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by Rosenblum L


Toxoplasmosis is passed from animals to humans. People can contract it by:
A pregnant woman who gets toxoplasmosis for the first time may pass it to her unborn child. Active infection usually occurs one time in a person’s life, although the protozoon remains inactive in the body. Generally, if a woman has become immune to the infection before getting pregnant, she will not pass the condition to her baby.


Most people do not have symptoms. Those who do have symptoms may have:
People with weakened immune systems may have toxoplasmosis infections in multiple organs. Infection is most common in the brain (encephalitis), eyes (chorioretinitis), and lungs (pneumonitis). Symptoms may include:
  • Fever
  • Seizures
  • Headache
  • Visual defects
  • Problems with speech, movement, or thinking
  • Mental illness
  • Shortness of breath
Swollen brain
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In babies, the severity of symptoms depends on when the mother became infected during pregnancy. If infection occurs during the first three months of pregnancy, babies are less likely to become infected. But if they do, then their symptoms are much more severe. During the last six months, babies are more likely to become infected. But, their symptoms are less serious. Toxoplasmosis can also cause miscarriage or stillbirth.
About one in 10 babies born with toxoplasmosis has severe symptoms. These include:
Many babies infected with toxoplasmosis may seem healthy at birth. But they may develop problems months or years later. These include:


Centers for Disease Control and Prevention



Health Canada

Women's Health Matters



Parasites—toxoplasmosis (toxoplasma infection). Centers for Disease Control and Prevention website. Available at: Updated February 1, 2012. Accessed January 13, 2013.

Perinatal viral and parasitic infections. ACOG Practice Bulletin. 2000. No. 20. American College of Obstetricians and Gynecologists website. Available at:

Toxoplasmosis. Nemours website. Available at: Updated September 2011. Accessed January 7, 2013.


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