Toxoplasmosis – Caution During Pregnancy

Toxoplasmosis is an infectious disease that primarily affects cats. Humans are considered intermediate hosts, though they usually do not exhibit any clinical symptoms. However, a primary infection during pregnancy is truly dangerous. It can lead to severe fetal malformations and miscarriages.

INHALT
Cause and Origin Symptoms Diagnosis Treatment Prevention
Cause and Origin

The causative agent of toxoplasmosis is a single-celled parasite whose primary host is the cat. Cats excrete certain developmental stages of the toxoplasma, which can survive in the external environment as resilient spores for up to several years. These can then be ingested either by another cat or by an intermediate host. Since humans are one of the intermediate hosts, this is a zoonosis (see related article).

Due to the many different intermediate hosts and the pathogen’s resilience in the environment, many other sources of infection play an important role for humans in addition to cats, such as raw and undercooked pork and lamb, unwashed vegetables, unpasteurized goat’s milk, contaminated soil, or sandboxes soiled by cat feces.

Symptoms

Whether the disease breaks out and clinical symptoms appear in the cat depends primarily on the type of infection. When cats infect each other, clinical symptoms rarely develop; however, infection via an intermediate host almost always leads to the onset of the disease.

Older cats, if at all, show only mild signs of illness, such as mild diarrhea. Once infected, cats become immune to the pathogen and no longer shed any developmental stages. In younger or immunocompromised cats, however, far more pronounced symptoms may occur. These include diarrhea, swollen lymph nodes, coughing, breathing difficulties, jaundice, eye infections, inflammation of the heart and skeletal muscles, as well as the meninges (see article on meningoencephalitis). Sudden deaths also occur in kittens.

Chronic toxoplasmosis can only develop in cats with a compromised immune system. This is characterized by gait disturbances, seizures, weight loss, digestive problems, and eye inflammation.

Diagnosis

Since most cats show no or very few symptoms during a toxoplasmosis infection, they are rarely brought to the veterinarian’s office. Instead, the focus is on determining whether an otherwise healthy cat is shedding developmental stages of Toxoplasma. This can be detected through a fecal examination, but only during a roughly three-week period following initial infection. This primarily affects kittens, although overall only about one to two percent of all cats shed Toxoplasma.

Litter box
An infected cat can shed stages of the Toxoplasma parasite in its feces
Treatment

In adult cats, treatment is usually not necessary because symptoms are often mild. The infection is often discovered by chance during other examinations. In young or immunocompromised cats with more severe cases, treatment with antiparasitic and antibiotic medications is necessary.

Prevention

The best way to effectively protect your cat from toxoplasmosis is to feed it either commercial cat food or meat that has been thoroughly cooked or frozen for an extended period of time. This approach can significantly reduce the risk of infection, at least for indoor-only cats. However, because outdoor cats may come into contact with rodents, the risk of infection cannot be completely ruled out.