Freedom from Malaria for All
By Alexandra Reihing | July 11, 2007
Nearly one million people die from malaria each year. Most are African children. While malaria has been eradicated in the United States, Europe, and parts of Latin America with the help of indoor residual spraying of DDT, it remains the largest killer of children under the age of five in sub-Saharan Africa. Those who are spared death may fight other battles with the disease—contracting malaria once does not guarantee future immunity. Because of the damaging effects malaria has on the infected and their families, Robert Gwadz of the National Institutes of Health suggests, "It's possible that due to malaria almost every child in Africa is in some way neurologically scarred."
Malaria is an infection of the red blood cells caused by a parasite that is carried in the saliva of certain female Anopheles mosquitoes. Four protozoan species of the Plasmodium genus are primarily responsible, each with its own epidemiology and hence its own treatment.
The symptoms manifest in two forms. Uncomplicated malaria entails headache, fatigue, and abdominal, muscle, and joint pain, followed by fever, chills, perspiration, and vomiting. Severe malaria occurs either when ineffective drugs have been administered or no drugs are available and the parasite content in the blood grows very quickly. Severe malaria may bring on coma, seizures, kidney failure, respiratory failure, and brain damage. Without drugs, severe malaria is always fatal. With drugs, the survival rate jumps to 80–85 percent.
350–500 million people get sick with malaria each year. Malaria is a huge drain on sub-Saharan Africa's economic and social growth, as it hampers employment, investment, human development, and family dynamics.
Transmission of the disease depends on previous exposure and how often a person gets bitten. Transmission is stable in areas where the population is continuously exposed to a constant rate of malarial inoculations. In this case, partial immunity develops. Such is the situation in most of sub-Saharan Africa, which explains why adolescents and adults are largely safe from the disease while children are not. Transmission is unstable in areas where inoculation rates vary widely over the seasons and years. In this case, immunity is slowed and the disease affects people of all ages. Such is the situation in Asia and Latin America.
Eradication of malaria became a central goal of the World Health Organization (WHO) after malarial casualties were sustained in World War II. In 1957, the WHO launched a ten-year eradication program based on the spraying of DDT in indoor areas. Mosquitoes die after landing on sprayed walls. In all, 24 countries were declared malaria-free by the time the program ended in 1969.
Yet infections remained consistently high in sub-Saharan Africa for several reasons. Many countries where malaria was endemic were not included in the program. There was also a general lack of scientific knowledge about the factors that were influencing the high rates of transmission in the tropics. The notion that solving the problem was impossible became common, and after 1969 funding was directed toward other issues.
DDT has a checkered past. Its insecticidal properties were discovered by Swiss chemist Paul Müller in 1939. Released in microscopic amounts, DDT can kill mosquitoes for months at a time, twice as long as the next best insecticide. It is also cheap, costing one-quarter as much as other remedies. Its identification as an environmental toxin did not occur until 1962, the year Silent Spring by Rachel Carson was published and the American public became familiar with the downsides of DDT. When used in large amounts in open areas, such as farming, DDT sinks into groundwater and has harmful effects on animals, particularly fish and birds.
DDT was banned in the United States in 1972, though the Stockholm Convention governing persistent organic pollutants allows for its continued use for public health purposes. Small amounts of DDT may be used for indoor spraying in tropical areas where malaria transmission is high.
The WHO and G8 governments have long held to the belief that African infrastructure is too poor to support wide-scale DDT spraying. The lobbying of environmentalists who echo Rachel Carson's concerns has also restricted DDT use in Africa. According to Gwadz, "The ban on DDT may have killed 20 million children."
Sam Zaramba, general director of health services in Uganda, has argued, "Environmental leaders must join the 21st century, acknowledge the mistakes Carson made, and balance the hypothetical risks of DDT with the real and devastating consequences of malaria." The bottom line—DDT works. Uganda's use of DDT, supported by President Bush's Malaria Initiative, in August 2006 and February 2007 resulted in the spraying of 100,000 households. The rate of infection in the covered area dropped to just 3 percent, down from 30 percent.
After DDT, the next best preventer of infection is insecticide-treated bed nets, and there is currently a push to get these distributed throughout sub-Saharan Africa. Over the next five years, The Global Fund to Fight AIDS, Tuberculosis, and Malaria (GATM) will finance the distribution of 120 million insecticide-treated bed nets. It is Jeffrey Sach's dream that all Africans will be protected from malaria with bed nets. Sachs, director of the Earth Institute and special advisor to the Secretary-General of the UN, is currently carrying out his Millennium Villages Project in 79 villages in ten African countries. As part of the Project's wider aim of poverty eradication, bed nets are distributed to villagers to reduce malaria contraction and transmission. The incidence of malaria in Sach's first village, Sauri, Kenya, has fallen by two-thirds in the three years since the program began.
Sachs argues that solving the malaria problem is not as complicated as it is made out to be: "The more I study controlling malaria… the more straightforward it all is. Ignorance breeds fear that these problems are too big to tackle." He maintains that malaria is controllable in Africa, if only enough money is spent. Sub-Saharan Africa spends an average of only $20 per person per year on health care. In one village Sachs visited, only $1.90 was allocated for health care per person. The United States spends $6,000 per person per year on health care. Sachs makes a good case for the fact that the industrial world, and especially the United States, can afford to give much more to African health care than it currently does.
The UN Millennium Project's Working Group on Malaria found that it would take $2–3 billion each year for three years to assist African governments to control malaria transmission. The aid would go toward the distribution of free bed nets and increased access to drugs.
The third element of malaria control is drug treatment. There are a number of drug options for the treatment of malaria, all of which aim to prevent transmission. The most-used is chloroquine, though malarial strains have adapted and developed resistance to this and other antimalarial drugs. "In its ability to adapt and survive, the malaria parasite is a genius. It's smarter than we are," says Gwadz.
The prevention of resistance has therefore become a major aim of treatment. Artemisinin-based combination therapies, or ACTs, in which a cocktail of drugs are administered, are now acknowledged as the best treatment option for uncomplicated malaria. The idea is that if the organism develops resistance to one of the drugs in the cocktail, the other one can still work to knock out the infection. The Global Fund will provide 264 million artemisinin-based combination therapy treatments for resistant malaria over the next five years.
What is really needed is a vaccine, which is easier said than done: Because malaria has four strains, producing a vaccine effective against all of them is very difficult. Stephen Hoffman is the founder and CEO Sanaria (or "healthy air," the opposite of malaria), and is attempting to develop a vaccine for the most resistant strain. The idea is to create a vaccine made up of parasites extracted from the saliva of mosquitoes treated with radiation.
Defeating malaria in Africa would lessen security fears on the continent and promote economic investment and growth, with profound benefits for human development. As part of the Millennium Development Goals, UN members have committed to halting and reversing malaria by 2015. A large amount of aid is required to accomplish this goal. At the G8 Summit, the group reaffirmed its previous commitment to this goal by improving health systems and fighting malaria in Africa, where 90 percent of malaria deaths occur, with at least $60 billion in the coming years.
The Global Fund has thus far disbursed more than $4 billion for malaria control and treatment. The G8 pledged to replenish the Fund, which estimates it will require an additional $6–8 billion in support by 2010. Freedom from malaria should not be denied to sub-Saharan Africa when it is possible to achieve. Indoor DDT spraying, bed nets, and ACTs have demonstrated that infection and transmission rates, along with resistance, can be lowered significantly.blog comments powered by Disqus