The Symptoms and Treatment of Toxoplasmosis

What is toxoplasmosis?

Toxoplasmosis is a parasitic infection caused by a parasite called Toxoplasma gondii, which is found in humans and some types of animals. Although this parasite can infect all warm-blooded animals, it tends to only reproduce in the gut of felids, such as domestic cats and other members of the Felidae family. This parasite thrives and sexually reproduces inside of cats before being excreted in the cats' feces. Thus, it would make cats as the parasite's definitive hosts. 

Aside from cat feces, Toxoplasma gondii can also be found in contaminated soil, water, dust, raw or undercooked meat, and unwashed fruits and vegetables. The three genotypes of Toxoplasma gondii are types I, II, and III. In Europe and USA, most cases of toxoplasmosis that fetuses contract in the womb is the type II genotype. 

Approximately one-third of the world's population is affected by toxoplasmosis. Most people only have mild symptoms, while some do not have any symptoms at all. It usually depends on how strong an individual's immune system is. However, there are also reports of severe toxoplasmosis cases. 

Symptoms

Toxoplasmosis can cause symptoms that are similar to those of the flu. However, most healthy individuals with toxoplasmosis show no signs or symptoms of infection. Most of them are not even aware that they have it. The flu-like symptoms of toxoplasmosis may include:

• Headaches
• Fever
• Body aches
• Fatigue
• Swollen lymph nodes

Immunocompromised individuals

If you had toxoplasmosis before, the infection may be reactivated, especially if you are undergoing chemotherapy, had a recent organ transplant, or if you have HIV/AIDS. In such cases, severe signs and symptoms may be experienced, which include:

• Headaches
• Seizures
• Mental confusion
• Lung and vision problems
• Poor coordination

Infants

For mothers who are infected with toxoplasmosis for the first time during pregnancy or just before pregnancy, they can pass the infection to their baby even if they are asymptomatic. This transplacental acquisition of T. gondii is called congenital toxoplasmosis.

When mothers are infected during their third trimester, their baby has an increased risk of contracting the infection, and have the least risk when they are infected during their first trimester. However, the earlier the infection, the more crucial it is for the baby since a number of early infections end in a miscarriage or stillbirth. In some cases, infants may survive but are born with serious health problems, which include:

• Hepatomegaly (enlarged liver) and splenomegaly (enlarged spleen)
• Jaundice (yellowing of the skin and whites of the eyes)
• Severe infection of the eyes
• Seizures

Usually, babies who are born with toxoplasmosis are asymptomatic at birth, except for a low birth weight or premature birth. They may later show signs and symptoms of the disease, such as mental disability, hearing loss, or eye infections during their teenage years or young adulthood.

Causes

The parasite that causes toxoplasmosis is T. gondii. You can get infected with this parasite after consuming raw or undercooked meat as well as drinking contaminated water. T. gondii can also be found in unwashed fruits and vegetables that are contaminated with manure. For this reason, it is very important to always wash your produce to prevent contracting this parasitic infection.

This parasite is often found in cat feces since T. gondii sexually reproduces inside a cat’s body. Its eggs are excreted from the cat’s body through defecation. Even though cats are definitive hosts of the parasite, they usually do not show any symptoms of the disease.

If people accidentally ingest this parasite, they become infected with toxoplasmosis. Transmission mostly happens when individuals are exposed to a cat’s parasite-containing feces when cleaning a litter box and not washing their hands afterward. For this reason, pregnant women are highly advised not to clean their cat’s litter box to prevent the possible transmission of the disease to their unborn child. A good preventive measure is to wear gloves when cleaning your cat’s litter box. You should also clean litter boxes every day since it takes 1-5 days for the parasite to become infectious after it has been excreted.

However, in the United States, humans rarely get toxoplasmosis from cats. The most common way of contracting the parasite is through the consumption of raw or undercooked meat and unwashed fruits and vegetables. Most indoor cats do not have T. gondii in their gut. Cats that hunt outdoors are more likely to be infected with the parasite. 

Treatment

Treatment is not usually required for people who are asymptomatic and those who only have mild and self-limiting symptoms. However, in severe infections that cause problems in the internal organs and eyes, doctors usually prescribe sulfadiazine, which is an antibiotic, and pyrimethamine (Daraprim), a medication used for the treatment of malaria.

For individuals who have HIV/AIDS, taking these medications may be lifelong. Your doctor may also prescribe B vitamins since pyrimethamine tends to decrease folic acid levels. 

Treatment for Pregnant Women

There is a different treatment approach for pregnant women with toxoplasmosis. Treatment usually depends on the severity of infection and whether the fetus is infected. Doctors usually discuss the best treatment for each pregnancy case.

During the first and second trimesters, pregnant women usually take the antibiotic called spiramycin. In the late second and third trimesters, leucovorin and a combination of pyrimethamine/sulfadiazine are usually prescribed.

If the fetus is infected with toxoplasmosis, the treatment of choice is pyrimethamine and sulfadiazine. However, these drugs can cause liver toxicity and bone marrow suppression. For this reason, these drugs are used when they are the only options left.  

Prevention

Toxoplasmosis can be prevented by:

• Wearing gloves when cleaning cat litter and washing your hands afterward.
• Cooking all meat properly.
• Washing fresh produce before consumption.
• Washing all kitchen utensils that handled raw meat.
• During pregnancy, pregnant women must avoid cleaning their cat’s litter box. 

Outlook

The outlook for individuals who have this parasitic infection would depend on various factors. Pregnant women with toxoplasmosis should work closely with their doctor to help find the suitable treatment plan for them. Treatment for babies who are born with this infection usually lasts for a year. 

Children and individuals who are immunocompromised, such as those who have HIV/AIDS, may require hospitalization for treatment to prevent developing other complications. 

Individuals without underlying health problems and women who are not pregnant usually recover after several weeks. Treatment may be unnecessary if you are healthy and only have mild symptoms.