Toxoplasmosis is a disease caused by an inflammation of the organism called Toxoplasma gondii (T. gondii). This is a microscopic single-celled organism similar to coccidia. Virtually all warm-blooded animals, including humans, may be infected with this protozoan. It is an exceptionally well-adapted parasite that seldom causes serious illness to the individuals it infects.

Toxoplasma occurs worldwide and cat infection is equally widespread. Many cats are infected but sometimes they show no signs. Infection rates are higher among free-roaming and feral cats. In comparison, infection is rare in pet cats that do little to no hunting and those who are mainly or exclusively fed commercial cat foods.

Signs and Symptoms

Signs of this infection include:

  • Fever
  • loss of appetite
  • weight loss
  • lethargy
  • Pneumonia causing breathing difficulties
  • Inflammatory eye problems
  • Liver disease causing jaundice
  • Neurological signs (e.g. tremors or seizures)

Less common signs of illness reported include:

  • lymph node enlargement
  • vomiting and diarrhea
  • muscle pain

Infection in a pregnant cat can cause serious signs of illness in the kittens, such as fetal death, miscarriage, stillbirth and death of young kittens, but this is rare.

Diagnosis

Clinical toxoplasmosis diagnosis is complicated and requires specific veterinary tests. The suspected diagnosis may be made by testing antibodies to toxoplasmosis in the blood. There are two of them: IgM and IgG. A high IgG count means that a cat has previously been infected but is now presumably immune. High or increasing IgM counts indicate that there is an existing clinical infection. At present, only a positive response to treatment helps with this diagnosis.

Causes

Toxoplasmosis infection in cats is caused by the parasite Toxoplasma gondii. Cats are the main host for these parasites, but infants, adults, and other animals can also be infected. Humans and animals can become infected if they ingest microscopic parasite eggs or eat cysts in undercooked meat from cattle, sheep, pigs or wild animals such as deer.

Treatment

Treatment typically requires a course of antibiotics called clindamycin, either single dose or in conjunction with corticosteroids, if there is severe inflammation of the eyes or of the central nervous system. Ideally, treatment should be begun soon after diagnosis and should be continued for several days until the symptoms have completely vanished. In acute illness, treatment is always initiated on the basis of high initial levels of IgM antibodies. If no clinical progress is observed within two to three days, the diagnosis of toxoplasmosis may be reviewed.

Precautions and Care

Take the precautions listed below to protect yourself and your cat.

  • Keep your cat inside-do not permit your cat(s) to hunt rodents and birds.
  • Stop raw food. Just feed cooked meat or canned food to your cats.
  • Change the cat litter every day before it becomes contagious.
  • Dispose the used litter safely, preferably in a sealed plastic bag.
  • If your cat has long fur on the back or if the cat is too fat, sick or arthritic to adequately groom itself, carefully trim their hair (wash your hands afterwards) or get your cat professionally groomed to keep them healthy.