Overview Of Toxoplasmosis

Toxoplasmosis is an infection due to the parasite Toxoplasma gondii.

Causes Of Toxoplasmosis

Toxoplasmosis is found in humans worldwide and in many kinds of animals and birds. The parasite also lives in cats.

Human infection may result from:

  • Blood transfusions or solid organ transplants
  • Handling cat litter
  • Eating contaminated soil
  • Eating raw or undercooked meat (lamb, pork, and beef)
  • Toxoplasmosis also affects people who have weakened immune systems. These people are more likely to have symptoms.

The infection may also be passed from an infected mother to her baby through the placenta. This results in congenital toxoplasmosis.


There may be no symptoms. If there are symptoms, they usually occur about 1 to 2 weeks after contact with the parasite. The disease can affect the brain, lung, heart, eyes, or liver.

Symptoms in people with otherwise healthy immune systems can include:

  • Enlarged lymph nodes in the head and neck
  • Headache
  • Fever
  • Mild illness similar to mononucleosis
  • Muscle pain
  • Sore throat

Symptoms of toxoplasmosis in people with a weakened immune system can include:

  • Confusion
  • Fever
  • Headache
  • Blurred vision due to inflammation of the retina
  • Seizures

Exams & Tests

The health care provider will perform a physical exam. Tests that may be done include:

  • Blood test for toxoplasmosis
  • CT scan of the head
  • MRI of head
  • Slit-lamp exam of the eyes
  • Brain biopsy

Treatment Of Toxoplasmosis

People without symptoms usually do not need treatment.

Medicines to treat the infection include an antimalarial drug and antibiotics. People with AIDS should continue treatment for as long as their immune system is weak, to prevent the disease from reactivating.