Diseases Contracted from Cats

Diseases Humans Can Contract from Cats

by Margaret Schill

Contracting diseases from cats, especially from stray cats, is a fear of some people. Below are some alarmist exaggerations spread by people not well educated about cats and diseases, and statements often used to try to discourage kindly cat minded folks from getting involved with homeless cats.

You'll catch a disease! You'll get rabies! They'll give you toxoplasmosis! All your house cats will die from illnesses from them! You'll get worms!

Stray cats are considered a nuisance by many people, so it's preferable for some to ascribe dramatic, terrible things to the stray cats, to make ignoring their sad plight, chasing them off, and even killing them, easier on the conscience and justified. A deluded sort of "self defense". But it's NOT justified. With common sense, simple precautions, information and knowing your limits, the above dire "pronouncements" will not happen. If more people knew the truth, more stray cats would be saved, since it is often the poor cats on the street who get the diseases, worms, infected bites and scratches and then die alone, in pain, forgotten.

Read on for information about Rabies, Cat Scratch Fever (Bartonellosis), Toxoplasmosis, and Ringworm.

There are different "categories" of stray cats, ranging from lost tame pet cats to extremely feral cats. There are various diseases and parasites cats can get. Regardless of whether a cat is a tame pet, or a truly wild feral cat, there are few diseases that cats can pass onto humans, and only then in very rare, select circumstances which does not include the cat just sitting there. People can get some parasites from cats in rare situations, but with proper hygiene, a person will not get a parasite from a cat. Any scared animal will bite and scratch. But if one doesn't touch the animal or corner it and then put a body part near it, one cannot get bit or scratched. So, the mere presence of stray cats in your yard, or on your porch poses no risk or threat to any person.

Just as there are different categories of stray cats, there are different levels of interacting with stray cats and different levels of risks for each level.

At the “lowest” level, simply setting out a bowl of food on your porch, you will not contract any sort of illness or injury from the stray cats who come to eat.

Even if you are sitting on your porch while the cats are eating, you risk no harm to yourself. There is no disease you can get from a cat breathing or even sneezing in the same area you are in. You cannot get any disease or illness simply being near an area where a cat urinated or defecated. You will not get fleas from being near a stray cat, as fleas will not hurl themselves off their current host onto a human hoping to find a bare patch of unclothed skin (though indoors, unless a cat with fleas is promptly treated, fleas will eventually infest your carpets and then you might get bitten by fleas.) You cannot get infected bites or scratches if you don’t try to touch the cat. Stray cats do not lunge at people to attack them, unless they feel threatened by a person coming into their personal space, are cornered and trying to escape, or sometimes to protect their kittens. If you don’t corner a cat or try to touch it, it won’t try to bite or scratch you.

There is a lot of "bad press" about feral cats and supposed dangers and health hazards they may present. True feral cats are cats born and raised in the wild who never had contact with humans, aside from perhaps looking at people. Think of them as "hardcore" ferals. Those cats can be dangerous to handle as they are basically wild animals. But, unless you trap one, or manage to corner one, you likely will only see a flash of fur as they race away in fear when you come near. So without any contact, no danger to any person at all.

People commonly encounter tame homeless cats, who had been pets. Some people are reluctant to try to befriend and take in friendly strays due to misunderstandings or concerns about diseases. The information below will hopefully put to rest the common fears about possible contraction of diseases from cats.

Cats are subject to cat specific diseases, and can catch serious illnesses from each other. To protect one's current house cats from possible diseases from a stray cat newly taken in, one needs to keep them totally separate until a vet has examined, tested for FIV (Feline Immunodeficiency Virus), FeLV (Feline Leukemia), checked for parasites, and given the ok to allow mingling of the new cat with the resident cats. Keeping current pet cats up to date on vaccines will also offer some protection (but not total) from some of the diseases contagious between cats.

For general information on cat diseases, see:


(Disclaimer: This article is not written by a veterinarian or medical doctor. Always contact appropriate personnel for any medical problems or questions you may have.)


