMCP) and The National Malaria Technical Committee seek to reduce the cases of malaria in Malawi by using the Roll-back malaria strategy[Website: Roll Back Malaria]. First-line treatment includes the antimalarial drug, sulfadoxine-pyrimethamine, administered as both a medicine and prevention. Insecticide mosquito nets are distributed in Malawi, but their use and spread is limited due to lack of funds. Consquently, 40% of all deaths in this region are considered to be related to malaria (USAID).
Monday, July 6, 2009
Spread of Malaria
Undoubtedly, mosquito bites are the most common way that malaria is spread. Specifically, the female anopheles mosquito is most often the culprit of infection. There are approximately sixty varieties of this mosquito.
How mosquitoes spread malaria:
When an infected individual is bitten by a mosquito, the insect ingests the gametocytes (reproductive forms of the parasite) with the blood. These gametocytes continue in the sexual phase of their cycle. Soon sporozoites (cells that infect new hosts) develop and fill the salivary glands of the mosquito. When the mosquito bites the next person, it injects the sporozoites into the human blood stream along with its saliva.
Most mosquito bites occur between 17:00 (5PM) and 07:00.
Other ways malaria is spread:
Mosquito bites are not the only way that malaria is spread. Other common methods of infection include:
Infection through Blood Transfusions:
Infection through blood transfusions is a common problem in areas where malaria is rampant. Even when an individual no longer feels sick from malaria, he/she can still transmit the disease via blood transfusion. Infectious periods differ by malaria strain, but for all strains the malaria may remain in the bloodstream for a number of years.
Infections through blood transfusions occur when the blood is not stored properly for a long enough period of time. Most infections occur when blood is stored less than five days. It is rare for blood that has been stored over two weeks to transmit the disease. Frozen plasma is not considered infectious.
Blood can be tested for the infectiousness through the indirect fluorescent antibody test or Enzyme-linked immunosorbent assay (ELISA). Visual examination of the blood manually cannot deliver conclusive results.
Another method to reduce the spread of malaria through blood transfusion is to administer chloroquine to the transfusion recipients. Chloroquine is used to prevent malaria from Plasmodium vivax, ovale and malariae.
Congenital Infection:
"80% of deaths due to malaria in Africa occur in pregnant women and children below 5 years. In Africa, perinatal mortality due to malaria is at about 1500/day" (Malaria Site). Physiological changes within the pregnant woman increases the severity of malaria symptoms. Morbidity may be caused by anemia, high fever, pulmonary edema, puerperal sepsis, and hemorrhage.
The infection may be spread from the mother to the child during pregnancy; however this occurs in less than 5% of malaria cases. Congenital malaria is most common in the first pregnancy. Generally, the placenta protects the child from the infection. However, it is possible for transmission to occur prenatally. Babies who contract the disease congenitally are born with symptoms of malaria. Also, infants born to a mother with malaria may be premature, underweight, or stillborn. Malaria and pregnancy are
Blood-instrument transmission:
Instruments that come in contact with blood (including surgical instruments and needles) may transmit the disease. Much like HIV, malaria can be spread through any contact with the blood of an infected individual. Needles (particularly those used in relation to recreational drugs) may transmit malaria if they are shared. At times, malaria was transmitted unintentionally by medical personnel seeking to inoculate against infectious diseases. Medical personal no longer uses the same needles for multiple individuals, so this risk has decreased dramatically. Intravenous drug users can still transmit the disease if needles are shared between individuals.
Note: People have been intentionally infected with malaria (via needles) as a treatment for syphilis because it produced prolonged high-fevers.
Malaria is a disease that can be treated and in some cases prevented. For information how you can help support malaria research and treatment programs, please visit: The Roll Back Malaria Partnership. Infectious bite is not currently accepting money. All donations should be directed through the individual programs.
Sources:
The Malaria Site. 6 July 2009.
Roll Back Malaria Partnership. 30 June 2009.
World Health Organization: Malaria. 26 June 2009.
Center for Disease Control: Malaria. 26 June 2009.
How mosquitoes spread malaria:
When an infected individual is bitten by a mosquito, the insect ingests the gametocytes (reproductive forms of the parasite) with the blood. These gametocytes continue in the sexual phase of their cycle. Soon sporozoites (cells that infect new hosts) develop and fill the salivary glands of the mosquito. When the mosquito bites the next person, it injects the sporozoites into the human blood stream along with its saliva.
Most mosquito bites occur between 17:00 (5PM) and 07:00.
Other ways malaria is spread:
Mosquito bites are not the only way that malaria is spread. Other common methods of infection include:
1. Blood transfusions
2. Congenital infection
3. Blood-instrument transmission
Infection through Blood Transfusions:
Infection through blood transfusions is a common problem in areas where malaria is rampant. Even when an individual no longer feels sick from malaria, he/she can still transmit the disease via blood transfusion. Infectious periods differ by malaria strain, but for all strains the malaria may remain in the bloodstream for a number of years.
The duration of time malaria remains infectious by strain:
P. falciparum: 1-3 years
P. vivax: 3-4 years
P. malariae: 15+ years (duration may be for life)
Infections through blood transfusions occur when the blood is not stored properly for a long enough period of time. Most infections occur when blood is stored less than five days. It is rare for blood that has been stored over two weeks to transmit the disease. Frozen plasma is not considered infectious.
