How many cat owners have toxoplasmosis?

Kansas State University

MANHATTAN — Toxoplasmosis is a disease that can have devastating effects on an unborn child, and many women have been erroneously advised to get rid of their cat if they are pregnant, says Susan Nelson, veterinarian and clinical professor at Kansas State University’s Veterinary Health Center.

«Toxoplasmosis is a devastating disease for some but with proper precautions, a woman does not need to rehome her cat if she becomes pregnant,» Nelson said.

Toxoplasmosis is a single-celled parasite known as Toxoplasma gondii. It is most commonly found in areas with hot, humid climates and situated in lower altitudes. More than 60 million people in the U.S. may be infected with the parasite and up to 95 percent of people in some areas of the world may be infected, according to the Centers for Disease Control and Prevention. Fortunately, most people with a healthy immune system will experience only mild symptoms if infected. The organism can cause serious health issues for those people who are pregnant or immunocompromised, Nelson said.

Although people can contract toxoplasmosis from cats, the most common ways to acquire the disease include eating and handling raw meat; drinking unpasteurized goat’s milk; eating and handling raw vegetables; drinking contaminated water; and gardening. Other less common modes are eating raw or undercooked oysters, mussels and clams.

Toxoplasmosis is most likely to be spread to an unborn child when the mother is infected just before becoming pregnant or during pregnancy. Even though a pregnant woman may not experience any symptoms, the disease can cause miscarriage of the fetus, a stillborn child or severe damage to the eyes and nervous system of the child, which may not develop until later in life. Women can be tested prior to pregnancy to see if they have already been exposed to toxoplasmosis, as transmission of the disease to an unborn child is uncommon in this situation.

Cats are the definitive host for the organism and they are infected by eating rodents, birds or other small animals that are infected with Toxoplasma. The oocysts that cats shed in their feces are capable of infecting people. Cats can shed millions of these microscopic oocysts for up to three weeks after they have been infected.

Treatment options are available for humans and cats with the disease.

Nelson offers the following safety precautions to minimize the risk of contracting toxoplasmosis:

• Ensure the cat litter box is changed daily. It takes one to five days after it is shed in a cat’s feces for the Toxoplasma parasite to become infective. If you are pregnant or immunocompromised, avoid changing cat litter if possible. If no one else can perform the task, wear disposable gloves and wash your hands with soap and water afterward.

• Keep cats indoors so they cannot hunt and eat rodents, birds and small animals.

• If pregnant, do not adopt or handle stray cats, especially kittens, as they are at a higher risk of shedding the organism. Do not get a new cat while you are pregnant as it may be shedding the organism at time of adoption.

• Feed cats only canned or dried commercial food or well-cooked table food, not raw or undercooked meats.

• Keep your outdoor sandboxes covered so cats cannot defecate in them.

• Make sure meats are cooked to recommended safe temperatures and freeze meats at subzero temperatures — 0 degrees Fahrenheit — for several days before cooking.

• Peel or wash fruits and vegetables thoroughly before eating, and do not eat raw or undercooked oysters, mussels or clams.

• Do not drink unpasteurized goat’s milk and do not feed this to cats as well.

• Wash cutting boards, dishes, counters, utensils and hands with hot soapy water after contact with raw meat, poultry, seafood, or unwashed fruits or vegetables.

• Wear gloves when gardening and during any contact with soil or sand that could be contaminated with cat feces that contain Toxoplasma. Remember to wash hands with soap and water after gardening or if they come in contact with soil or sand.

• Teach children the importance of washing hands to prevent infection.

Cat Toxoplasmosis Advice & Care

Toxoplasma is a type of protozoa – a microscopic, single-celled parasite – which can also infect humans.

Many of the toxoplasma parasites will stay within the intestines of the cat, but some can migrate deeper into the body. Usually this spread is controlled by the cat’s immune system, and the travelling parasites end up in a resting state in muscles and in the brain. These pockets of infection in the tissue can also form in other affected species, such as mice and birds, and these can then infect a cat who catches and eats these prey species. Toxoplasma’s ability to ‘hide’ from the immune system in these resting pockets, or cysts, mean that many affected animals are infected for life unless they are given treatment.

Most infected cats show no signs at all of infection. In cats with a poor immune system, however, who are not able to suppress these travelling parasites, toxoplasma may show as clinical signs. This clinical disease is known as toxoplasmosis.

Read more about toxoplasma in cats

How Can My Cat Get Toxoplasma?

