8 deadly cat diseases


Kelsey CruzBlog author Kelsey CruzKelsey Cruz is a feminist blogger from the city of brotherly love who is obsessed with bourbon, black blazers, and blow-out bars. She loves to cook and is always up to swap smoothie recipes. Mostly, though, she likes long walks on the Philly streets with her pit-boxer Henry of whom she will definitely show you pictures. Follow her on Twitter @kelsey_cruz.

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Updated September 21, 2020: Pets are important members of our families, and they make our lives whole. Since they make us happy and healthy, it is especially heartbreaking when they are sick and in pain because we can feel helpless to make them feel better. Cats make up approximately thirty to thirty-seven percent of the pets in American households, and since more than thirty-five percent of cats are acquired as strays (with an estimated 70 million living as strays in the U.S.), it’s imperative we protect our domesticated cats from disease.

One of the best ways to protect yourself financially from big veterinarian bills is by getting pet insurance. Learn more about pet insurance here.

These are some of the most prevalent cat diseases. Since cats can catch these eight illnesses from other cats in your house, on the street, or in the shelter, it’s important to keep an eye on them and take them to the vet if they start exhibiting any odd symptoms or behavior.

Here are some basic ways to tell if your cat is sick.

Kidney disease

Symptoms: dry coat, weight loss, bad breath, drooling, increased urination and thirst

While kidney disease can affect all cats of age and breed, it is especially found in cats seven years of age and older and long-haired breeds like Persians and Angoras. Acute renal failure can also occur if your cat ingests a toxic substance like antifreeze, pesticides, or human medications like ibuprofen.

"What heart disease is for humans, kidney disease is for felines – a leading cause of suffering and death," says Dr. Roberta Relford, chief medical officer of IDEXX Laboratories. "As they get older, the likelihood they will develop kidney disease increases."

If you suspect your cat has kidney disease, take her to the vet immediately so she can get blood and urine tests. If the kidney damage is due to a urinary-tract blockage, she will be admitted for surgery so the blockage can be removed, but if it’s due to obstruction, she will be given hydration therapy, medication, and kidney-friendly diets to treat the disease over time. The best way to treat kidney disease is to catch it early. Dr. Relford says SDMA, a test that screens for kidney disease, is available to all vets in U.S. and Canada and can detect kidney disease months to years earlier than if you wait to see until she’s old or until you see symptoms.

Kidney disease can be expensive to treat, especially if you don't have pet insurance. Here's what to do.

Feline immunodeficiency virus (FIV)

Symptoms: weight loss, dry coat, skin disease, diarrhea

FIV (related to HIV, but species specific to felines) is transferred by bite wounds, and once it enters the bloodstream and attacks the immune system, it is fatal. What’s more, FIV is classified as a lentivirus, or "slow virus," so infected cats can look normal for years as the virus slowly weakens his immune system. Although most vets check for FIV when your cat is a kitten, most FIV tests taper off as your cat grows older so you should request a checkup annually, especially if he’s exhibiting signs of the disease. To prevent your feline from contracting FIV, keep him indoors away from territorial and feral cats and keep him up-to-date on vaccines.

If you think your cat has FIV, take him to the vet so an antibody test can be administered to know for sure. If he does have FIV, he should be confined indoors so he cannot spread it to other cats or animals, spayed if he isn’t already, fed a healthy diet, and frequently taken to the vet for checkups. Although thoughts on specific life expectancy and how to handle a FIV-infected cat vary from vet to vet, most vets agree FIV does harshly impact and shorten a cat’s life.


Symptoms: increased urination and thirst, weight loss, vomiting, plantigrade stance (when your cat walks on her rear hocks instead of her toes)

Both types of diabetes are common in cats and appear to be on the rise because cats are living longer, are more likely to be obese, and eat high carb diets. Type 1 is less common and occurs when there is a lack of insulin while type 2 is more common and occurs when there is a resistance to insulin. Although there are two different types of diabetes, treatment is generally the same.

To determine if your cat has high levels of glucose, and, ultimately, diabetes, your vet will run urine and blood tests. If your cat has diabetes, she will need to have insulin injections twice daily and her diet and weight will be heavily monitored. To keep her on a healthy track over time and hopefully get her into a diabetic remission, take her regularly to the vet for checkups, monitor her blood and urine at home, and get her on a high protein/low carb diet.

If you aren't sure if your pet is healthy or not, here are some ways to tell.


Symptoms: diarrhea, skin disease, bladder infection, infertility

Leukemia is cancer of the white blood cells, and is spread through a virus found in saliva and urine. Cats that are the greatest risk of contracting it are those who live with or come in close contact with infected cats — cats transfer the virus via shared bowls or fighting or even the mother’s placenta.

