(Lansing State Journal, April 16, 1997)
Have you ever read a kitty litter bag? If you have, you probably have come across an unexpected warning: "People with immune deficiency and pregnant women should be advised that cat feces may carry a parasite which causes toxoplasmosis. Take care to wash your hands after contacting used kitty litter."
The parasite referred to in this warning is Toxoplasma gondii, a single-celled organism that invades the intestinal tracts of cats. Toxoplasma also can infect dogs, pigs, chickens and variety of other warm-blooded animals, but it is only within cats that it can form infectious offspring that are released in the feces. In other animals, toxoplasma may get into muscles and other tissue to form a resting stage that can persist for their entire lives.
People contract toxoplasma from the feces of infected cats or by eating uncooked meat from infected animals (pigs and sheep are a common source)
About 50 percent of adults in the United States have been infected with toxoplasma at some time, though most show no symptoms. Our immune systems typically protect us from harm caused by toxoplasma, but this is not the case for a developing fetus. If a woman contracts toxoplasma while pregnant, the parasite can reach her developing baby. The baby's immune system is not able to defend against the parasite, and damage to the eyes, brain or even a miscarriage may occur.
Preventive measures will reduce the risk of toxoplasma infection. These include keeping your cats indoors and not feeding them raw meat as well as washing with soap after handling raw meat, working in the garden or cleaning the litter box.