Rabies is a big scare because it can be deadly. But is has been sensationalized as to the true risks of contracting it. It is a viral infection of the central nervous system. To contract rabies, the saliva of the infected animal must get into your body. That would be by a bite of a rabid animal, or by a rabid animal licking an open wound on your body. You cannot get rabies from touching the fur of a rabid animal. But don't do that if you feel the animal has rabies, or it might turn and bite you! Rabies is treatable if medical attention is received promptly. And, even if bitten by a rabid animal, the person bitten does not always contract rabies, especially if the wound is immediately washed thoroughly with soap and water for several minutes.

According to Joe Bodewes, DVM (http://www.purinaone.com under "Cat Care"):

"It has been speculated that only around 15 % of exposed people will contract the disease. Humans, cats, and dogs are only mildly susceptible to the disease unlike skunks, raccoons, foxes, and bats that are much more susceptible to the virus."

The National Center for Infectious Diseases http://www.cdc.gov, under Questions and Answers About Rabies) says:

"One of the most effective methods to decrease the chances for infection involves thorough washing of the wound with soap and water."

It is not very likely that a cat would have rabies. According to the National Center for Infectious Diseases, under "What Happens if a Neighborhood dog or cat bites me?",

"rabies is uncommon in dogs, cats, and ferrets in the United States. Very few bites by these animals carry a risk of rabies. ... Other contact, such as petting a rabid animal or contact with the blood, urine or feces (e.g., guano) of a rabid animal, does not constitute an exposure and is not an indication forprophylaxis.

In the United States, raccoons and skunks are the biggest carriers. From 1980 to August 1997, only 34 cases of human rabies have been documented in the United States, and none from cats (there was one case from an unknown animal). http://www.emedicine.com/emerg/topic493.htm Over 17 years with millions of stray cats all across America and only 34 cases of rabies in humans, not even due to cats. If rabies from stray cats was such a danger, there'd be a whole lot more cases of rabies in humans considering how many people have been taking in strays and how many millions of stray cats have been handled by shelter workers over the years. Cats certainly can have rabies of course, so one does need to practice common sense in handling or not handling unknown cats. But the dramatic warnings some people give about "getting rabies from stray cats" as if it's practically a done deal is just that. Drama.

Still, one should not try to pet and certainly not pick up and hold a stray cat who had not made overtures or body signals indicating acceptance of being handled. Not so much due to rabies, but just getting bit or scratched period. A very friendly, perky, healthy looking cat, mewing or purring while rubbing in a friendly manner against your legs, is really not going to be a rabid cat about to bite you. So if some cat like that comes your way, do not hesitate to try to help it and find out if it does have worried owners looking for it. One can pick up tame cats in such a way as to avoid being bitten, but do be aware that cats can get scared easily. So, limit handling of tame seeming cats until you get to know them better.

Symptoms of Rabies in Cats: Cats can show signs of rabies in about 7 days after contracting it from a bite from a rabid animal. The only way to test an animal for rabies is for it to be killed and have it's brain examined. But, cats can be kept on "rabies watch" for 10 days to see if they have rabies based on any symptoms. According to the Harford County, MD Department of Health, (http://www.co.ha.md.us/health/EC/rabies.htm)

"As long as the animal remains healthy for that period, no risk of rabies transmission exists. If the animal develops signs of rabies or dies during the period, it must be submitted rabies examination."

Symptoms vary as well as being different during the three stages of the rabies virus. Some animals seem to only have two stages. Details can be found here: http://www.peteducation.com/article.cfm?cls=1&cat=1316&articleid=346. In brief, at first a cat may have a fever and frequently lick the site of the bite for a day or so. Next, in the "furious form", the cat may be very agitated, lose all caution and fear, and be hypersensitive to noise and visual stimuli, including light. There is often aggressive and erratic behavior. The cat may then move on to seizures, then death. Some cats go on to the paralytic, "dumb", third stage, which causes increasing paralysis of the facial muscles, resulting in drooling or foaming at the mouth. Staggering and difficulty walking with the hind legs is sometimes noted. The cat may seem unusually tame along with some other signs. The animal weakens, stops breathing, then dies. This stage usually develops 2-4 days after the first signs of rabies are observed.