Cats become infected through any contact with the toxoplasma parasite, including:

• Direct contact with infected cat faeces
• Contact with a contaminated environment, as infectious eggs can survive in soil for several months in the right conditions
• Eating infected prey, such as mice and birds
• Eating undercooked meat
• Kittens can be exposed to toxoplasma whilst in the womb

Toxoplasmosis Symptoms in Cats

Most cats do not show any signs of toxoplasma infection. Cats who are more likely to develop signs include kittens who are infected whilst in the womb and cats with suppressed immune systems, such as those with FIV or FeLV. In cats who do develop clinical disease, signs can include:

• High temperature
• Going off food
• Tiredness/lethargy
• Weight loss
• Fits or muscle tremors
• Loss of balance
• Muscle weakness
• Eye inflammation
• Shortness of breath
• Death, especially in new-born kittens

If your cat is experiencing any of these signs then make an appointment with your local Vets4Pets and get them checked out.

How Can I Stop My Cat Getting Toxoplasma?

There is no Preventive medicine or vaccine to stop your cat from picking up toxoplasma, but some simple strategies can reduce the risk:

• Keep it clean. Frequently cleaning and disinfecting your cat’s areas, especially toilet areas, will help keep toxoplasma at bay.
• Reduce hunting. Although preventing hunting can be difficult in outdoor cats, simple tricks like attaching a bell to their collar can reduce the amount of predation – and supports local wildlife too!
• Cooked not raw. Don’t feed your cat raw meat, as this may contain pockets of toxoplasma.
• Cover outdoor sandpits. Cats love to toilet in sandpits, and toxoplasma levels can rise in areas frequented by lots of cats for toileting purposes.
• Empty it regularly. Toxoplasma eggs in cat poo need several days to become infectious. Keeping the litter emptied frequently will prevent any eggs that are present from infecting any other pets or people.

Toxoplasma treatment in cats

Most cats that have toxoplasmosis can recover with treatment using an appropriate antibiotic. If a cat is severely unwell, they may need more supportive care as well, which may include hospitalisation and being placed on a drip. Treatment should be started as soon as possible after diagnosis to get the most rapid recovery.

What About My Health?

It is estimated that 500 million people worldwide have been infected by toxoplasma. In the UK it is thought that 20-30% of the UK population may have antibodies (markers in the blood which show exposure to a specific infection) to toxoplasma in their blood. Many infected humans have no signs, or just mild flu-like symptoms, but toxoplasmosis can be severe in babies and young children, the elderly, and people with a supressed immune system, such as those with AIDS or after organ transplants.

Despite the high numbers of people who appear to come across toxoplasma in their lives, it is thought relatively few of these exposures are from infected cats. This is because:

• Cats only have infectious faeces for less than two weeks
• Indoor cats that are not fed raw meat are unlikely to have toxoplasma
• Cats do not carry the parasite on their fur, so stroking your cat is unlikely to result in exposure
• Infection cannot be passed via bites or scratches
• Eggs in cat faeces take several days to become infectious, so regular litter tray cleaning means it is likely most eggs in cat faeces in the home will not lead to infection.

The more common routes of infection of people are:

• Eating raw meat
• Eating unwashed fruit and vegetables
• Drinking unpasteurised milk
• Contact with contaminated soil
• Infection in the womb, if the mother gets toxoplasma whilst pregnant.

It is this final route of infection that is most heavily seen in the media – it is for this reason that pregnant women are advised not to empty cat litter trays. While it is important to take normal hygiene precautions when handling cats, it should be noted that studies have shown that having a cat, or working with cats, causes little or no increase to your risk of contracting toxoplasma. If you think you may have been exposed to toxoplasma, and are concerned, always contact your doctor for advice.

What Should I Do If I Think My Cat Has Toxoplasma?

If you think your cat might have a toxoplasma infection, the best thing to do is to go to your vet. They can do a full physical examination, and check your cat over from nose to tail.

To diagnose toxoplasma your vet may recommend laboratory tests, as well as looking at the clinical signs and taking a full history from you about your cat. These tests may look for the toxoplasma eggs themselves, which are invisible to the human eye, but as cats only shed these in their faeces for up to two weeks after an infection, this can miss cases. Blood tests can also be used to look for antibodies (markers in the blood which show exposure to a specific infection), which can suggest either an old or a new infection, although this is not 100% accurate. Taking tissue samples can provide a definite diagnosis, but this is invasive and may not be recommended.

If your cat does test positive for toxoplasma, this actually reduces the risk of you catching toxoplasma from them! Infected cats are infectious for less than two weeks, and are then very unlikely to shed infectious eggs in their poo again. This means cats that test positive are rarely an infection risk to other pets or their owners.

Cats who are negative for toxoplasma can be at a higher risk, as there is no way of knowing if or when they will become infected and start producing infectious faeces.