Toxoplasma infection - including symptoms, treatment and prevention
Toxoplasma infection is caused by a parasite Toxoplasma gondii. The parasite occurs worldwide and infection is very common.
How toxoplasmosis is spread
The parasite is carried by cats and shed in cat faeces. It is also carried in the muscles of infected:
- rodents (for example rats and mice)
- other warm blooded animals (including birds).
Human infection occurs when the parasite is taken in by mouth. This most often results from eating raw or undercooked meat or unwashed salad vegetables, but also if hands become contaminated with cat faeces during gardening or cleaning cat litter trays. Eggs of the parasite may survive in moist soil for over a year.
Signs and symptoms
Toxoplasma infection usually does not cause any symptoms. Occasionally fever and swollen glands can occur. Following recovery from an infection, a few parasites remain in tiny cysts in the muscles, lung, brain or other organs. If the immune system is severely damaged, for example by advanced human immunodeficiency virus (HIV) infection, organ transplants, or treatment for some cancers, the parasites in the cyst may reactivate and can cause serious illness.
If a woman becomes newly infected with Toxoplasma during pregnancy, the fetus also can become infected and suffer birth defects. Fetal infection occurs when parasites in the infected mother’s blood stream cross the placenta and enter the fetus. Reactivation of a previous Toxoplasma infection can also occur in pregnancy but the fetus is rarely affected.
Diagnosis is made by a series of blood tests, sometimes by PCR (polymerase chain reaction) tests or by examining tissue with a microscope in a pathology laboratory.
(time between becoming infected and developing symptoms)
5 to 23 days.
(time during which an infected person can infect others)
Except for transmission from a pregnant woman to her fetus, person-to-person spread does not occur.
Antibiotic treatment is available for significant infections, including treatment during pregnancy, if necessary.
- Exclusion from childcare, preschool, school or work is not necessary.
- Avoid eating and minimise handling raw meat.
- Cooking all meat thoroughly and washing hands and utensils after handling raw meat. All meat eaten by pregnant women should be cooked 'well done'.
- Wash all vegetables thoroughly before eating, especially salad vegetables.
- Use gloves when emptying cat litter trays. Trays can be disinfected with boiling water. Eggs need over 24 hours to become infectious after being passed in the faeces, so clean litter trays daily. Cover sandpits when not in use, to prevent cats from using them as litter.
- Cats should be fed dry, canned or cooked food. Discourage pet cats from hunting. Since eating rodents and birds infects cats, pet cats that do not hunt will not be exposed and do not pose a risk to their owners. Even if a cat does become exposed, it only sheds infective eggs in its faeces for about 10 days.
- Wear gloves when gardening. Hands should be washed thoroughly with soap and warm running water after contact with soil.
- Preventing food poisoning at home
- Handling and preparing food
- Hand hygiene
- Keeping areas clean
- Thawing, cooking, cooling and reheating food
- Personal hygiene and food safety