Toxoplasmosis: A-to-Z Guide from Diagnosis to Treatment to Prevention

Introduction to toxoplasmosis:

The idea of not changing kitty litter during pregnancy has made it into popular culture, but the litter box is not the way that pregnant moms are most likely to get toxoplasmosis — one infection that they do not want to get while pregnant.

Pregnant woman's belly. Toxoplasmosis is an issue for pregnant women.

What is toxoplasmosis?

Toxoplasma gondii is a one-celled parasite that sometimes causes devastating effects on unborn children if their mothers become infected for the first time during their pregnancy.

Toxoplasmosis is the name of the disease caused by the parasite. It is one of the TORCHS congenital infections (toxoplasmosis, other, rubella, CMV, herpes, syphilis). They are among the leading causes of birth defects and newborn deaths. They often cause eye problems.

Who gets toxoplasmosis?

The parasites that cause toxoplasmosis are found widely in the soil. They are able to infect most types of mammals, but cats are the preferred hosts.

Cats become infected by eating mice or other small animals, or by being fed uncooked meats. The parasites reproduce in the intestines of cats, and egg cysts are found in their stools.

When sheep, pigs, or cattle become infected, they remain infected for the rest of their lives. Undercooked pork, beef, or lamb is often infectious.

People are most likely to get toxoplasmosis from eating undercooked meat. They can also get it by accidentally getting egg spores into their mouths, either from litter boxes, the soil, infected food, or food that has become contaminated (such as unwashed fruits or vegetables).

Those with HIV are at particular risk for toxoplasmosis, and may pass it along to an unborn child regardless of whether or not they’ve been infected before.

What are the symptoms of toxoplasmosis?

Children born with congenital toxoplasmosis may be very sick or even dead at the time of birth. Symptoms might include excessive jaundice, poor feeding, rash, seizures, or an enlarged liver and spleen.

The great majority of children born with congenital toxoplasmosis have no symptoms at the outset. Still, many of these children will go on to have developmental delay and/or vision problems.

Most people who get toxoplasmosis after birth have no symptoms at all. Some have non-specific viral-like symptoms such as a fever, sore throat, and muscle aches. Some have one or more swollen glands.

Less commonly, children may have a mono-like illness, or an eye infection with blurred vision.

More severe disease is rare, but can happen, especially in those who are immunocompromised.

Is toxoplasmosis contagious?

Toxoplasmosis can be spread from mother to child. It has also been shown to be spread through blood transfusions and organ transplantations. Otherwise, it does not spread directly from person to person.

How long does toxoplasmosis last?

Symptoms of an acute episode of toxoplasmosis, if any, are usually gone in about 7 days. Cysts remain in the body for life.

The effects of congenital toxoplasmosis are also life-long.

How is toxoplasmosis diagnosed?

Blood tests are usually used to diagnose toxoplasmosis.

How is toxoplasmosis treated?

Treatment of a first infection during pregnancy is recommended, with anti-parasite drugs. Also, those with congenital toxoplasmosis should be treated, often for an entire year.

Those who are immunocompromised may also require treatment, but most others do not, unless they have significant symptoms.

How can toxoplasmosis be prevented?

Cooking all meat thoroughly (until it is no longer pink) is the cornerstone of prevention. All raw meats, unwashed fruits and vegetables, and the surfaces they touch should be considered contaminated. Wash hands and surfaces after any such contact and before further cooking or eating.

Prevent cats from becoming infected by not feeding them undercooked meats and by preventing them from hunting wild rodents (especially while a woman in the house is pregnant – cats shed egg-cysts in the stool for only about 2 weeks after becoming infected).

Pregnant women should avoid cat feces (as in gardening or changing litter boxes). Wearing gloves and washing thoroughly helps reduce exposure. Also, having the litter box changed daily reduces the risk, because the egg-cysts do not become infective for 2 or 3 days in the stool.

Related concepts:

Toxoplasma gondii

Dr. Greene is a practicing physician, author, national and international TEDx speaker, and global health advocate. He is a graduate of Princeton University and University of California San Francisco.

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