There is a complete site map at the bottom of this page
This disease (caused by a parasitic organism) can cause serious birth defects in affected animals (and women).
It can also cause significant muscular aches and pains and more importantly, severe damage to the eyes, brain, and neural system.
This disease, normally contacted from eating under cooked meat and vegetables is a major problem in Asia, India, and Africa.
Cats are an important part of the problem but having a pet cat is NOT a major danger to pregnant women. We explain.
Toxoplasmosis disease gets a lot of press because of the terrible harm it can do to human fetus' of pregnant women who contact the disease during their 2nd trimester of pregnancy.
Women can get this disease by coming into contact with cats or microscopic amounts of cat feces ... so pregnant women are understandably anxious about cats. But there's a lot of misconception about this disease and people who hate and avoid cats are just as likely to be exposed to toxoplasma organisms as people who adore these fascinating creatures. So having a pet cat is not the problem.
That's because most people get exposed ... about 30% of the U.S. population have antibodies indicating exposure... by eating meat, grains, and vegetables that are contaminated with tiny, tiny, microscopic toxoplasma oocysts (eggs) that originally came from the feces of feral cats. Relatively few cases of exposure are from direct contact with house cats. The illustration below does an excellent job of explaining the routes of exposure.
The rest of this page is divided into two parts:
Part One: About the disease in cats and dogs
Part Two: About the disease in humans ... especially pregnant women.
Part One: The Disease in Cats and Dogs
Most cats and dogs show no clinical signs when infected with Toxoplasma. Or when first exposed to the disease, they may feel lousy and feverish for a day or two, but not only do they successfully fight off the disease but they also gain immunity to future infestation and disease.
This is true for most people too. But as you can see from the pie chart below, not all pets (or people) are so fortunate.
Note; dogs and other animals can and do get sick when exposed to toxoplasmosis but this is mainly a disease of cats.
On This Page:
Toxoplasomosis: about the disease in cats and dogs
Cardiology Heart disease in Cats, Cardiac Hypertrophy, Valvular disease, Cardiac Insufficiency, Congestive Heart Failure, Heartworm Disease, and a little history about the milestones in treating heart disease
Cats: general information page and directory of diseases and problems specific to cats including vaccine recommendations, leukemia, feline viral infections, feline upper respiratory disease and cats that just aren't feeling well.
The picture above is from a retinal scan... something we do routinely in our practice because being able to see the blood vessels tells us a lot about the general health of our patient. In the case above, we can see the damage (the bright area in the center of the picture) due to toxoplasmosis
But sometimes ... especially in kittens and young cats, toxoplasmosis can cause lethargy, depression, loss of appetite, and fever.
And respiratory distress that gradually gets worse is common.
Other pets occasionally experience liver disease, vomiting, diarrhea, pancreatitis, and lymph node swelling. (Most pets respond well to treatment, but since we don't routinely test for toxoplasmosis, I wonder how many cases of diarrhea and flare ups of liver disease or pancreatitis were due to exposure to this organism?)
Other pets, either due to bad luck, poor general health, suppressed immune systems, or because of excessive exposure can get very sick indeed. If the organism gets into the eye or nervous system this often leads to retinal and eye inflammation, blindness, personality changes, head pressing, ear twitching, seizures, paralysis, and trouble chewing and swallowing.
Since having a healthy immune system is one of the most important factors in whether or not your pet has mild versus serious disease when and if exposed to toxoplasmosis, let me remind you of all the common things that suppress or weaken immunity. These include:
- poor nutrition
- chronic illness and sometimes acute illness
- certain medications... especially steroids
- chronic stress
- immune suppressive diseases like leukemia and AIDS
We don't have a simple, accurate test for toxoplasmosis that veterinarians can do in their clinic.
Once we become suspicious of this disease, we have to send blood to a commercial lab for titers.
If the titer is low or negative in a sick cat, that reliably means that toxoplasmosis is not the cause of the sickness.
If the titer is high in a sick cat, that might mean the cat has a toxoplasmosis problem ... or not ...