Blood can be tested for the infectiousness through the indirect fluorescent antibody test or Enzyme-linked immunosorbent assay (ELISA). Visual examination of the blood manually cannot deliver conclusive results.
Another method to reduce the spread of malaria through blood transfusion is to administer chloroquine to the transfusion recipients. Chloroquine is used to prevent malaria from Plasmodium vivax, ovale and malariae.
Congenital Infection:
"80% of deaths due to malaria in Africa occur in pregnant women and children below 5 years. In Africa, perinatal mortality due to malaria is at about 1500/day" (Malaria Site). Physiological changes within the pregnant woman increases the severity of malaria symptoms. Morbidity may be caused by anemia, high fever, pulmonary edema, puerperal sepsis, and hemorrhage.
The infection may be spread from the mother to the child during pregnancy; however this occurs in less than 5% of malaria cases. Congenital malaria is most common in the first pregnancy. Generally, the placenta protects the child from the infection. However, it is possible for transmission to occur prenatally. Babies who contract the disease congenitally are born with symptoms of malaria. Also, infants born to a mother with malaria may be premature, underweight, or stillborn. Malaria and pregnancy are
Blood-instrument transmission:
Instruments that come in contact with blood (including surgical instruments and needles) may transmit the disease. Much like HIV, malaria can be spread through any contact with the blood of an infected individual. Needles (particularly those used in relation to recreational drugs) may transmit malaria if they are shared. At times, malaria was transmitted unintentionally by medical personnel seeking to inoculate against infectious diseases. Medical personal no longer uses the same needles for multiple individuals, so this risk has decreased dramatically. Intravenous drug users can still transmit the disease if needles are shared between individuals.
Note: People have been intentionally infected with malaria (via needles) as a treatment for syphilis because it produced prolonged high-fevers.
Malaria is a disease that can be treated and in some cases prevented. For information how you can help support malaria research and treatment programs, please visit: The Roll Back Malaria Partnership. Infectious bite is not currently accepting money. All donations should be directed through the individual programs.
Sources:
The Malaria Site. 6 July 2009.
Roll Back Malaria Partnership. 30 June 2009.
World Health Organization: Malaria. 26 June 2009.
Center for Disease Control: Malaria. 26 June 2009.
Wednesday, June 24, 2009
Advances Against Malaria | Combination Treatment
New studies conducted with children in Burkino Faso have shown that "in combination with newer malaria drugs, methylene blue prevents the malaria pathogen in infected persons from being re-ingested by mosquitoes and then transmitted to others and is thus twice as effective as the standard therapy" (University).
Methylene blue is one of the oldest synthetic treatments of malaria. In 1891, Paul Ehrlich identified its success at treating the disease (Schirmer). The chemical fell out of favor because of its cosmetic side-effects: whites of the eyes acquire a blue tint (image) and urine turns green.
Methylene blue is relatively cheap to produce and may see a resurgence in use since "combination therapies are twice as effective against gametocytes as the standard therapy" (University).
Sources:
Schirmer H, Coulibaly B, Stich A, et al. (2003). "Methylene blue as an antimalarial agent--past and future". Redox Rep 8: 272–276. doi:10.1179/135100003225002899
University Hospital Heidelberg. "Spread Of Malaria Parasites Curbed With Combination Of Methylene Blue And New Malaria Drugs." ScienceDaily 26 May 2009. 24 June 2009
Methylene blue is one of the oldest synthetic treatments of malaria. In 1891, Paul Ehrlich identified its success at treating the disease (Schirmer). The chemical fell out of favor because of its cosmetic side-effects: whites of the eyes acquire a blue tint (image) and urine turns green.
Methylene blue is relatively cheap to produce and may see a resurgence in use since "combination therapies are twice as effective against gametocytes as the standard therapy" (University).
Sources:
Schirmer H, Coulibaly B, Stich A, et al. (2003). "Methylene blue as an antimalarial agent--past and future". Redox Rep 8: 272–276. doi:10.1179/135100003225002899
University Hospital Heidelberg. "Spread Of Malaria Parasites Curbed With Combination Of Methylene Blue And New Malaria Drugs." ScienceDaily 26 May 2009. 24 June 2009
Malaria Statistics
Sobering statistics:
Sources:
Global Health Facts. "Malaria Cases". Retreived 24 June 2009.
Seattle Biomedical Research Institute (SBRI). "Diseases: Malaria". Retreatived 24 June 2009.
- 300-500 million malaria infections each year
- More than 1 million deaths each year related to malaria
- Nearly 40% of the world's population lives in affected regions.
- Malaria causes 1 in 5 of all childhood deaths in Africa
- African children have between 1.6 and 5.4 episodes of malarial fever each year.
Sources:
Global Health Facts. "Malaria Cases". Retreived 24 June 2009.
Seattle Biomedical Research Institute (SBRI). "Diseases: Malaria". Retreatived 24 June 2009.
Introduction to Malaria
Malaria is a mosquito-borne disease caused by a parasite. People with malaria often experience fever, chills, and flu-like illness. Left untreated, they may develop severe complications and die. Each year 350-500 million cases of malaria occur worldwide, and over one million people die, most of them young children in Africa south of the Sahara. (Source: Centers for Disease Control. Malaria)
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