Cat Diseases: 8 Common Illnesses and Their Warning Signs
Cat diseases are health conditions, mostly viral, bacterial or metabolic, that range from mild sneezing to life-threatening illness. Every cat owner benefits from knowing the early signs, because cats hide pain well and vaccines prevent several of the deadliest infections.
This post may contain affiliate links. As an Amazon Associate I earn from qualifying purchases.
Table of Contents
Cat diseases at a glance:
- Short Answer: The most common cat diseases are upper respiratory infections, urinary tract disease, FeLV, FIV, FIP, panleukopenia, diabetes and rabies.
- Most Common Causes: Viruses spread by saliva, urine, feces and bites, plus bacteria, obesity and age-related organ changes.
- Urgency: Straining to urinate, labored breathing and refusing food for 24 hours or more need a vet the same day.
- What to Do at Home: Keep the litter box clean, track appetite and water intake, and isolate sick cats from healthy ones.
- When to See a Vet: Any lasting change in appetite, energy, weight or bathroom habits.
The Most Common Cat Diseases
Most serious cat diseases are caused by viruses, and many can be prevented with a vaccination schedule that starts in kittenhood. Here are the eight conditions vets see most often.
1. Upper Respiratory Infections
Upper respiratory infections are the most common cat disease in shelters and multi-cat homes, usually caused by feline herpesvirus and calicivirus. Signs include sneezing, nasal discharge, watery eyes, fever and lost appetite. Mild cases need supportive care, while bacterial complications may need fluids and antibiotics prescribed by your vet.
2. Feline Lower Urinary Tract Disease
Feline lower urinary tract disease affects the bladder and urethra and causes frequent trips to the box, straining, crying and blood in the urine. Stress, crystals and stones are common triggers. A male cat who strains and passes no urine is an emergency because the urethra may be blocked. A spotless litter box helps you notice changes quickly, and our guide to blood in cat urine explains what to watch for.
3. Feline Leukemia Virus (FeLV)
FeLV is a retrovirus that weakens the immune system and can cause cancers such as lymphoma. It spreads through saliva, bite wounds, shared bowls and from mother to kittens. Signs include weight loss, anemia, enlarged lymph nodes and recurring infections. Young kittens and cats in feral colonies are most at risk, and vaccination is the best protection.
4. Feline Immunodeficiency Virus (FIV)
FIV spreads mainly through deep bite wounds, so outdoor, unneutered males are most affected. The virus slowly damages immune cells, and many infected cats live for years with good care. Read more about FIV in cats and its treatment options.
5. Feline Infectious Peritonitis (FIP)
FIP is caused by a mutated coronavirus and is most common in kittens and young cats from crowded environments. Signs include fever, poor appetite and a swollen belly from fluid buildup. Historically fatal, FIP now has treatment options in some countries, so ask your vet what is available locally.
6. Feline Panleukopenia
Panleukopenia, also called feline distemper, is a parvovirus that attacks fast-growing cells and causes fever, vomiting, diarrhea and dehydration. Kittens are hit hardest, and the disease can be fatal within days. Vaccination is highly effective, and sick cats should be separated from healthy ones immediately.
7. Diabetes
Diabetes is common in overweight and middle-aged to senior cats. The classic signs are excessive thirst, frequent urination and weight loss despite a good appetite. Many cats are managed with diet and cat insulin therapy under veterinary supervision. Our diabetes in cats guide covers monitoring in detail.
8. Rabies
Rabies is a deadly viral disease spread through the bite of an infected animal, and it can infect humans. Vaccination has made it rare in many regions, but it remains a risk for unvaccinated cats that go outdoors. Any suspected exposure needs immediate veterinary and medical attention.
Signs of Cat Diseases to Watch For
Cats instinctively mask illness, so small behavior changes are often the first and only warning. Check your cat for these signals every day.
- Eating or drinking noticeably more or less than normal
- Weight loss or a swollen belly
- Vomiting or diarrhea lasting more than 24 hours, as covered in cat vomiting and diarrhea
- Persistent coughing, wheezing or open-mouth breathing, as in coughing cats
- Hiding, unusual aggression or lethargy
- Lumps, sores that do not heal or bad breath, including the signs of tumors in cats
Common Diseases in Senior Cats
Cats over 10 years old are more prone to chronic kidney disease, hyperthyroidism, diabetes, arthritis, dental disease and cancer. These conditions develop slowly, so a drop in weight or a change in thirst is easy to miss. Twice-yearly vet exams with blood and urine tests catch problems months earlier. A basic Cat Health Supplies kit at home, including a digital thermometer made for pets, helps you report accurate details to your vet. Learn more about hypothyroid disease in cats and other age-related conditions.
Preventing Cat Diseases
Prevention is cheaper and safer than treatment, and it rests on a few reliable habits. Follow these steps for the best protection.
- Vaccinate kittens on schedule and keep adult boosters current, as outlined in cat vaccinations.
- Test new cats for FeLV and FIV before introducing them to resident cats.
- Keep cats indoors or supervised outdoors to avoid fights, wildlife and infected strays.
- Use vet-approved flea control, and discuss mosquito repellents that are safe for cats, since heartworm is spread by mosquitoes.
- Maintain a healthy weight to lower diabetes and urinary risks.
- Book a yearly checkup, and see regular veterinary check-ups for cats for what to expect.
When to See a Vet for Cat Diseases
Any cat that stops eating for 24 hours, strains in the litter box or breathes with effort should see a veterinarian promptly. Always contact a vet before giving any medication, and never give human medicine to cats, because many are toxic. Resources like the Cornell Feline Health Center offer reliable guidance on specific conditions.
Emergency signs include:
- Straining to urinate with little or no urine
- Open-mouth breathing or blue-tinged gums
- Repeated vomiting or bloody stool
- Collapse, seizures or sudden weakness in the back legs
Recommended products:
Frequently Asked Questions
What is the most common disease in cats?
Upper respiratory infections are the most common illness in cats, especially in shelters and multi-cat households. Dental disease and urinary problems also rank very high in veterinary visits.
Which cat diseases can be prevented with vaccines?
Vaccines protect against panleukopenia, feline herpesvirus, calicivirus, rabies and feline leukemia virus. Kittens usually start core vaccines at 6 to 8 weeks old, with boosters every few weeks until about 16 weeks.
Can cat diseases spread to humans?
Some can, but most feline viruses such as FeLV, FIV and FIP do not infect people. Rabies is the major exception, and ringworm and some parasites can also spread, so wash your hands after handling a sick cat.
How do I know if my cat is sick?
Look for changes in appetite, water intake, energy, weight and litter box habits that last longer than a day or two. Cats hide symptoms, so even a subtle shift deserves a vet call.
Knowing the common cat diseases, their early signs and the vaccines that prevent many of them gives your cat the best chance at a long life. Start today by checking your cat’s vaccination dates and booking a yearly vet exam.
