by Amanda L. Maus DVM
Catalina Pet Hospital
Toxoplasma gondii is a parasite that can infect birds and mammals, including humans. Cats become infected by eating the parasite "egg" or infected small mammals or birds. Cats are the only animal in which Toxoplasma reproduces, with the "eggs" being found in cat feces. However, most cats can clear the infection and do not continue to pass infected feces after a few weeks. Other cats are infected with Toxoplasma for life, with the organism living in their organs or tissue.
In addition to direct exposure to Toxoplasma in cat feces and litter, humans can be exposed when handling raw meat or eating undercooked meat, handling or eating raw vegetables, and handling garden soil without gloves.
The symptoms of Toxoplasma in cats and people can vary from no signs in most patients with a strong immune system to severe diarrhea, heart or lung disease, liver disease, neurologic disease, eye disease, etc in patients with a weak immune system.
A human mother who has been exposed to Toxoplasma prior to pregnancy, who already has antibodies against Toxoplasma which she will pass to her offspring, has a very low risk for her baby to become infected. A human mother with a first time, new exposure and infection due to Toxoplasma has the highest risk for her baby to become severely affected, especially during first trimester. A blood test can be performed by a obstetrician to look for Toxoplasma antibodies in the mother.
While pregnant, in conjunction with passing the litter box duties to another family member, wearing gloves while gardening, hand washing, rinsing produce, and safely handling raw meat and properly cooking meat help prevent exposure to Toxoplasma.