Toxoplasmosis in Cats

Toxoplasmosis is a disease caused by a single-celled intracellular parasite called Toxoplasma gondii. It is a protozoan parasite which can infects multiple of warm blooded animals including humans, livestock, birds and especially cats. However, cats are the definitive hosts in which the parasite is only able to sexually reproduce in cats.

Causes

The life cycle of Toxoplasma gondii has two hosts;

• Definitive host - cats
• Intermediate host – other domestic animals & humans

Parasite can only produce eggs when infecting a cat. When a cat ingests an infected prey or infected raw meat the parasite is released into the cat's digestive tract. The organisms then multiply in the wall of the small intestine and produce eggs. These eggs are then excreted in large numbers in the cat's stool.

Symptoms

• Loss of appetite
• Lethargy
• Weight loss
• Abdominal Pain
• Vomiting
• Diarrhea
• Depression
• Fever
• Shortness of breath
• Uncoordinated gait
• Seizures
• Tremors
• Muscular weakness
• Partial or complete paralysis
• Jaundice
• Inflammation of tonsils - tonsillitis
• Inflammation of retina - retinitis
• Inflammation of middle part of the eye including iris - uveitis
• Inflammation of the cornea – keratitis

Symptoms are most severe in kittens infected while in the womb. These kittens may be stillborn or die before weaning. Those which survive may show lack of appetite, fever, difficulty in breathing, and jaundice

Diagnosis

Based on;  

* History

* Clinical signs

* Laboratory tests: Determine the   levels         of antibodies againt Toxoplasma gondii in the blood

      

      Treatments

Most cats that have toxoplasmosis can recover with treatment. Treatments usually involves a course of an antibiotic called Clindamycin. Other drugs that are used include pyrimethamine and sulfadiazine, which act together to inhibit T. gondii reproduction.

Transmission to Humans

Contact with egg-contaminated soil is the major means by which many different species-rodents, ground-feeding birds, sheep, goats, pigs, and cattle, as well as humans living in developing countries-are exposed to Toxoplasma gondii.

People also become infected by eating unwashed fruits, vegetables and undercooked infected meat particularly lamb and pork. The organism can sometimes be present in some unpasteurized dairy products, such as goat's milk. Toxoplasma gondii can also be transmitted directly from pregnant woman to unborn child when the mother becomes infected during pregnancy.

There are two populations at high risk for infection with Toxoplasma gondii; pregnant women and immune-deficient individuals. Congenital infection is of greatest concern in humans. About one-third to one-half of human infants born to mothers who have acquired Toxoplasma during that pregnancy is infected. The vast majority of women infected during pregnancy have no symptoms of the infection themselves. The majority of infected infants will show no symptoms of toxoplasmosis at birth, but many are likely to develop signs of infection later in life. Loss of vision, mental retardation, loss of hearing, and death in severe cases, are the symptoms of toxoplasmosis in congenitally infected children.

Prevention

There are several general sanitation and food safety steps to reduce the chances of becoming infected with Toxoplasma:

• Do not eat raw or under-cooked meat. Meat should be cooked to a temperature of at least 160°F for 20 minutes.
• Do not drink unpasteurized milk.
• Do not eat unwashed fruits and vegetables.
• Wash hands and food preparation surfaces with warm soapy water after handling raw meat.
• Wear gloves when gardening. Wash hands after gardening
• Wash hands before eating
• Keep children's sandboxes covered
• Do not drink water from the environment unless it is boiled
• Do not feed raw meat or under-cooked meat to cats. Also, do not give them unpasteurized milk
• Do not allow cats to hunt or roam
• Do not allow cats to use a garden or children's play area as their litter box
• Remove feces from the litter box daily and clean with boiling or scalding water
• Pregnant women, and persons with suppressed immune systems, should not clean the litter box
• Control rodent populations and other potential intermediate hosts