children s health issues
Toxoplasmosis in Newborns
Introduction
Toxoplasmosis is infection with the parasiteToxoplasma gondii. It usually does not cause problems in healthy adults, but it can cause serious illness in newborns and in people with a weakened immune system. Toxoplasmosis is caused by a parasite that lives and multiplies in cats. A fetus may be born prematurely, and a newborn may have problems such as a small head or an enlarged liver. Blood tests and tests of other fluids can be done to detect the infection in the fetus, newborn, or mother. The infection may cause death in some children and long-term neurologic problems in others. Pregnant women should avoid cat litter and should thoroughly cook meat before eating it. Antiparasitic medications may be given to fetuses or newborns to treat the infection. (See also Overview of Infections in Newborns and TheToxoplasma gondiiparasite lives and multiplies mainly in cats, and its eggs are shed in cat feces. Cat feces can contaminate food, soil, and water. Pregnant women become infected if they swallowToxoplasmaeggs after they touch contaminated cat litter, soil, or other objects and then touch their mouth or handle and eat food without washing their hands. Pregnant women can also become infected if they consume raw or undercooked meat or other foods that are contaminated. Fetuses become infected ifToxoplasma gondiicrosses the placenta (the organ that provides nourishment to the fetus) during pregnancy. Women who were infected before pregnancy typically do not pass the parasite on to their fetus unless their immune system has been weakened (for example, by HIV infection), reactivating the infection. Infection in the fetus is more severe if the fetus is infected earlier in pregnancy. 1a. Eggs are passed in cat stool. Many eggs are passed but usually for only 1 to 2 weeks. After 1 to 5 days in the environment, eggs become able to cause infection. 1b. Cats can become reinfected by consuming food or other materials contaminated with the eggs. 2. Other animals (such as wild birds, rodents, deer, pigs, and sheep) may consume the eggs in contaminated soil, water, plant material, or cat litter. 3. Shortly after the eggs are consumed, they release forms of the parasite that can move (called tachyzoites). 4. Tachyzoites spread throughout the animal's body and form cysts in nerve and muscle tissue. 5. Cats become infected after eating animals that contain these cysts. 6a. People can become infected by eating undercooked meat containing these cysts. 6b. People can also become infected if they eat food, water, or other materials (such as soil) contaminated with cat stool or when they touch a pet cat's litter and then touch their mouth. 7. Rarely, people are infected when they have a blood transfusion or organ transplant that contains the parasite. 8. Rarely, the infection is spread from mother to fetus. 9. In people, parasites form cysts in tissues, usually in muscle and the heart, brain, and eyes. 