- When an uninfected host consumes a tissue cyst, bradyzoites released from the cyst infect intestinal epithelial cells before converting to the proliferative tachyzoite stage.
- When a human or other warm-blooded host consumes an oocyst, sporozoites are released from it, infecting epithelial cells before converting to the proliferative tachyzoite stage.
- "T . gondii " is considered to have three stages of infection; the tachyzoite stage of rapid division, the bradyzoite stage of slow division within tissue cysts, and the oocyst environmental stage.
- Following the initial period of infection characterized by tachyzoite proliferation throughout the body, pressure from the host's immune system causes " T . gondii " tachyzoites to convert into bradyzoites, the semidividing cellular stage of the parasite.