Things You Should Know
About Cats
Cats are capable of infecting humans with several diseases, but in general, cats are safe pets. By following good hygiene practices, you can protect yourself and your cat from disease.
Toxoplasmosis
Toxoplasmosis a disease caused by the parasite Toxoplasma gondii and humans can become infected in two ways: 1) ingestion of improperly cooked meat from animals serving as an intermediate host, and 2) the ingestion of infective particles from cat fecal contamination. Although human infection with T. gondii is widespread, certain immunocompromised individuals are more likely to have severe manifestations of the disease. It is likely that an individual has, at some time in his life, been exposed to this organism, and that any infection in an individual with HIV is actually a reactivation of a latent toxoplasmosis due to immune suppression. It is for that reason that blood tests are routinely performed on patients early in the course of HIV infection. Because T. gondii is ubiquitous, removing pet cats from "at risk" households may have little effect on the number of new cases of Toxoplasmosis seen with HIV disease. However, it is still very important to practice good hygiene habits and to prevent your uninfected cat from becoming infected.
What is Toxoplasmosis?
Toxoplasmosis is an infection caused by the parasite Toxoplasma gondii.
Who gets it?
All species of animals can become infected, including humans.
Why are cats blamed for Toxoplasmosis?
Cats are the only definitive hosts for Toxoplasmosis. This means they carry the sexually reproducing stages of the organism, and can shed actively infectious particles into their environment. However, any infected animal can disseminate Toxoplasmosis if their meat is eaten.
How do cats get it?
Cats can become infected by consuming other infected mammals, fish, birds, amphibians or reptiles, or by coming into contact with the infected feces of another cat.
How will I know if my cat has Toxoplasmosis?
You probably won't since most infected cats show no symptoms.
Should I worry about getting Toxoplasmosis from my pet cat?
You could acquire the infection from your cat and caution is advised for individuals who are immunocompromised.
Should I test my cat for Toxoplasmosis?
Probably not--test results in cats are questionable and interpretation controversial. In fact, a positive, healthy cat is probably safer than a negative cat since it has already been exposed and is immune. A negative, healthy cat is probably susceptible to infection, and thus prevention is most important.
How do I prevent my cat from getting it?
Don't feed your cat raw meat, prevent your cat from hunting and keep your cat indoors.
What happens if I get Toxoplasmosis?
It depends... If you are healthy--probably nothing; flu-like symptoms such as fever, malaise or lymph node enlargement and/or soreness may occur but will pass. If you have an immunocompromised system-- possibly life-threatening central nervous system disorders.
How do I know it I have been exposed to Toxopalsmosis?
Persons diagnosed with HIV are routinely tested for Toxoplasmosis. Consult with your physician.
Once infected, can I get it again?
After the first infection, it is very unlikely that you will get it again, because your immune system will develop a resistance to it. But if your immune system becomes suppressed, an old infection can become reactivated. Since 15-50% of the U.S. population (depending on where you live) has already been exposed, most cases of Toxoplasmosis in people with AIDS are a reactivation.
How can I prevent it?
To prevent Toxoplasmosis, always practice good hygiene. You should cook meats well and wash vegetables, wear gloves while gardening, and wash hands after handling raw meat or gardening. Keep your cat healthy will regular check-ups, and use caution around litter boxes.
Feline Leukemia Virus (FeLV) and Feline Immunodeficiency Virus (FIV)
Infections with these viruses are restricted to cats. Humans can not be infected with FeLV or FIV, nor can cats become infected with HIV. However, similar to HIV, these diseases do suppress the cat's immune system, making it more susceptible to other diseases that it could pass on to you. Even though it would be difficult to part with your cat, it is probably best not to keep a FeLV or FIV positive cat if you have an immunosuppression problem yourself. If you do keep your cat, be extra careful about following safe hygiene practices, and keep your cat indoors and as healthy as possible.
Cat Scratch Disease
Cat Scratch Disease is considered to be a treatable bacterial infection; the cats themselves do not appear to be ill. The disease is acquired from the scratch of a cat, hence the name, but it is not the same thing as a cat scratch that becomes secondarily infected. The causative organism is of uncertain identity. Some believe it is the organism Afipia felis, while others believe it is Rochalimaea henselae, but the role of these organisms in Cat Scratch disease has not yet been defined.
