Background on Malaria

Mosquito

Malaria is one of the most severe public health problems worldwide. It is a leading cause of death and disease in many developing countries, where young children and pregnant women are the groups most affected.

According to the World Health Organization’s World Malaria Report 2010:

  • At the end of 2009, more than half the worldwide population lived in areas at risk of malaria transmission in 107 countries and territories.
  • The number of worldwide malaria cases hit 225 million in 2009.
  • At least 781,000 died in 2009 due to malaria.
  • About 60% of the cases of malaria worldwide and more than 80% of the malaria deaths worldwide occur in Africa south of the Sahara.

Because of the severity of the health disease, malaria was included in the Millennium Development Goals which were established by the United Nations in 2000 with the intention of tackling global poverty and health inequality. Goal 6 included the target to "halt and begin to reverse the incidence of malaria and other major diseases". Unfortunately, a report published in July 2008 in PLos Medicine states that this goal is unlikely to be met.

According to research conducted as part of the Malaria Atlas Project, over 40% of the world's population is at risk from infection from the parasite which causes malaria. Wellcome Trust Principal Research Fellow Professor Bob Snow and colleagues from the University of Oxford, who worked on the research jointly, have identified the areas where risk is moderate or high and areas where the risk is relatively low and compared this to levels of funding to control malaria in these areas. They also analyzed where funding was allocated for malaria control from major donors such as the Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM), the World Bank and the US President's Initiative, and from national governments.

In 2010, annual funding for malaria control, which includes insecticide-spraying, use of insecticide-treated bed nets and access to rapid diagnosis and medicine, amounted to US$1.8 billion – less than US$1 per person at risk. Previous studies have estimated the optimum amount required to tackle malaria to be between US$4-5.

The researchers found a wide range of regional disparity between risk levels and amount of money allocated to the area for malaria control. For example, Burma (Myanmar) received US$0.01 for each person at risk, compared to US$147 in Suriname, South America. Certain areas, such as Africa, the Americas and the Middle East, received appropriate levels of the funding disbursed, but there were large shortfalls in other regions, such as South East Asia and the Western Pacific regions.

"There is clearly a lot of good will from the international community to tackle malaria, but more money needs to be invested and this needs to be distributed more equitably," says Professor Snow, who is based at the Kenya Medical Research Institute (KEMRI) in Nairobi, Kenya. "If not, it is unlikely that the Millennium Development Goal to tackle malaria will be met.

"We need to map where the problems are and where investment is most needed if we are to target the funds more effectively. This has been one of the primary intentions of the Wellcome Trust-funded Malaria Atlas Project. Without a map we could easily be missing the target and wandering around in endless circles."

The Disease

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 sub-Saharan Africa.

This sometimes fatal disease can be prevented and cured. Bed nets, insecticides, and anti-malarial drugs are effective tools to fight malaria in areas where it is transmitted. Travelers to a malaria-risk area should avoid mosquito bites and take a preventive anti-malarial drug.

Malaria can affect a person's health in various ways.

  • People who have developed protective immunity (through past infections, as is the case with most adults in high transmission areas) may be infected but not made ill by the parasites they carry.
  • In most cases, malaria causes fever, chills, headache, muscle ache, vomiting, malaise and other flu-like symptoms, which can be very incapacitating.
  • Some persons infected with a particularly virulent strand (Plasmodium falciparum) can develop complications such as brain disease (cerebral malaria), severe anemia, and kidney failure. These severe forms occur more frequently in people with little protective immunity, and can result in death or life-long neurologic impairment.
  • People subjected to frequent malaria infections (such as young children and pregnant women in high transmission areas) can develop anemia due to frequent destruction of the red blood cells by the malaria parasites. Severely anemic patients might receive blood transfusions which, in developing countries, can expose them to HIV and other blood-borne diseases.
  • Babies born to women who had malaria during their pregnancy are more often born with a low birth weight or prematurely, which decreases their chances of survival during early life.
  • In developing countries, the harmful effects of malaria may combine with those of other highly prevalent diseases and conditions, such as malnutrition, HIV/AIDS, and anemia of all causes. Such combinations can have severe results, especially if they occur repeatedly.

Who Is Most Vulnerable

Persons most vulnerable are those with no or little protective immunity against the disease. In areas with high transmission (such as Africa south of the Sahara), the most vulnerable groups are:

  • Young children, who have not yet developed immunity to malaria
  • Pregnant women, whose immunity is decreased by pregnancy, especially during the first and second pregnancies
  • Travelers or migrants coming from areas with little or no malaria transmission, who lack immunity.

In areas with lower transmission (such as Latin America and Asia), residents are less frequently infected. Many persons may reach adult age without having built protective immunity and are thus susceptible to the disease.

Sources:

World Health Organization

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