Those who live in tropical areas around the world are at risk for malaria. In fact, malaria is a top cause of infant mortality in some countries. Numerous advances have been made to curb the instances of malaria, and medical devices have also been developed to detect malaria in underdeveloped countries. However, a new study at the Bloomberg School of Public Health suggests a far simpler solution. The researchers propose that a timely increase in vitamin A intake may decrease the chances of being infected.
Malaria is caused by parasitic protozoans that travel from host to host through mosquitoes. There are several strains of malaria, out of which P. falciparum is the deadliest. These microorganisms most commonly reside in the Anopheles mosquito and are transmitted through their bites.
Once the mosquito bites a host, the parasite travels from the mosquito saliva into the bloodstream. The protozoans then mature in the liver and begin to reproduce. After two weeks, symptoms of malaria appear, including fever, vomiting and fatigue. More severe cases may result in seizures, coma or death. Without adequate treatment, malaria patients may have recurring symptoms for months. However, patients who recover from infection may retain partial immunity for months or years.
Though malaria affects hundreds of thousands every year, scientists found that vitamin A supplements significantly protect people against malaria. By sifting through national surveys of sub-Saharan nations, they found correlations between vitamin A supplements and rates of malaria infection. In some countries, children younger than five years old who received vitamin A supplements decreased their chances of infection by 54 percent.
Furthermore, the timing of receiving the supplements appears to contribute to the protection. The supplements have the greatest impact when administered during the wet season and when some time has passed since the last dosage. Older children also develop better protection with the supplements.
Despite the improved malaria protection from vitamin A supplements, more than 80 percent of malaria incidents still occur in these countries and seven percent of infant deaths are caused by malaria. In fact, out of the national surveys, only 62 percent of children took vitamin A. This rate is lower than many vaccination programs active in these countries. The World Health Organization guidelines for vitamin A supplements are less strict than some vaccination programs, contributing to lower instances of administration.
While these findings are intriguing, scientists still do not understand the role of vitamin A in malaria prevention. Vitamin A seems to play an important role in the immune system. Patients who are vitamin A deficient also suffer from immunodeficiency, meaning that their immune systems don’t function as well as they should. On the other hand, subjects who have adequate amounts of vitamin A show improved lymphocyte proliferation when confronted with antigens. Lymphocytes are important killer cells that help rid the body of foreign objects, highlighting a potential link between vitamin A and immunity. Though there are theories surrounding the effects of vitamin A in the immune system, further studies need to be conducted to substantiate these theories.
Malaria threatens much of the world’s population, causing thousands of deaths and infecting hundreds of thousands each year. The disease has proven hard to eradicate, but the new studies suggest a simple way of offering additional protection against the disease.
Though new vaccines are constantly being developed, the best vaccine under development is only 50 percent effective. As a result, countries may have to rely on vitamin A supplements to safeguard their citizens against this tropical disease before a vaccine is developed.