Ocular toxoplasmosis is an infection in the eye caused by the parasite, Toxoplasm a gondii. Toxoplasmosis is the most common cause of eye inflammation in the world. Toxoplamosis can be acquired or present at birth (congenital), having crossed the placenta from a newly infected mother to her fetus. Most humans acquire toxoplasmosis by eating raw or undercooked meat, vegetables or milk products, or by coming into contact with infected cat litterbox or sandboxes. In individuals with compromised immune systems, Toxoplasm a gondii can reactivate to cause disease. Reactivation of a congenital infection was traditionally thought to be the most common cause of Ocular toxoplasmosis, but an acquired infection is now considered to be more common. A toxoplasmosis infection that affects the eye usually attacks the retina and initially resolves without symptoms. However, the inactive parasite may later reactivate causing eye pain, blurred vision, and possibly permanent damage, including blindness.