When humans have parasites, the organisms live in our bodies, co-opt our resources and cause disease. However, it turns out that parasites themselves can have their own co-habitants.
Researchers from Harvard Medical School, Brigham and Women's Hospital and SUNY Upstate Medical University have found that the pathogenicity of the sexually transmitted protozoan parasite Trichomonas vaginalisthe cause of trichomoniasisis fueled by a viral invader. Trichomoniasis infections are more common than all bacterial STDs combined. Annually, trichomoniasis affects nearly 250 million people, typically as vaginitis in women and urethritis in men.
"Trichomoniasis is associated with devastating consequences for women due to inflammation and related risks of reproductive disease," said Raina Fichorova, leader of the research team as well as associate professor of obstetrics, gynecology and reproductive biology at Brigham and Women's Hospital. "Our future goal is to determine how the viral symbiont and its inflammatory 'halo' affect the risk of preterm delivery and low birth weight."
"This is only one of two incidences that we know of for which the pathogenicity of a protozoan virus has been characterized," said Max Nibert, Harvard Medical School professor of microbiology and immunology and co-author of the paper. "When found together, the result is an increase in virulence of the protozoan parasite to the human host, leading to exacerbated disease."
This study, which was initiated by a Harvard Catalyst Pilot grant, will be published online in Public Library of Science (PLOS) One.
Rather than invading human cells, Trichomonas vaginalis attaches to their surface and feeds on them, sometimes remaining asymptomatic for a period of time. The virus, called Trichomonasvirus, infects the protozoan and increases its pathogenic power by fueling virus-specific inflammatory responses.
Moreover, carrying the protozoan pa
|Contact: David Cameron|
Harvard Medical School