Biologists find clues to a parasite’s inconsistency
Toxoplasma gondii, a parasite related to the one that causes malaria, infects about 30 percent of the world’s population. Most of those people don’t even know they are infected, but a small percentage develop encephalitis or ocular toxoplasmosis, which can lead to blindness. MIT biologist Jeroen Saeij and his colleagues are trying to figure out why some forms of the disease are so innocuous, while others ravage their victims. In their latest paper, they analyzed 29 strains of the parasite and found that some of those endemic to South America or atypical in North America provoke very strong inflammation in the cells they infect, which can severely damage tissue.“You have a lot of strains that are silent, and then you have these exotic strains that can cause very severe disease,” says Saeij, the Robert A. Swanson Career Development Associate Professor of Life Sciences. “The goal of the project was to...