Medical Conditions and Diseases | PAWS Chicago

Medical Conditions and Diseases

Being aware of symptoms will help you treat your cat faster.


There are many diseases your cat can come into contact with.

Learning more about them will help you prevent them and recognize the signs so you can get your cat to a veterinarian to receive the treatment he needs quickly.

Common Conditions

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These tiny parasites are a common problem and can be transmitted from cat to cat. If your cat is scratching his ears or shaking his head, he may have ear mites. They look like brown spots, similar to coffee grounds, or clumps of dirt in their ears. Call your veterinarian for topical treatment.

Together, feline calicivirus and feline herpesvirus account for 80% to 90% of URIs. Sneezing, watery eyes, runny nose, fever and discharge from the nose or eyes are all symptoms of a URI.

Cats become infected by direct exposure to infected cats, either from sneeze droplets or from contaminated objects such as food and water dishes. Stressed cats have a compromised immune system and are more susceptible to URIs.

Most cats are exposed to these diseases at some point in their lives. If left untreated, they can be deadly, especially to kittens and senior cats. Cats with chronic herpesvirus signs can improve with excellent high-protein nutrition and Lysine supplementation. 

This is a disease of the lower urinary tract, affecting the bladder or urethra. About 5% of cats contract this infection. It’s not contagious. Symptoms include frequent trips to the litter box, crying, blood in the urine and straining to urinate. Changing to a moisture-appropriate diet (canned or frozen raw foods, not dry food) with high-quality protein can help improve the pH of the urine and prevent this condition. 

Serious Conditions

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Panleukopenia, also known as cat distemper, is a highly contagious and deadly viral disease. Symptoms include extreme listlessness and a loss of appetite. Fever, vomiting and diarrhea are frequently seen, but some cats die suddenly with few clinical signs. Kittens and unvaccinated cats are most susceptible to this disease.

This virus is shed in the feces or vomit of an infected cat and can survive extreme temperature and humidity. It is spread by exposure to the infected feces or vomit by sniffing or licking. Panleukopenia is part of the vaccine series recommended for all cats and provides excellent protection. Vaccinated adult animals are at minimal risk for this illness.

FeLV is a contagious, viral disease that suppresses the immune system. This makes a cat susceptible to infectious diseases and is a common cause of cancer.

It is shed in high quantities in saliva and nasal secretion, but also in urine, feces and milk from infected cats. Cat-to-cat transfer of the virus may occur from a bite wound or during mutual grooming. Transmission can also take place from an infected mother to her kittens, either before they are born or while they are nursing.

As kittens mature, they increase their resistance to FeLV. Nonetheless, even healthy adult cats can become infected.

There are two stages of FeLV:

  • Primary Viremia: During this early stage, some cats are able to mount an effective immune response and eliminate the virus from their bloodstream.
  • Secondary Viremia: This stage is characterized by a persistent infection of the bone marrow and other tissue. At this stage, a cat is infected for the rest of his life. The life expectancy for FeLV cats is two to three years after becoming infected.

To prevent a cat contracting FeLV, be sure his diet is high in protein, which supports a healthy immune system, and keep him away from any positive FeLV cats or cats of unknown FeLV status. The easiest method to do this is by keeping a cat indoors, or supervised when outside.

FIV is a disease very similar to human HIV/AIDS in that a cat can become infected with FIV and live many years until the disease progresses into feline AIDS. Cats with FIV have a compromised immune system and as a result, are vulnerable to other diseases. However, cats with FIV cannot transmit HIV in humans.

The primary mode of transmission for FIV is through bite wounds. It is not easily transmitted through casual, nonaggressive contact. As a result, cats in households with stable structures where housemates do not fight are at little or no risk for acquiring FIV. Infected cats can appear normal for years, but the infection eventually leads to a state of immune deficiency. An infected cat’s health may deteriorate progressively or be characterized by recurrent illness interspersed with periods of relative health. 

An FIV cat can live many months to many years with the disease, especially with an excellent high-protein diet and low environmental stress.

FIP is a disease caused by a corona virus. Many different strains of corona virus are capable of infecting cats, but most do not lead to FIP.

Most cats become infected by inhaling or ingesting the virus, either by direct contact with an infected cat, or by contact with a contaminated surface (clothing, bedding, toys, bowls, etc.). The virus can survive for a number of weeks in the environment.

nitial exposure to the FIP virus usually results in no obvious clinical disease, although cats may exhibit a mild upper respiratory disease or mild intestinal disease. Most cats who contract the primary infection completely recover, although some of them may become carriers. Only a small percentage (1% to 5%) of exposed cats develop the lethal disease, but it could be weeks, months or even years after becoming infected.

