The Pathogen
Toxoplasma
gondii, a coccidian in the phylum Apicomplexa, is an obligate
intracellular parasite of global distribution, with seroprevalences
reaching above 80% in some populations. Despite this high prevalence, serious
complications from toxoplasmosis are rare in immuno-competent hosts and are largely
limited to patients with suppressed or underdeveloped immune systems,
such as AIDS patients, organ-transplant recipients, and neonates.Toxoplasma also serves as a model organism for studying the invasion of other apicomplexan pathogens of medical and veterinary importance including the agents of Malaria and Cryptosporidiosis.
Scanning EM of Toxoplasma invading a Fibroblast cell