Never touch a stray animal that appears sick, is drooling, is moving in an uncoordinated manner, or acting in a strange way! They can be handled safely by people wearing thick gloves and with good knowledge and experience with handling sick or injured cats. If you are not experienced in handling possibly fractious cats, best to call someone for help. The animal may not have rabies, but an animal in pain may lash out when handled. Pre-rabies exposure shots are available for people, so those working with stray cats may be interested in discussing that with their physicians.

Links with information about rabies:


http://www.cdc.gov under Health and Safety Topics- Diseases and Conditions-Animal Related Diseases-Browse by Disease-Rabies-Rabies Site


http://www.purinaone.com(under Cat Care)




Cat Scratch Fever (Bartonellosis)

Also called Cat Scratch Disease, Bartonellosis, or Bartonella,(and not to be confused with Hemobartonellosis*), it is a usually benign, self limiting illness that most often requires no treatment, though it can be very serious in individuals with compromised immune systems. It is actually not very common. One estimate by the Centers for Disease Control found that there were 2.5 cases of CSD per 100,000 people per year in the United States. However, since there are often very mild to no symptoms, or people consider their symptoms to be a "cold", those people would not have been tested for it. People rarely get it more than one time. It does not require being scratched by a cat to get it. People also get "cat scratch disease" from scratches from dogs, squirrels, barbed wire, and thorny plants, etc. Cat bites can spread it as can licks by cats on open wounds. Declawing cats (amputation of the toes up to the first joint) is not a method of avoiding Bartonellosis. Some people who are found to have it have no known scratch or bite from any animal to account for a way they acquired it.

(*Hemobartonellosis is also called Feline Infectious Anemia and is caused by a different parasite than Bartonella/Cat Scratch Disease)

Cat Scratch Fever is believed to be caused by the bacteria Bartonella henselae.The bacteria is in the cat's blood, but not in all cats. It is believed cats get infected from fleas carrying the bacteria, and possibly ticks. The theory as to how it gets on the claws of cats is the bacteria gets into the cats' saliva, which then gets onto their claws when they groom. Kittens are most commonly associated with it. It is believed that cats develop immunity to the bacteria, which accounts for it rarely being transmitted by older cats. Infected cats can transmit Bartonella to other cats through scratches, bites, licking, sneezing and hissing or spitting in the face of the other cat. Cats can carry the bacteria in their blood for many months, but at some point it is no longer present. Cat Scratch Fever tends to occur more in the fall and winter, and in areas with greater flea populations. Symptoms in cats: Some internet sources, including web pages of veterinary offices, say cats don't show any symptoms from Bartonellosis, but that is not true. Cats can develop a high fever for two or three days, gingivitis, bronchitis, pneumonia, conjunctivitis (eye infection), anemia and lymph node swelling from Bartonella. There can be some neurological involvement and infection of certain organs. According to Ron Hines, DVM at http://www.2ndchance.info/catscratch.htm "It appears that a few cats that contract bartonellosis show mild loss of sensation in their paws, lack of balance and disorientation that resolves within a few days. At the microscopic level, there is evidence that the organism attacks the liver, kidney, spleen and lining of the heart. But damage to these organs is usually temporary and without symptoms." Some cats may only show one or two of the symptoms and some cats might not show any of them, at least not that cat owners were aware of, as some mild symptoms may go unnoticed..

Cats can also have mild symptoms that seem to resolve on their own in two or three days, that their humans don't feel warrant a vet visit, so the cat is never taken to the vet. Since many symptoms of Bartonellosis are also symptoms of other illnesses, or bacterial or viral infections from other causes, many vets don't consider Bartonellosis, but rather treat the symptoms with a diagnosis of "some type" of bacterial or viral infection. Testing is needed to determine if a cat is infected with Bartonella henselae, and many vets don't see the need or practicality to do special testing to determine which virus or bacteria may be causing an illness or symptom, since there are hundreds of different bacteria and viruses and one might never find which exact bacteria or virus is responsible for the symptoms. One also would need to have an idea of what to test for.