The major forms of FIP are:

  • Effusive (wet) FIP: This is characterized by the accumulation of fluid within the abdomen and/or chest. When fluid becomes excessive, the cat has difficulty breathing.
  • Noneffusive (dry) FIP: Fluid accumulation is minimal, although weight loss, depression, anemia and fever occur. Signs of kidney failure, liver failure, pancreatic disease, neurological disease or eye disease may be seen in various combinations.

Cats less than 2 years old, cats 10 years or older and cats who have an existing infection or are highly stressed are most susceptible.

FIP is difficult to diagnose because symptoms vary. Blood tests can detect the presence of virus antibodies, but a positive test result only means the cat has been exposed to the virus. A post-mortem tissue biopsy is the only way to confirm FIP. Once clinical signs appear, cats with effusive FIP will live a few days to a few weeks. Cats with noneffusive FIP can die within a few weeks, but could survive up to a year.

There is currently no cure or prevention for FIP other than providing a high-quality, high-protein diet to support a healthy immune system and decreasing environmental stressors.

Zoonotic Diseases

These diseases are transmitted between humans and cats. Transmission occurs by:

  • Saliva: Secretion from an infected cat
  • Feces: Excretion from an infected cat
  • Fleas or ticks from another animal
  • Food or water that has been contaminated by an infected cat

Most zoonotic diseases pose a minimal threat to people. However, individuals who have immature or weakened immune systems, including infants, individuals with AIDS, senior citizens and people undergoing cancer therapy, are more susceptible.

Cat-scratch disease is the most common zoonotic disease associated with cats. It occurs when a person is bitten or scratched by an infected cat. People with cat-scratch disease will usually have swollen lymph nodes and may experience fever, headache, fatigue, poor appetite, and sore muscles and joints. Healthy people generally recover with no lasting effects.

People usually contract Salmonella by eating contaminated food such as undercooked chicken or eggs. However, cats and other animals can carry and pass Salmonella bacteria in their stool. Salmonella can cause diarrhea, fever and stomach pain beginning one to three days after being infected. It usually resolves on its own. Wearing gloves and washing hands thoroughly after cleaning litter boxes can prevent human infection.

Fleas are the most common external parasite infection for cats. While fleas cannot thrive on humans, their bites can cause itching and inflammation. Cats may become infected with tapeworms when they ingest fleas while grooming. Checking their feces for worms and proper flea treatment (especially if there is a dog in the house) is essential.

Cats become infected with roundworms when they consume infected worm eggs from soil (generally through normal grooming), nurse from an infected mother or consume prey (usually a rodent) who is carrying developing worms. Anti-parasitic medications for kittens and annual fecal exams for adult cats can reduce environmental contamination and the risk of human infection.

Cat ringworm is a fungal infection that appears as a dry, scaly patch on human or cat skin. In most cases, a cat contracts ringworm from soil that is brought into the home by a human’s shoe. Ringworm is transmitted to humans by contact with the infected animal’s skin or fur. Infected cats drop fungal spores from their skin and fur that can cause infection for months and are difficult to get rid of. To reduce the spread of ringworm, keep the animal confined to one room until they are free from the infection. Then thoroughly clean and disinfect the household. On average, a cat is not clear of the fungus for 2-3 months or until they test negative with a culture done at your veterinarian. Most cats will be bathed in a medicated dip and receive oral medication to prevent the spread of the disease. Always wear gloves and change your clothing after you have contact with an animal infected with ringworm. 

These infections can cause diarrhea in both cats and people. Cats and people are usually infected by a common source—not from each other—such as contaminated water in the home that the cat and human are both drinking

Cats commonly become infected with toxoplasmosis by eating infected rodents, birds or anything contaminated with feces from another infected cat. An infected cat can shed the parasite in its feces for up to two weeks. It takes one to five days for the parasite to become capable of causing infection. But it can persist in the environment for months and will continue to contaminate soil, water, gardens, sandboxes or anyplace infected cats have defecated.

People with weakened immune systems or infants whose mothers are infected during pregnancy can develop toxoplasmosis. Proper hygiene can prevent it. Humans should wear gloves when handling potentially contaminated material and wash hands before and after. Sandboxes should be covered when not in use to prevent wandering cats from playing in them. Pregnant women and immunosuppressed individuals are safest when the other household members clean the litter box.

Rabies is a viral disease that results from the bite of an infected animal. Rabies attacks the central nervous system and is almost always fatal. In humans, a rabies infection is a result of being bitten by an infected animal such as a bat, raccoon or a stray animal. Rabies is a public health concern and your animals should be vaccinated. Be sure to check your city’s or state law to understand the policy on rabies vaccinations.