We sometimes do titers for toxoplasmosis on healthy cats who live in a household with a pregnant woman.
The presence of significant antibody levels in a healthy cat suggests that the cat has been previously infected and now is immune and not excreting oocysts and therefore NOT a danger to the woman.
The absence of antibody in a healthy cat suggests that the cat is susceptible to infection and thus would shed oocysts for one to two weeks following exposure and could be a danger to pregnant women. But not only would the cat just happen to be exposed at the right time, but the organism would have to be successful at getting around your cat's immune system, and the woman, for her developing fetus to be at risk, would have to accidently ingest microscopic amounts of cat feces during her second trimester. This can, in fact, happen but luckily not too often. We'll discuss the details of prevention a little later.
So, the information we gain from testing your cat is helpful but not only are the results of the test a little vague but the test is fairly expensive (around $100). That's why testing is not commonly done (unless your pet ...dog or cat ... is exhibiting neural signs.
Treatment and Prevention
Outdoor cats are more at risk and cats fed raw meat diets are at high risk.
There isn't a vaccine for this disease.
There isn't a preventive medication available like there is for heartworm prevention and the control of intestinal parasites.
There isn't a specific treatment either. Treatment involves treating symptoms, antibiotics, and supportive care. And luck. The majority of pets without neural disease recover and do well... but not always. The prognosis for pets with neural signs is poor.
Part Two: The Disease in Humans
This disease gets a lot of attention in magazines for women since it can cause birth defects in the fetus if women are exposed to the disease during the second trimester of their pregnancy.
Note that this is a problem only if the woman isn't already immune to the disease from previous exposure (apparently, about a third of Americans already have immunity. Your physician can test for this if he or she thinks it worthwhile. And as I describe above, we can test your cat to help us determine, but not prove, whether or not your cat is a possible danger or not.
One of the ways people can get exposed to this disease is by accidentally ingesting microscopic amounts of cat feces. That is why women gleefully inform their husbands that they should be the ones cleaning out the litter box. But you could get microscopic amounts of fecal material on your hands just from petting your cat... afterall they clean themselves after defecating, and then use their tongues to groom their coat.
But don't get rid of your cat. Should you happen to get exposed and infested with toxoplasma organisms during your dangerous 2nd trimester, it's much, much more likely that the exposure was from some source other than your cat: eating unwashed vegetables, rare meats, gardening or otherwise exposing yourself to dirt where feral cats may have contaminated.
Prevention consists of avoiding rare meat (especially in the third world) and washing your hands and vegetables well.
Also, prevent cross contamination from raw meat to your vegetables from using the same cutting board etc.
And yes, limit your exposure to your cat and the litter box during mid pregnancy.
MAJOR NOTE: If your cat IS shedding toxoplasma oocysts (eggs), these oocysts DO NOT sporulate (become infective) for at least 24 hours. SO you can eliminate exposure to yourself by having someone clean the litter box DAILY. Good to know.
Symptoms in people:
Most infected people have no signs or symptoms. Those who do might have flu-like symptoms, swollen lymph glands, or muscle aches and pains that last for a few days to several weeks.
But our saddest risk is that human infants who are infected before birth often have serious mental or physical damage and defects.
But, people with weakened immune systems can develop severe toxoplasmosis, which results in damage to the eye or the brain. People might have have weakened immune systems for the same reasons as pets (There's a list above in the pet section).
This is probably why people in undeveloped countries, where malnutrition, parasitism, lack of sanitary facilities, and so forth are much more likely to suffer from the more serious forms of the disease. Or it may be because the feral cat population is not as well controlled and there are overwhelming numbers of organisms that people are exposed to. Or more likely both. Egypt seems to have an especially high incidence of cats that actively shed oocysts.
Politically correct Note: I probably shouldn't use the word "undeveloped" countries because many countries where diseases related to toxoplasma are prevelant are quite advanced; The Czech and Slovak Republics, Brazil, Costa Rica, and Brazil.