However, a dark red gum line can be a signal that a cat has Bartonellosis, so cats with that, especially along with some other symptom, should be tested for Bartonella. Vets may just diagnose a cat with dark red gums as having a "general" gingivitis, but Bartonella may be the cause of more cases of gingivitis and stomatitis than is currently considered. A study done in 1997 by Guptill L, Slater L, Wu CC, Lin TL, Glickman LT, Welch DF, HogenEsch, H. at Perdue University found a statistical correlation between stomatitis and the presence of antibodies to Bartonella henselae, as well as renal and urinary tract abnormalities. (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&list_uids=9207369&dopt=Abstract)

Cats can be tested for Bartonella by a polymerase chain reaction test, blood culture, or serologic testing. The treatments for cats for Bartonella are the antibiotics Zithromax, doxycycline, tetracycline, erythromycin, amoxicillin-clavulanate, or enrofloxacin.

Case study:

A young cat I fostered who had been found in a wooded park, came to me feeling warmer than cats usually do, but his initial vet checkup proclaimed him healthy, with him testing negative for FIV (feline immunodeficiency virus) and negative for FeLV (feline leukemia virus). Lungs and heart sounded good. About a week later, the cat started panting during very vigorous play with an interactive streamer toy, whereas he had not done so the first few days of the same type of play. I had heard him sneeze few very times, maybe once a day, (though I was out of the house for many hours each day) not seeming to necessarily be part of an illness.

One of my other cats, who had been kept physically separated from the new cat, but allowed a few seconds per day of peeping at the new cat through a door crackedopened, and also allowed in the room the new cat had been in, with the new cat put in a different room at that time, developed some very infrequent sneezing about two weeks after the cat arrived. About two weeks after that, a month after the new cat arrived, the resident cat developed a high fever of 104 degrees, and was, needless to say, extremely lethargic the whole day, not having the strength to get up to eat, drink or use the litter box, but did use the box when carried to it and would drink a little from water droplets placed on his tongue. He was examined, some congestion heard in his lungs, and diagnosed with an upper respiratory illness, and given a course of antibiotics. After a few days, he was acting like his former, energetic self.

About that same time, a month of being in our home, the new cat developed a very deep, though infrequent, cough. Upon exam, he was found to have a sore throat, enlarged lymph glands, and the vet could hear wheezing in his lungs. But no fever. He was diagnosed with a general upper respiratory illness and given the antibiotic Baytril. He seemed to be better after a few days, with no more coughing, but he continued to pant from active play, though it did take longer for the panting to start than it did prior to the antibiotic course. When that continued panting was discussed with the vet about a month later, without the cat present for exam, the vet was not concerned and said it was probably from the vigorous play. This didn't seem to be correct to me, as no cat out of the great many I ever had panted from running around or even from very strenuous interactive play,and the cat in question had not done so initially. Plus, when the new cat was brought to the vet with the panting noted, at that time the vet said it was not normal for cats to pant (and the new cat did have wheezing in his lungs to prove that the panting had a respiratory cause).

The cat went to his new home about three months after coming to me, where he still panted so was examined by his new vet. Though otherwise pronounced very healthy, with lungs clear, that vet noted the deep red line along the cat's gum line, and suspected Bartonella. The blood test came back a strong positive. The cat was prescribed three weeks of Zithromax. The cat did not have that deep red color along his gums when he was examined by my vet due to the coughing, but I did notice his gums looked red the day before he was set to go to his new home. Obviously, it was a later development in the course of the Bartonella infection.

Based on my experiences with the two cats, panting in a cat during play may well be a symptom of Bartonella, and it seems Bartonella can be spread to other cats via inhalation due to sneezing and hissing of infected cats. I do not know if my resident cat that came down with the mysterious high fever and minor sneezing had Bartonella, but it now seems that may well have been what it was.

