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Q: I am pregnant and I have heard that my cat may have a disease called toxoplasmosis that can harm my unborn child.

A: Toxoplasmosis is a disease caused by a parasite called Toxoplasma gondii. If a pregnant woman becomes infected with the Toxoplasma parasite, her baby may be born with serious abnormalities including blindness and mental retardation. There are many ways a woman can get toxoplasmosis while pregnant -- improper care of cats is just one of them. The Toxoplasma parasite infects essentially all cats that spend time outdoors. Cats get the infection by eating raw meat or small animals that carry the parasite. The parasite is then passed in the cat feces. Since the cat is rarely ill from the infection, it is unlikely that you will know when the cat is infectious. The cat is infectious for only a short period of time -- usually two weeks. After the cat passes the parasite it takes more than one day to become infectious to humans. Follow these important tips:

If possible, have someone else change the litter box.

If you must change the litter box while pregnant, wear disposable gloves and wash your hands with soap.

Wear gloves while gardening or handling sand from a sandbox. Wash your hands with soap and water after these activities.

Feed cats commercial dry foods. Never feed a cat raw meat.

Keep indoor cats indoors.

Avoid stray cats -- particularly kittens.

Do not get a new cat during pregnancy.

Eating raw or undercooked meat and unwashed fruits and vegetables are other ways of becoming infected by Toxoplasma.

-- Daniel Lattanzi, M.D.
Obstetrics and Gynecology