Learn about symptoms, causes, treatment and prevention of this parasitic infection that can cause severe disease.
Toxoplasmosis (tok-so-plaz-MOE-sis) is an infection with a parasite called Toxoplasma gondii. People often get the infection from eating undercooked meat. You can also get it from contact with cat feces. The parasite can pass to a baby during pregnancy.
Most people infected with the parasite do not have symptoms. Some people get flu-like symptoms. Serious disease most often affects infants and people with weakened immune systems. Toxoplasmosis during pregnancy may cause miscarriage and birth defects.
Most infections don't need treatment. Drug treatment is used for people with more-serious cases, pregnant people, newborns and people with weakened immune systems. Several steps to prevent toxoplasmosis can lower the risk of infection.
Most people infected with toxoplasmosis do not have any symptoms. They often don't know they're infected. Some people have flu-like symptoms, including:
The toxoplasma parasites may infect tissues of the inner eye. This can occur in people with healthy immune systems. But the disease is more serious in people with weakened immunity. An infection in the eye is called ocular toxoplasmosis. Symptoms may include:
Untreated eye disease can cause blindness.
People with weakened immune systems are likely to have more-serious disease from toxoplasmosis. A toxoplasmosis infection from earlier in life may become active again. People at risk include those living with HIV/AIDS, people receiving cancer treatment and people with a transplanted organ.
In addition to serious eye disease, toxoplasmosis can cause severe lung or brain disease for a person with weakened immunity. Rarely, the infection can show up in other tissues throughout the body.
Lung infection may cause:
Toxoplasmosis may cause inflammation of the brain, also called encephalitis. Symptoms may include:
Toxoplasmosis can pass from the mother to the fetus during a pregnancy. This is called congenital toxoplasmosis.
Infection during the first trimester often causes more-severe disease. It also may result in miscarriage. For some babies with toxoplasmosis, serious disease may be present at birth or appear early in infancy. Medical problems may include:
Symptoms of severe disease vary. They may include:
Most babies with toxoplasmosis do not show symptoms. But problems may show up later in childhood or teenage years. These include:
Talk to your health care provider about a test if you are worried about exposure to the parasite. If you are planning a pregnancy or are pregnant, see your provider if you suspect exposure.
The symptoms of severe toxoplasmosis include blurred vision, confusion and loss of coordination. These need immediate medical care, particularly if you have a weakened immune system.
Toxoplasma gondii is a parasite that can infect most animals and birds. It can only go through the entire cycle of reproduction in domestic and wild cats. These are the main hosts for the parasite.
Immature eggs, a middle stage of reproduction, can be in the feces of cats. This immature egg allows for the parasite to make its way through the food chain. It can pass from soil and water to plants, animals and humans. Once the parasite has a new host, the reproduction cycle goes on and causes an infection.
If you're in typical health, your immune system keeps the parasites in check. They stay in your body but are not active. This often gives you lifelong immunity. If you're exposed to the parasite again, your immune system would clear it out.
If your immune system is weakened later in life, parasite reproduction can start again. This causes a new active infection that can lead to serious disease and complications.
People often get a toxoplasma infection one of the following ways:
The parasite is found throughout the world. Anyone can become infected.
Risks of serious disease from toxoplasmosis include things that prevent the immune system from fighting infections, such as:
Certain precautions can help prevent toxoplasmosis:
If you're pregnant or otherwise at risk of toxoplasmosis, take these steps to protect yourself:
A diagnosis of toxoplasmosis is based on blood tests. Laboratory tests can detect two types of antibodies. One antibody is an immune system agent that is present during a new and active infection with the parasite. The other antibody is present if you had an infection at any time in the past. Depending on the results, your health care provider may repeat a test after two weeks.
More diagnostic tests are used depending on other symptoms, your health and other factors.
If you have eye symptoms, you will need an exam by a doctor who specializes in eye disease, called an ophthalmologist. An exam may include the use of special lenses or cameras that allow the doctor to see tissues inside the eye.
If there are symptoms of brain inflammation, tests might include the following:
In the United States, pregnant people are not routinely screened for toxoplasmosis. Recommendations for screening vary in other countries.
Your health care provider may order a diagnostic blood test for you if:
If you have an active infection, it may pass to your baby in the womb. A diagnosis is based on tests of the fluid surrounding the baby, called amniotic fluid. The sample is taken with a fine needle that goes through your skin and into the fluid-filled sac holding the baby.
Your care provider will order a test if:
Blood tests are ordered for diagnosis of toxoplasmosis in a newborn baby if infection is suspected. A baby who tests positive will have many tests to detect and keep an eye on the disease. These would likely include:
Medication is used to treat active infections. How much and how long you take medicine depends on different factors. These include how seriously ill you are, your immune system health and where the infection is located. Your stage of pregnancy is also a factor.
Your provider may give you a combination of prescription drugs. They include:
Drug treatment for infants may last 1 to 2 years. Regular and frequent follow-up appointments are needed to watch for side effects, vision problems, and physical, intellectual and overall development.
In addition to the regular drug treatment, eye disease also may be treated with anti-inflammatory steroids called glucocorticosteroids.
You're likely to start by seeing your health care provider. If you're pregnant, you'll likely see your obstetrician. You also may see a provider who specializes in fetal health, called a perinatologist. In some cases, you'll see a provider who specializes in infectious diseases.
You can prepare for your appointment by being ready to answer the following questions: