Toxoplasmosis is caused by a microscopic parasite called Toxoplasma gondii, which lives in animal tissues. The cat is the primary host. Toxoplasma is widespread in nature and can infect birds and a variety of mammals, including people.
Cats contract toxoplasmosis by eating infected raw meat, infective Toxoplasma cysts in feces, or contaminated water. Infected cats may or may not show illness. Signs include diarrhea, fever, labored breathing, enlarged lymph nodes, eye inflammation, and occasionally death. Cats usually develop immunity to toxoplasmosis after the initial infection and never pass the organism again.
Other animals and people become infected by eating the incubated cysts or uncooked meat containing Toxoplasma cysts. Toxoplasma may invade and form cysts in such organs as the brain, heart, and skeletal muscle.
Public Health Significance
A woman who plans to have a child can be tested for antibodies to Toxoplasma before becoming pregnant. If she has antibodies, then she and her unborn child will not be infected. If she has no antibodies, she could transmit the organism to her unborn child if she became infected during pregnancy. You should discuss the blood test for Toxoplasma antibodies with your physician before becoming pregnant.
Cat Management in a Household with an Expectant Mother
1. Your cat’s blood should be tested for antibodies. Two tests, 2 to 3 weeks apart, are recommended. If infected, your cat can be treated for toxoplasmosis.
2. Your cat’s stool should be checked for parasite eggs or cysts. The expectant mother should not handle the stool sample.
3. Pregnant women should not clean the litter box. The litter box should be emptied daily.
4. Children’s sand boxes should be covered when not in use.
5. Cats should not be allowed to catch rodents or birds or to eat raw meat.
6. Do not allow stray cats into the household.
7. Wash your hands after petting or handling the cat.
Pregnancy does not mean that you cannot own a cat, but common sense should prevail. Eating raw or undercooked meat is probably a much more important source of human toxoplasmosis than contracting the disease from cats. Heating meat to at least 150° F kills Toxoplasma.