Toxoplasmosis is one of the most common parasitic diseases in warm-blooded animals. Although the single-celled parasite called toxoplasma gondii, which is responsible for this disease, is common in cats, it rarely causes significant clinical diseases in them. Cats act as the primary hosts for toxoplasma gondii. In fact, they are the only mammals in which this parasite is passed through the feces.
In cats, the reproductive form of this parasite lives in the intestine, while infective oocysts exit the body through the feces. Oocysts become infective in 1 - 5 days. They can survive in the environment for several years, showing resistance to most disinfectants. On consumption of infected intermediate prey, the parasite is once again released in the cat's intestine and its life cycle is repeated.
The main sources of infection for cats are uncooked meat and infected prey. Kittens are more susceptible to the infection and show more severe symptoms when infected. Cats which hunt wildlife are also at higher risk of getting infected. Pet cats are less likely to get affected, as they mostly consume hygienic and cooked food.
Causes and symptoms
Cats generally become infected with the consumption of oocysts, which are present in the tissue of chronically infected prey, like rodents and birds, and undercooked meat. Cats don't show any evident signs of infection, except for some clinical symptoms, like lethargy and loss of appetite. Usually, the symptoms occur in kittens and young cats. In humans, severe symptoms include pneumonia, hepatitis, and diarrhea. A person with toxoplasmosis infection may also suffer from depression, partial or total blindness, increased respiratory rate and effort, jaundice, and muscle pain.
Toxoplasmosis is usually diagnosed on the basis of its medical history, signs of illness, and results of laboratory tests. It usually involves a routine blood test. The vet could also perform various diagnostic tests like Complete Blood Count (CBC), fecal examination, ocular examination, IgG and IgM antibody testing, Cerebrospinal Fluid Analysis (CSF Analysis), and analysis of pleural or peritoneal fluid. Sometimes the oocysts can be found in the feces, but this does not confirm the diagnosis as they look similar to some other parasites. A microscopic examination of tissues is required for definitive diagnosis of the condition.
The treatment for toxoplasmosis usually involves a course of an antibiotic called clindamycin. Drugs like trimethoprim-sulfonamide or sulfonamides are also used for the treatment in combination with pyrimethamine. These drugs inhibit the reproduction of the parasite. It is necessary to start the treatment as soon as the disease is diagnosed, and continue it for some days after the symptoms have disappeared. At home, medication provided by the veterinarian should be strictly administered.
For the prevention of this disease, cats should only be fed dry, canned, or cooked food. Uncooked meat, entrails, or bones should be avoided, as these tissues may contain toxoplasma cysts. At the same time, trash containers should also be kept away from them in order to prevent garbage scavenging.