Pet health 101: What is toxoplasmosis and can it be dangerous for cats or cat owners?

Toxoplasmosis can cause disease in the unborn child of a pregnant women.

Toxoplasmosis is a disease commonly associated with cats. Toxoplasmosis, sometimes called simply toxo, is also well known as causing disease in people, particularly in pregnant woman, where the disease is especially dangerous for the unborn child.

What is toxoplasmosis?

Toxoplasmosis is a disease which is caused by the protozoan (one-celled organism) parasite known as Toxoplasma gondeii.

In cats, toxoplasmosis usually causes very mild clinical signs, if any symptoms are seen at all. Symptoms sometimes noted in cats infected with toxoplasmosis are fever, stiffness, joint pain, abdominal pain and swollen lymph nodes. The symptoms are often mild and "flu-like" and may pass unnoticed by the cat owner.

Spread of toxoplasmosis to cats and people

Infected animals, including cats, pass Toxoplasma oocysts (eggs) in their feces and ingestion of infected feces can pass the infection to other animals or to people.

Toxoplasmosis can also be spread through ingestion of the encysted Toxoplasma organisms in meat which is raw or not cooked properly. Therefore, cats which hunt or eat raw meat are susceptible to the disease.

Toxoplasmosis, cats and pregnant women

Cats generally shed Toxoplasma oocysts in their feces when initially infected and usually continue passing the oocysts for up to 2 weeks. Infected cats do not generally shed oocysts again unless they become immunosuppressed (such as when taking immunosuppressive drugs such as cyclosporine).

Toxoplasmosis in people generally causes only mild flu-like symptoms in most cases, much like in cats. However, in pregnant women and immuno-compromised people (those undergoing cancer treatment or other types of immunosuppressive treatment or those suffering from HIV), toxoplasmosis can become more serious.

In pregnant worman, toxoplasmosis can cause disease in the unborn child, causing the child to be aborted or stillborn or born with birth defects.

Preventing toxoplasmosis in pregnancy

Women infected with toxoplasmosis during pregnancy are most likely to have resulting problems. Those infected prior to becoming pregnant are not likely to pass the disease to their child. Therefore, those women not previously infected with toxoplasmosis should avoid exposure to the disease during pregnancy.

Pregnant women should not clean or other otherwise handle the litter box if possible. If unavoidable, she should wear gloves when handling the litter or litter box and clean the box daily. (Toxoplasma oocysts require 48 hours to become infective.) Hands should be washed thoroughly after handling either cats or cat litter. Cat litter should never be disposed of in the garden area.

Cats should not be allowed to hunt, should not be fed raw meat and should not be offered raw, unpasteurized milk.

Pregnant women should also avoid drinking raw milk (especially goat's milk) and should avoid eating undercooked meat. Wearing gloves when gardening or working in the yard is recommended to avoid contact with oocysts in soil.

Food-producing animals can also become infected with toxoplasmosis and can pass the disease to people. Therefore, cats should not be allowed in areas where food-producing animals are kept to avoid the potential for infection.

Though toxoplasmosis can cause serious problems for an unborn child, it is generally not necessary for a pregnant woman to give up her household cats as long as simple precautions are taken to avoid infection with toxoplasmosis.