Malaria is a difficult disease to control largely due to the highly adaptable nature of the vector and parasites involved. While effective tools have been and will continue to be developed to combat malaria, inevitably, over time the parasites and mosquitoes will evolve means to circumvent those tools if used in isolation or used ineffectively. To achieve sustainable control over malaria, healthcare professionals will need a combination of new approaches and tools, and research will play a critical role in development of those next-generation strategies.
Malaria has a significant impact on the health of infants, young children, and pregnant women worldwide. More than 800,000 African children under the age of five die of malaria each year. Malaria also contributes to malnutrition in children, which indirectly causes the death of half of all children under the age of five throughout the world. Fifty million pregnant women throughout the world are exposed to malaria each year. In malaria-endemic regions, one-fourth of all cases of severe maternal anemia and 20 percent of all low-birthweight babies are linked to malaria. Scientists are working to better understand how malaria uniquely affects children and pregnant women and to develop new research tools, methods, and products appropriate for these populations.
The development of a safe and effective vaccine against malaria will be critical in malaria control, prevention, and eradication efforts. Currently, no licensed vaccine against malaria (or any parasitic disease that afflicts humans) exists. The complexity of the Plasmodium parasite and the lack of understanding of critical processes, such as host immune protection and disease pathogenesis, have hampered vaccine development efforts.
NIAID supports a broad research program to encourage vaccine development. Several candidate vaccines that target various life cycle stages of the malaria parasite are in development. In addition, NIAID is exploring novel vaccine strategies, such as transmission-blocking vaccines, which work by blocking transmission of the malaria parasite to the mosquito vector.
Antimalarial drugs, in combination with mosquito control programs, have historically played a key role in controlling malaria in endemic areas, resulting in significant reduction of the geographic range of malarial disease worldwide. Over the years, however, the emergence and spread of drug-resistant parasites has contributed to a reemergence of malaria, turning back the clock on control efforts. The need for new, effective drugs for malaria has become a critical priority on the global malaria research agenda.
NIAID-supported researchers are seeking to understand the molecular biology of the Plasmodium parasite and how it interacts with its human host at each stage in that cycle. Using that information, scientists hope to develop new drugs that block different molecular processes required for parasite survival and identify the mechanisms of emerging drug resistance.
New and improved diagnostics are essential for the effective control of malaria. Currently, the most reliable technique for diagnosing malaria is, as it was throughout the last century, labor-intensive, relying on highly trained technicians using microscopes to analyze blood smears. Such microscopic analysis is time-consuming, variable in quality, difficult to use in resource-poor field settings, and cannot detect drug resistance. Therefore, NIAID supports research to develop easy-to-use tests that diagnose the malaria parasite causing an infection and identify its drug resistance profile.
Vector Management Approaches
Vector management tools such as insecticides, environmental modification, and bed nets have contributed greatly to successful malaria control efforts historically, but have faced setbacks in recent years due to factors such as the emergence of insecticide resistance in mosquitoes. NIAID is supporting research on new vector management strategies to prevent parasite transmission (from humans to mosquitoes and mosquitoes to humans) and reduce the mosquito population.