The effects of parasite strain variety on the development and severity of Chagas disease may be clarified by recent Tulane University research.
Trypanosoma cruzi parasites, which are spread by kissing bugs and are the cause of the lesser-known and studied tropical disease chagas, are found in those insects. The disease affects 6 million individuals in 21 countries around the Americas, and 30,000 new cases are reported yearly.
Approximately 20–40% of infected individuals will acquire chronic heart disease years or decades after infection, while only approximately 5% will develop a digestive ailment, even though the majority of infected patients remain asymptomatic. Chagas disease has an uncertain course and 14,000 people die from it every year, making treatment difficult.
In a new study published in Microbiology Spectrum, Tulane researchers were able to establish a link between disease progression and parasite strain diversity.
Since the 1980s, researchers have proposed that different strains could be associated with different disease outcomes due to the parasite’s genetic diversity, but decades of research failed to uncover clear associations. In finding a clear association, these results provide a new framework for the development of more effective treatments and vaccines.
Professor Eric Dumonteil
Two to three years of research on Rhesus macaques naturally infected with T. cruzi revealed that while those with a progressive form of the disease had fewer strains, those with mixtures of multiple strains were better able to control the parasite and stop the progression of the disease.
“Since the 1980s, researchers have proposed that different strains could be associated with different disease outcomes due to the parasite’s genetic diversity, but decades of research failed to uncover clear associations,” said lead study author Eric Dumonteil, PhD, associate professor of tropical medicine at Tulane University School of Public Health and Tropical Medicine. “In finding a clear association, these results provide a new framework for the development of more effective treatments and vaccines.”
Dumonteil said studies are ongoing to further understand the interactions of various parasite strains during infection.
The study was co-authored by Dumonteil, Hans Desale, PhD, Claudia Herrera, PhDand Preston Marx, PhD, from the Department of Tropical Medicine. The research was conducted at the Tulane National Primate Research Center.
Medical research specialist Kelly Goff, Monica Shroyer and Weihong Tu. Nora Hernandez-Cuevas from the Autonomous University of Yucatan in Mexico collaborated in the study provided technical support.
