NTDs and the skewed burden of disease

July / August 2011 | Volume 10, Issue 4

Woman researcher closely observes samples in dish, many vials of liquid in foreground
Photo courtesy of NIAID

NIAID researchers study cells infected with
the dengue virus.

Though of low prevalence in most of the United States, tropical diseases such as dengue fever, lymphatic filariasis, leishmaniasis and schistosomiasis take a tremendous toll on global health. According to recent estimates, more than one billion people - about one-sixth of the world's population - suffer from at least one neglected tropical disease (NTD). These diseases tend to thrive among impoverished populations in developing regions of the world, where water quality, sanitation and access to health care are substandard.

The National Institute of Allergy and Infectious Diseases (NIAID) supports a robust program of research devoted to better understanding, preventing and treating NTDs. Studies conducted and supported by NIAID have led to important new discoveries about the microbes that cause these diseases, the identification of targets for potential new drugs and vaccines, and the development of strategies for controlling the vectors that transmit NTD-causing agents to humans.

For example, NIAID-supported investigators have sequenced the genomes of Trypanosoma brucei, Trypanosoma cruzi, and Leishmania major, the parasites that cause the diseases African sleeping sickness, Chagas' disease, and leishmaniasis, respectively. Researchers also have sequenced the genome of Aedes aegypti, the mosquito species that transmits dengue and yellow fever. Currently, NIAID investigators are working on sequencing the genomes of two other important NTD vectors: the tsetse fly, which transmits T. brucei to humans, and the freshwater snail Biomphalaria glabrata, which transmits a parasite that causes schistosomiasis. This new genetic information promises to help researchers design better ways to diagnose, treat and prevent NTDs.

Through its Partnerships with Public-Private Partnerships program and Tropical Disease Research Units, NIAID is actively supporting the discovery and development of treatments for parasitic tropical diseases. For example, researchers in these programs are developing a low-cost treatment for visceral leishmaniasis, the most severe form of the disease, and identifying new drugs for African sleeping sickness and Chagas' disease.

Recently, scientists supported in part by NIAID identified cellular components in mosquitoes and in humans that dengue viruses use to multiply inside both hosts. Their findings could lead to the development of drugs that would inhibit one or more of these components, thus limiting infection and the development of dengue fever. The search for anti-dengue therapies is vital, as no specific drugs or vaccines are available to fight dengue infection, which afflicts up to 50 million people worldwide each year.


This article was adapted from NIAID Global Research: Improving Health in a Changing World [PDF 7M, 24 pages].

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