This is a scene of feral cats taken in Istanbul, one of the largest and most interesting cities in the world. But where ever there are overwhelming amounts of garbage there will be huge rodent populations... and large feral cat population. Garbage-rodent-feral cat control is a major challange for any large population area. The picture below is from India. The picture below that is from our own country... kind of... New Orleans after Mardi Gras.
Here's a very interesting study regarding toxoplasmosis:
Caution: I'm not sure about how accurate this information will turn out to be: Science involves alot of probing into ideas and theories that seem productive or true, but after looking at the evidence carefully (research and then more research to confirm), it turns out to be only somewhat true, or occassionally true, or a total red herring. If you're an adult, you will be used to all kinds of scientific pronouncements ...especially if politics are involved... (environmental issues come to mind) claiming one thing or another only to find out that conclusions were based on very skimpy, politically twisted, or faulty data.
None the less, I found this interesting:
Source: Veterinary Economic Magazine Nov 03 issue
Paraphrase: Scientists from Britian, US, and the Czech Republic say that Toxoplasma gondii, transmitted by cats, may have behavioral side effects for humans.
The Stanley Research Medical Institute of Maryland indicates that people infected with Toxoplasma are more likely to develop schizophrenia and manic depression.
Czech researcher Jaroslav Flegr, professor of Charles University in Prague claims that men infected with Toxoplasmosis MAY become more aggressive, antisocial, and appear scruffy and less attractive. Women, on the other hand, may become less trustworthy, seem more fun loving, and become more promiscuous. (Whoa...that's some scientific conclusion)
Also interesting: about 40% of adults in Britian and the US have titers for Toxoplasmosis indicating that they have been previously infected with the organism. The numbers are about double for adults in Germany and France.
(I'm thinking of getting a government grant to go study this in France and Germany.)
The main resevoir of toxoplasma organisms are feral cats. And one of the major reasons the feral cat population is so out of control is because of the rodent problem throughout the world whereever there are dense human populations and overwhelming garbage.
The following is from the U.S. Center for Disease Control
Recommendations for Pregnant Women:
Exclude rare or undercooked
meat and unpasteurized
Test household cats for antibodies to Toxoplasma. Assuming that a cat is healthy, a positive antibody test indicates that your cat is immune and not excreting oocysts and thus would be an unlikely source of infection.
A healthy antibody-negative cat is most probably susceptible to infection and would shed oocysts for one to two weeks after exposure to Toxoplasma.
Have herself tested for antibodies, preferably before becoming pregnant. A positive test would indicate past infection that will not be transmitted to the fetus.
The presence of antibodies also lessens the likelihood that congenital transmission would occur should she be exposed again to the parasite during pregnancy.
An antibody-negative woman would thus be at greater risk of transmitting Toxoplasma to the fetus should she become infected during pregnancy.
Protect cats from infection (or reinfection) by preventing access to birds, rodents, uncooked meat, and unpasteurized dairy products.
Avoid handling litter boxes. Even if a cat is antibody-positive and hence most likely immune, there exists a potential for reshedding of oocysts (although in much smaller numbers than during the initial infection). For safety, litter boxes should be changed daily or every other day by another person to eliminate any potential for accidental infection.
Avoid handling free-roaming cats, because the fur or paws could be contaminated with oocysts, which might be transmitted by hand-to-mouth contact.
Any cat allowed indoors should be kept off the bed, pillows, blankets, or other furnishings the woman uses.
Avoid handling any cat showing signs of illness.
Wear rubber gloves if working with garden soil. Uncooked vegetables, whether grown in a home garden or supplied commercially, should be washed thoroughly before ingestion, in case they have been contaminated by cat feces.
Make a habit of vigorously and thoroughly washing hands with soap and water after contact with soil, cats, unpasteurized dairy products, or uncooked meat or vegetables.
The picture above is of Cairo, Egypt, one of the filthiest cities in the world. It's not surprising that toxoplasmosis is a major disease problem in this country.