Symptoms in humans: Some people don't really notice any symptoms, or may have a headache, fever and fatigue for a few days, which can be taken as being a cold or mild flu. In a person who had acquired Cat Scratch Fever, pustules (pimples) will often develop at the site of the scratch or bite 5-10 days after exposure. Sometimes it is considered to be a rash. The person may experience fever that can last up for one to two weeks, there may be a headache and lethargy, and swollen lymph nodes usually develop. Some people develop tonsillitis and neck pain along with the fever and lymph node swelling. Not all symptoms in occur in all people. If a rash (pimples) occurs, it may last one to four weeks. The lymph nodes tend to not swell until one to four weeks after the causative event, basically when the rash goes away. The lymph nodes may remain swollen for four to six weeks, but can remain swollen for many months. More severe cases can result more severe symptoms. It can become a very serious problem for immunosupressed individuals who need to consult with their physician if they develop symptoms, as the bacteria can infect various organs, such as the liver, spleen and even the heart, lungs and brain. People at great risk for serious symptoms are those who have had organ transplants, AIDS (Acquired Immunodeficiency Syndrone) and who are undergoing chemotherapy.

The majority of people do not require antibiotics or any special treatment and recover in two to three weeks. However, according to Dr. Hines, "Doxycycline, erythromycin and rifampin are the antibiotics of choice in humans but the course of the disease can also be shortened using azithromycin, ciprofloxacin, trimethoprim/ sulfamethoxazole, or clarithromycin." To determine if a person's symptoms are due to Bartonellosis, other diseases and illnesses need to be ruled out. There is a test for Bartonellosis, with a blood culture, culture from a lymph node or a polymerase chain reaction test.

When dealing with stray cats, one can avoid being scratched or bitten by not touching them, or only touching them after the cat has given clear signals that it is feeling friendly towards you and will be accepting of being touched (i.e. rubbing on you while purring). Washing any bite or scratch thoroughly and promptly can help avoid any type of infection. Immunosuppressed people need to take great care when thinking about touching stray cats. But they can certainly feed stray cats without fear of Cat Scratch Fever.

Links with information about Cat Scratch Fever:












Toxoplasmosis is another exaggerated disease with lots of misinformation being spread around- even by ob-gyns. Toxoplasmosis is caused by the parasite toxoplasma gondii. It gets into cats if they have eaten infected birds or rodents. Not all birds and rodents are infected. Not all cats eat birds and rodents. Therefore, not all cats carry the toxoplasmosis parasite. If a cat did eat an infected bird or rodent, the parasite then reproduces in the cat's intestines, and it's "eggs", called oocysts, are excreted in the cat's feces.

The only way possible to get toxoplasmosis from a cat is if you ingest infected cat feces. People don't normally do that intentionally, but people scooping litter boxes sometimes wind up with some fecal matter on their hands, then put their fingers in their mouths or eat food with their hands, without having washed their hands before doing those things. An easy way to avoid toxoplasmosis due to cat feces- wash your hands after scooping the litter box and before putting your fingers in your mouth or eating.

Cats do not remain infective forever if they did happen to get infected with toxoplama gondii. The oocysts are only spread for two or three weeks. It takes 24 to 48 hours for them to sporulate (turn into a form that can be infective to people). So in a house with pet cats, scooping the litter box promptly will avoid feces from becoming a problem. After the initial active infection, cats don't shed oocysts again because they produce antibodies against it.

People can also get toxoplasmosis from cat feces in their gardens. Some people pull weeds, or dig in the soil for some reason, then, do not wash their hands before putting their fingers in their mouths or eating with their hands. Same protection against toxoplasmosis from outdoor cat feces as with indoor cat feces- wash your hands after digging in the dirt and before putting your fingers in your mouth or eating. Wearing gardening gloves is always a good idea, as one would likely take them off before putting fingers in the mouth or eating.

People mostly acquire toxoplasmosis from eating undercooked meat. Nothing to do with cats. You cannot get toxoplasmosis from touching a cat. You cannot get toxoplasmosis from breathing in an area where there are cat feces. You cannot get toxoplasmosis from a cat having sprayed urine on your door, or even on you.You have to ingest the oocysts that might be in cat feces to get it due to cats. Pregnant women do not have to get rid of their cats. They should wear gloves when scooping litter boxes, though, in case they forget to wash their hands after scooping litter boxes.

Links about Toxoplasmosis:





Links with more information about zoonoses and diseases of cats:




Sleeping kitten healing from ringworm.
(photo courtesy of Alicia)

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