To determine if your cat has leukemia, a virus test will be administered depending on which stage of infection you’re dealing with. Sadly, leukemia is often fatal in cats. Even cats with forms of leukemia that do respond to chemotherapy have an average survival rate of less than a year. Because there is no cure, the best way to keep your cat from contracting leukemia is by maintaining regular vet visits, getting her vaccinated, and keeping her away from infected cats and animals.


Symptoms: fever, weight loss, hyperactivity, aggression, muscle spasms, drooling

Rabies is a viral infection that is spread by a bite or saliva from an infected animal, and once the virus enters the body, it attacks your cat’s nerves, spinal cord, and brain and is fatal. Because of its severity and because it’s spread easily from animals to humans, many cities, states, vets, and groomers require cats to be vaccinated.

And if you thought rabies primarily affected dogs, you’d be wrong. In fact, according to the Centers for Disease Control and Prevention (CDC), cats are more likely to be reported rabid: "Cats are often in close contact with both humans and wild animals, including those that primarily transmit rabies."

Unfortunately, there is no treatment for cats once they contract rabies, and it is fatal. The best way to prevent it is getting her vaccinated and keeping her from rabid wildlife.

Feline Infectious Peritonitis (FIP)

Symptoms: weight loss, lethargy, fever

FIP is a disease caused by a feline coronavirus (FCoV) and is transmitted through feces. FIP has two forms – wet and dry. The wet form causes buildup in the chest, resulting in abdominal distension or respiratory problems. The dry form creates inflammatory lesions called pyogranulomas throughout the body, affecting vital organs and systems like the kidneys, liver, and nervous system. FIP primarily affects young cats under the age of two and is often fatal.

Unfortunately, preventing your cat from contracting FIP and even diagnosing him is difficult due to limited research and study. There are no screen tests to verify infection, and although a vaccination is available, it is not recommended due to its limited evidence of success.. Until more studies are conducted, the only treatment for FIP is palliative care, helping your cat feel as normal and comfortable as possible until euthanasia is chosen.


Symptoms: coughing, vomiting, weight loss, seizures

Heartworm is a dangerous and sometimes fatal disease that infects your cat’s heart and lungs. It’s spread by mosquitoes and has been reported in all fifty states, regardless of weather and climate.

The American Heartworm Society says heartworms are harder to detect in cats than in dogs (in fact, sometimes the first sign of heartworm in cats is sudden collapse or death). Cats should be screened, tested, and prescribed preventative medicine in order to thwart a heartworm infection. Unfortunately, unlike dogs, there is no drug used to treat heartworm infection in cats, so a long-term plan of proper vet care and maintaining monthly preventatives (like pills, topicals, or shots) is key. You can order popular heartworm treatments on sites like Chewy.com.


Symptoms: vomiting, diarrhea, increased urination and thirst, dry coat, change in appetite, heart disease

Hyperthyroidism comes from an overproduction of thyroid hormones, increasing the metabolic rate of your cat’s body and putting stress on her kidneys, heart, liver, and other vital organs. If left untreated, it can be fatal.

To find out if your cat has hyperthyroidism, your vet will conduct a physical exam, checking for enlarged glands and checking her heart rate and blood pressure. If she does have the disease, you have three options on how you want to treat it: medication, surgery, or radioactive-iodine therapy. While medication like anti-thyroid drugs and surgery are important treatments, radioactive-iodine therapy is quickly becoming the most popular form because of its low risk, high success, and lack of side effects.

Keeping pets healthy

Dr. Denise Petryk, DVM and in-house veterinarian for Trupanion, says although some health issues and diseases are out of your control, the best way to keep your cat healthy is by seeing your vet at least once a year for a regular checkup, requesting routine blood and urine testing after he’s seven years old, discussing nutrition with your vet and keeping an eye on your cat’s diet and weight, and keeping him active.

Learn more about how to keep all those checkup costs low here.

By keeping your cat inside and away from unknown feral cats and maintaining regular vet visits and a healthy diet, you’ll reduce his chances of getting sick, making the most of his nine lives.

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Blog author Kelsey Cruz

Kelsey Cruz is a feminist blogger from the city of brotherly love who is obsessed with bourbon, black blazers, and blow-out bars. She loves to cook and is always up to swap smoothie recipes. Mostly, though, she likes long walks on the Philly streets with her pit-boxer Henry of whom she will definitely show you pictures. Follow her on Twitter @kelsey_cruz.

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