This disease is caused by the protozoan Toxoplasma gondii. Cats
are likely to acquire the infection by consuming infected birds or rodents or,
rarely, by ingesting oocysts in contaminated soil. Cats are the primary host
for this obligate intracellular parasite (a parasite that can only exist inside
the living cell of another organism), but it can infect other warm-blooded
Evidence strongly suggests that cats (and people) can also get the disease
from eating raw or undercooked pork, beef, mutton, or veal or unpasteurized
dairy products that contains toxoplasma organisms. In cats, the oocysts develop
in the intestines and are passed out in the feces, so the feces of infected
cats present another source of infection. These infective oocysts are only
passed for a very short time after initial exposure. Cats and humans can
transmit toxoplasma in utero to their unborn offspring.
The most common behavior problem reported by pet parents of cats is inappropriate elimination. It’s estimated that 10% of all cats will eliminate outside their litter box at some point in their lives. Quite a few of these cats have issues with some characteristic of their litter box (please see our article on Litter Box Problems for more information on litter box problems), but approximately 30% don’t have litter box problems at all. These cats are urine marking, and urine marking isn’t a litter...
Feline intestinal toxoplasmosis is usually
asymptomatic. When symptomatic, it affects the brain, spinal cord, eyes,
lymphatic system, and lungs. The most common signs are loss of appetite,
lethargy, cough, and rapid breathing. Visual and
neurological signs may be evident. Other signs are fever, weight loss, diarrhea, and swelling of the
abdomen. Lymph nodes may enlarge. Kittens may exhibit encephalitis, liver
insufficiency, or pneumonia. Prenatal infection
may be responsible for abortion, stillbirths, and unexplained perinatal deaths,
including the fading kitten syndrome. Many cats that show clinical signs are
concurrently infected with feline immunodeficiency virus
(FIV) or feline leukemia virus (FeLV).
Treatment: Antibiotics such as clindamycin
are available to treat active infection and prevent the intestinal phase of
Public health considerations: About half the human adult population shows
serological evidence of having been exposed in the past. Men and women with
protective antibodies probably will be immune to infection. However, the
disease is a particular hazard when a pregnant woman without prior immunity is
exposed to it. Immunocompromised people are also at risk.
Toxoplasmosis infection in a pregnant woman can result in abortion,
stillbirth, and birth of babies with central nervous system infection. Cats are
the only animals who pass on the infectious stage of this parasite through
their feces, and this has given rise to the incorrect assumption that pregnant
women should not have cats. If you are pregnant, it is not necessary to get rid
of your cat! The majority of human cases-by a wide margin-come from eating raw
or undercooked meat, particularly lamb or pork. Unpasteurized dairy products
can also be a source of infection. Wash fresh vegetables carefully, because
oocysts can also cling to bits of soil. And wear gloves while gardening to
avoid contact with infected soil.
It is important to understand the mode of transmission from cats to
understand how minimal the risk is. Even a cat with an active toxoplasmosis
infection is only capable of passing it on for seven to ten days of her entire
life, when there’s an acute infection. It takes anywhere from one to three days
for oocysts shed in the feces to become infectious-which means the litter box
would have to sit unscooped for one to three days before the infection could be
passed on. Then, to become infected from cat feces, a person would have to
touch the feces and then touch an opening in their body.