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Ocular toxoplasmosis

Toxoplasma is a parasitic infection humans may contract from cats, undercooked meat or poultry, or poorly sanitized water. The mode of transmission from cats may be indirect: a child may play in a sandbox contaminated with cat feces, a pregnant mother may clean out a kitty litter box, or a family dog may roll around in soil or sand contaminated with cat droppings and then bring the parasite into the house.

Toxoplasma may exist in an "active form" and in a "cyst form." Antibiotics may kill the active form but do not always kill the cysts. If a human is infected, the cyst form may persist in the retina within a small retinal scar and cause occasional episodes of inflammation inside the eye (retinochoroiditis), which must be recognized and treated appropriately. Toxoplasma retinochoroiditis can be vision threatening.

Medline Plus article on Toxoplasmosis

Ophthalmology Times article on toxoplasmosis

European uveitis patient group: article on ocular toxoplasmosis (caution: this file is large and may take time to download).