Family doctor

Overview:

• Toxoplasmosis is an infection carried by cats
• It causes no harm to the general population
• It can be fatal and cause birth defects if a mother passes it to an unborn child
• The infection can cause brain and eye damage in people with weak immune systems
• A blood test can confirm contact with toxoplasmosis
• The disease can reactivate in AIDS patients who need to take drugs to prevent this

What is it?

Toxoplasmosis is a common infection that is found in many animals and birds, and is carried by cats.

The infection normally causes no harm. However, it can cause birth defects if an infected mother passes it to the unborn fetus, particularly in the first three months of pregnancy.

It is spread through handling cat litter, anything else that has been in contact with cat feces, or from eating raw or undercooked meat. It can also be spread through organ transplants, however, this is rare.

The disease affects the eyes, heart, lungs and central nervous system in unborn children.

The infection is also serious in people with weak immune systems such as AIDS patients.

Cats can only spread the parasite in the first few weeks after they have been infected. Since cats rarely show signs of infection, it is hard to know whether they have the parasite.

What are the symptoms?

Toxoplasmosis can be passed to an unborn child through an infected mother, causing birth defects.

The infection is often fatal. If the infant survives it may be disabled, mentally retarded and blind.

About 80 percent of people who are infected do not have symptoms, but those who do may have flu-like symptoms such as fever and aches and pains. The incubation period is between one and two weeks.

The disease can reactivate in AIDS patients, causing brain and eye damage.

Blood tests can confirm exposure to toxoplasmosis.

What can be done to help?

Most people do not need treatment because the infection usually disappears by itself.

Those who need drug treatment include infants, people with weak immune systems and those whose eyes are affected.

Pregnant women who are infected during the first three months of pregnancy should consider termination of the fetus. Fetuses whose mothers were infected six months before pregnancy are not at risk of birth defects.

The benefits of routine screening of all women are controversial.

How can it be prevented?

Healthy people do no need to worry about avoiding infection because it very rarely causes problems.

Those with weak immune systems and pregnant women who have not been infected before need to take precautions to avoid infection. These include:

• Wearing gloves while gardening and handling soil or sandpits
• Washing your hands well after gardening and handling soil
• Wearing gloves when handling raw meat
• Cooking all meat until there is no pink in the middle
• Do not give your cat raw meat to eat, just canned food or cat biscuits
• Avoid handling kittens
• Do not bring a new cat into the home
• Wear gloves when handling cat litter trays

AIDS patients and others with weak immune systems who have acquired toxoplasmosis in the past may need to take medication to stop it from reactivating.

Getting help

Your doctor, maternity carer, or obstetrician will be able to help.