Toxoplasmosis

Toxoplasmosis is a disease caused by a single-celled parasite called Toxoplasma gondii.  It is most commonly transmitted to humans through eating contaminated foods or through handling the feces of infected cats (or soil or water contaminated by the feces of infected cats).

More than 40 million people in the United States may be infected with the Toxoplasma parasite. Of those who are infected, very few have symptoms because a healthy person’s immune system usually keeps the parasite from causing illness. However, pregnant women and individuals who have compromised immune systems should be cautious; for them, a Toxoplasma infection could cause serious health problems.

Can Toxoplasma infection be transmitted through breast milk?

No. There are no studies documenting transmission of Toxoplasma gondii in humans through breast milk. However, a woman who is newly infected with Toxoplasma during pregnancy can pass the infection to her fetus. The woman may not have symptoms, but there can be severe consequences for her infant at birth or later in life, such as blindness, brain damage, or mental disability.

Visit CDC’s page on Toxoplasmosis in pregnant women for additional information and resources.

Is it safe for a mother to breastfeed her infant if she contracted a Toxoplasma infection during her pregnancy?

Usually. There are no studies documenting transmission of Toxoplasma gondii in humans through breast milk. When a mother is infected during pregnancy, Toxoplasma may be circulating in her blood. If a breastfeeding woman has cracked and bleeding nipples or her breasts are inflamed, she might have some blood in her breast milk. Although it has never been documented, it is possible that Toxoplasma gondii could be in that blood and infect the infant through her breast milk. However, the likelihood of human milk transmission is very small.

How can mothers protect themselves and their infants from toxoplasmosis?

There are several food safety measures and environmental precautions mothers can take to help prevent Toxoplasma infection. These include cooking meats to safe temperatures, washing and peeling fruits and vegetables, wearing gloves while gardening, changing the cat litter daily, and practicing proper handwashing techniques consistently.