June 1, 2006 — An infectious disease research team at the University of Virginia Health System has been awarded a $4.2 million, 5-year grant from the National Institutes of Health to develop a vaccine against a worldwide killer — the disease amebiasis. About 50 million people each year suffer from invasive amebic infection, and about 40,000 to 100,000 die annually from its effects. The gut-dwelling parasite Entamoeba histolytica wreaks havoc on digestive systems of children and adults, causing diarrhea and dysentery.
“There is a substantial burden of infection due to this protozoan parasite,” said William Petri, chair of the UVa Division of Infectious Diseases and International Health. “We are pleased to receive word of this grant and we’re eager to start working on the vaccine.”
The research team, led by Dr. Petri, will work to produce a vaccine against Entamoeba histolytica and test the vaccine’s effectiveness. The target for the vaccine is a protein called the Gal/GalNAc lectin. This lectin is a target because it allows the parasite to adhere to gut tissue more easily and kill healthy cells.
The research team comprises William A. Petri Jr., M.D., Ph.D., Eric Houpt, M.D., Shinjiro Hamano, Ph.D., Girija Ramakrishnan, Ph.D., all from the Division of Infectious Diseases and International Health, and David Lyerly from TechLab Inc., which develops and manufactures intestinal diagnostic products.
A U.Va. Infectious Disease Division prospective study of preschool children in a slum of Dhaka Bangladesh demonstrated new E. histolytica infection in 39 percent of children during a one-year observation period, with 10 percent of the children having an E. histolytica infection associated with diarrhea and 3 percent with dysentery. Carefully conducted serologic studies in Mexico, where amebiasis is common, demonstrated antibody to E. histolytica in 8.4 percent of the population. New epidemiologic studies are making a humanitarian case for creating this product for use in the developing world where the infection lingers.