Toxoplasmosis

Routine examination of the retina can often reveal old lesions of toxoplasmosis. (retinitis caused by an obligate intracellular protozoan). Humans can become infected in one of the following ways.

1. Ingestion of undercooked meat. (lamb, pork, beef)

2. Ingestion of the oocyst following accidental contamination of hands when disposing of cat litter trays and then subsequent transfer on to food. Infants may also become infected by eating dirt containing oocysts.

3. Transplacental spread of the parasites can occur to the fetus in a pregnant woman with acute toxoplasmosis.

Reference: Kanski, Jack J., Clinical Ophthalmology (page 175)