Diagnosis
A Toxoplasma-positive reaction, stained by immunofluroescence (IFA). (CDC Photo)
The diagnosis of toxoplasmosis is typically made by serologic testing. A test that measures immunoglobulin G (IgG) is used to determine if a person has been infected. If it is necessary to try to estimate the time of infection, which is of particular importance for pregnant women, a test which measures immunoglobulin M (IgM) is also used along with other tests such as an avidity test.
Diagnosis can be made by direct observation of the parasite in stained tissue sections, cerebrospinal fluid (CSF), or other biopsy material. These techniques are used less frequently because of the difficulty of obtaining these specimens.
Parasites can also be isolated from blood or other body fluids (for example, CSF) but this process can be difficult and requires considerable time.
Molecular techniques that can detect the parasite's DNA in the amniotic fluid can be useful in cases of possible mother-to-child (congenital) transmission.
Ocular disease is diagnosed based on the appearance of the lesions in the eye, symptoms, course of disease, and often serologic testing.

Treatment

Healthy people (nonpregnant)

Most healthy people recover from toxoplasmosis without treatment. Persons who are ill can be treated with a combination of drugs such as pyrimethamine and sulfadiazine, plus folinic acid.

Pregnant women, newborns, and infants

Pregnant women, newborns, and infants can be treated, although the parasite is not eliminated completely. The parasites can remain within tissue cells in a less active phase; their location makes it difficult for the medication to completely eliminate them.

Persons with ocular disease

Persons with ocular toxoplasmosis are sometimes prescribed medicine to treat active disease by their ophthalmologist. Whether or not medication is recommended depends on the size of the eye lesion, the location, and the characteristics of the lesion (acute active, versus chronic not progressing).

Persons with compromised immune systems

Persons with compromised immune systems need to be treated until they have improvement in their condition. For AIDS patients, continuation of medication for the rest of their lives may be necessary, or for as long as they are immunosuppressed.

Prevention & Control

People who are healthy should follow the guidelines below to reduce risk of toxoplasmosis. If you have a weakened immune system, please see guidelines for Immunocompromised Persons.

Reduce Risk from Food

To prevent risk of toxoplasmosis and other infections from food:

• Cook food to safe temperatures. A food thermometer should be used to measure the internal temperature of cooked meat. Do not sample meat until it is cooked. USDA recommends the following for meat preparation.
• For Whole Cuts of Meat (excluding poultry)
• Cook to at least 145° F (63° C) as measured with a food thermometer placed in the thickest part of the meat, then allow the meat to rest* for three minutes before carving or consuming.
• For Ground Meat (excluding poultry)
• Cook to at least 160° F (71° C); ground meats do not require a rest* time.
• For All Poultry (whole cuts and ground)
• Cook to at least 165° F (74° C), and for whole poultry allow the meat to rest* for three minutes before carving or consuming.

*According to USDA, "A 'rest time' is the amount of time the product remains at the final temperature, after it has been removed from a grill, oven, or other heat source. During the three minutes after meat is removed from the heat source, its temperature remains constant or continues to rise, which destroys pathogens."

• Freeze meat for several days at sub-zero (0° F) temperatures before cooking to greatly reduce chance of infection.
• Peel or wash fruits and vegetables thoroughly before eating.
• Wash counter tops carefully. Photo courtesy of USDA.
• Wash cutting boards, dishes, counters, utensils, and hands with hot soapy water after contact with raw meat, poultry, seafood, or unwashed fruits or vegetables.

The U.S. Government and the meat industry continue their efforts to reduce T. gondii in meat.

Reduce Risk from the Environment

To prevent risk of toxoplasmosis from the environment:

• Avoid drinking untreated drinking water.
• Wear gloves when gardening and during any contact with soil or sand because it might be contaminated with cat feces that contain Toxoplasma. Wash hands with soap and warm water after gardening or contact with soil or sand.
• Teach children the importance of washing hands to prevent infection.
• Keep outdoor sandboxes covered.
• Have someone else clean the litter box. (CDC Photo)
• Feed cats only canned or dried commercial food or well-cooked table food, not raw or undercooked meats.
• Change the litter box daily if you own a cat. The Toxoplasma parasite does not become infectious until 1 to 5 days after it is shed in a cat's feces. If you are pregnant or immunocompromised:
• Avoid changing cat litter if possible. If no one else can perform the task, wear disposable gloves and wash your hands with soap and warm water afterwards.
• Keep cats indoors.
• Do not adopt or handle stray cats, especially kittens. Do not get a new cat while you are pregnant.