Toxoplasmosis is an infection due to the parasite Toxoplasma gondii.
Toxoplasmosis is found in humans worldwide and in many kinds of animals and birds. The parasite 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.
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 persons with otherwise healthy immune systems can include:
- Enlarged lymph nodes in the head and neck
- Mild illness similar to mononucleosis
- Muscle pain
- Sore throat
Symptoms in people with a weakened immune system can include:
Exams and Tests
The doctor or nurse will perform a physical exam. Tests that may be done include:
Persons without symptoms usually do not need treatment.
Medicines to treat the infection include an antimalarial drug and antibiotics. AIDS patients should continue treatment for as long as their immune system is weak to prevent the disease from reactivating.
With treatment, people with a healthy immune system usually recover well.
The disease may return.
In people with a weakened immune system, the infection may spread throughout the body, leading to death.
When to Contact a Medical Professional
Call for an appointment with your health care provider if you develop symptoms of toxoplasmosis. Immediate medical care is needed if symptoms occur in:
- Infants or babies
- Someone with a weakened immune system due to certain medications or disease
Immediate medical treatment is also needed if the following symptoms occur:
Tips for preventing this condition:
- Do not eat undercooked meat.
- Wash hands after handling raw meat.
- Keep children's play areas free from cat and dog feces.
- Wash your hands thoroughly after touching soil that may be contaminated with animal feces.
Pregnant women and those with weakened immune systems should take the following precautions:
- Do not clean cat litter boxes
- Do not touch anything that may contain cat feces
- Do not touch anything that could be contaminated by insects exposed to cat feces (cockroaches, flies, etc.)
Pregnant women and those with HIV should be screened for toxoplasmosis. A blood test can be done.
Montoya JG, Boothroyd JC, Kovacs JA. Toxoplasma gondii. In: Mandell GL, Bennett JE, Dolin R, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 279.
Reviewed By: Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.