Cat Scratch appears to be most commonly acquired from kittens, and thus, declawing an older cat is unlikely to change the risk of disease. In general, this disease is still uncommon in persons with AIDS. The present recommendation is to keep your cat's nails trimmed monthly. If a cat scratches you, clean the wound with a tamed iodine solution such as Betadine, and call your physician for further advice. Do not let your cat lick any wounds you may have, as this is another way the disease appears to be spread. Declawing is an option you may consider, but this is more likely to prevent frayed furniture than Cat Scratch Disease.
About Fish
Be cautious around aquarium water. At risk people have been shown to acquire unusual infections from the water. Be especially careful if you have cuts or sores on your hands. Consider having someone else do your water changes and tank maintenance for you.
About Dogs
Dogs do carry some diseases that could be spread to humans. Follow good hygiene practices and keep your dog free from parasites. Do not let your dog drink from the toilet bowl, puddles, streams, etc.
About Birds
Birds can carry some diseases that are transmissible to people. However, they can be safe pets if you are careful. An avian veterinarian should check all new birds for potential health risks.
Mycobacterium avian-intracellulare Complex
In humans, this disease is identical to M. tuberculosis. The organisms are found in soil and water, as well as infected poultry, swine, and other animals. Although human exposure is common, significant human disease is rare, except in immunocompromised patients. Patients with AIDS are at particular risk. Infection is believed to be primarily by ingestion of contaminated food or water. Disease initiated by inhalation of the organism is less common, and person-to-person spread does not occur.
Psittacosis (parrot fever)
Psittacosis is caused by the bacteria Chlamydia psittaci. The natural reservoir of C. psittaci is birds; any species of birds, as well as humans can become infected. The organism is present in the blood, tissue, feces and feathers of infected birds, and transmission to humans is usually by inhalation of dried bird droppings; person-to-person transmission is rare. The infected bird may be ill appearing or completely asymptomatic. Prevention of psittacosis requires control of infections in domestic and imported birds.
Salmonella
Salmonella are found in virtually all animals, including humans. The source of most infections is ingestion of contaminated water or food products, or direct oral-fecal spread. The most commons sources of human infections are poultry, eggs, and dairy products. Although exposure to salmonella is frequent a large dose is required to cause illness, that dose is reduced for individuals who are immunocompromised.
Can Bird diseases make me sick?
Diseases such as Mycobacterium avian-intracellulare Complex, psittacosis (parrot fever), salmonella, and allergic alveolitis are the primary diseases associated with pet birds. There is some potential for transmission to humans.
Should I worry about acquiring infections from my bird?
There is less chance of acquiring an infection from a bird than from a mammal, although a bird actively shedding the agent may transmit the disease.
What are the chances that my bird has one of these infections?
That depends on many things: the species of bird, where it came from, age, and general health status may dictate the likelihood of carrying an infection. A veterinarian experienced in avian medicine should be consulted to evaluate your particular situation.
Should my bird be tested?
Yes. All newly acquired birds in the parrot family should be screened for psittacosis. Your veterinarian is better able to evaluate other diseases for which your bird should be screened.
How do I prevent my bird from getting these diseases?
Never expose your bird to other birds (including pigeons and other wild birds) that have not been tested and quarantined for 45 days. Avoid casual contact such as going to the pet store for wing clips and nail trims. Ideally, birds should be cared for at home, rather than in a boarding facility.
Who can acquire these diseases?
Individuals with compromised immune systems are at highest risk, but any individual with increased contact with birds could become infected.
How do I get these diseases?
These diseases are transmitted by direct contact with stool and nasal discharges, or inhalation of breathing dried droppings. Breathing feather dander is the cause of allergic alveolitis, if you are sensitive to bird protein.
Which avian species are most likely to cause or transmit these diseases?
Imported birds are most likely to carry M. avian. Cockatiels have the highest incidence of psittacosis. Regarding allergic alveolitis, any bird can transmit this disease; however, cockatoos, cockatiels, and amazons that produce more "powder" than other birds could potentially be more irritating.
How do I locate a veterinarian who has experience with birds?
Contact your state or local veterinary medical association, or contact the Association of Avian Veterinarians, P.O. Box 811720, Boca Raton, FL 33481, telephone: (407) 393-8901.
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