Toxoplasmosis is an infection caused by the parasite Toxoplasma gondii. Infection occurs when tissue cysts in raw or undercooked meat from an infected animal are eaten. Infection can also occur by ingestion of food or water contaminated with Toxoplasma eggs from feces of infected animals. Another, less common method of infection is eating eggs that are from dirt in sandboxes or yards in which cats have defecated. If a pregnant woman becomes infected, the parasite can be transmitted to her developing fetus and cause severe illness.
Members of the cat family are infected by eating cysts of Toxoplasma parasites present in the flesh of infected animals. Cats can also become infected by ingesting Toxoplasma eggs from contaminated food or water. The parasite completes its life cycle in the cat, which produces millions of Toxoplasma eggs in its stool. Once outside the cat, the eggs mature and become infectious for people and other animals.
People who are exposed to the parasite include gardeners, veterinarians, butchers, meat cutters, and cat owners. Persons eating raw or undercooked meat are also at risk. Healthy adults generally have few or no signs of infection. Persons with weakened immune systems can develop symptoms about 5 to 20 days after infection. These include muscle aches, fever, breathing difficulty, and signs of inflammation of the brain. If a woman is infected shortly before or during pregnancy, the infection may be passed to the developing fetus. The baby may be born with mental retardation, blindness, or epilepsy.
Infection can be prevented by:
Cooking meat to a safe temperature.
Peeling or thoroughly washing fruits and vegetables before eating.
Wearing gloves when you garden or do anything outdoors that involves handling soil; cats, who may pass the parasite in their feces, often use gardens and sandboxes as litter boxes.
Washing your hands well with soap and warm water after outdoor activities, especially before you eat or prepare any food.
Pregnant women or immunocompromised individuals avoiding changing cat litter or, if no one else is available to change the cat litter, clean the litter daily using gloves, then wash hands thoroughly.
Not feeding raw or undercooked meat to cats and keeping cats inside to prevent acquisition of Toxoplasma by eating infected prey.