Can Cat-to-Cat Contagion Spread Illness?


Cats can bring immense joy and companionship into our lives. However, many cat owners have lingering concerns about the potential health risks cats may pose, especially if they have other pets or family members with compromised immune systems.

It’s important to understand how cats spread illnesses to each other and what preventative steps cat owners can take. While the risk of disease transmission exists, educated cat owners can greatly minimize it with proper precautions.

In this article, we’ll explore how cats pass illnesses between each other, identify common feline diseases, provide tips to prevent transmission, and outline how to care for a sick cat. Our goal is to empower cat owners with the knowledge needed to promote health and wellbeing for all pets in their household.

Common Illnesses in Cats

Cats can suffer from a variety of contagious illnesses that can spread between cats or even be transmitted from cats to humans. Some of the most common contagious cat diseases include:

Upper respiratory infections – These are very common in cats and can be caused by viruses, bacteria or fungi. Some examples include feline herpesvirus, calicivirus, Chlamydophila felis and Mycoplasma felis. Upper respiratory infections cause symptoms like sneezing, runny nose, eye discharge and fever. These illnesses spread through direct contact, aerosol transmission when an infected cat sneezes or coughs, or from contaminated surfaces. [1]

Feline leukemia virus (FeLV) – This is a retrovirus that weakens the immune system and predisposes cats to other diseases. It spreads through close contact, mutual grooming, bite wounds and shared litter boxes or food bowls. Symptoms can include lethargy, fever, loss of appetite and more. There is no cure, so prevention through vaccination is important. [2]

Feline immunodeficiency virus (FIV) – Similar to HIV in humans, FIV attacks the immune system, leaving cats vulnerable to other infections. It spreads through bite wounds, so outdoor and free-roaming cats are most at risk. There is no cure or vaccine, so keeping cats indoors reduces risk. Symptoms can take years to appear. [3]

How Cats Spread Illness

Cats spread illness through several methods including direct contact, shared items, and airborne transmission.

Direct contact with an infected cat, such as mutual grooming, allows infectious agents to transfer between cats. Diseases like ringworm, a fungal skin infection, can spread through direct contact with lesions or fungal spores on the coat. Respiratory illnesses like feline calicivirus are also transmitted by close contact between cats.

Using shared resources like food bowls, water bowls, and litterboxes can allow diseases to spread between cats in a household. Diseases like feline panleukopenia virus can survive in the environment and be passed through shared items. Parasites like roundworms and protozoa can also contaminate shared food and water sources.

Some feline illnesses can be transmitted through the air by sneezing, coughing, or even just breathing. Upper respiratory infections like feline herpesvirus and bordetella are easily spread between cats through respiratory droplets and aerosolized particles in the air. Keeping shared airspace clean is important to prevent airborne transmission.

According to the Cornell Feline Health Center, zoonotic diseases like cryptosporidiosis can also be transmitted from cats to humans through contact with infected feces.

Preventing Illness Transmission

There are several key steps cat owners can take to help prevent the spread of contagious illnesses between cats in the same home:

Keep cats up-to-date on vaccines. Vaccines help prevent many common feline illnesses such as panleukopenia, calicivirus, rhinotracheitis, and rabies. Following the vaccination schedule recommended by your veterinarian can help protect all household cats from dangerous diseases (

Isolate sick cats. If one cat is showing signs of illness like sneezing, coughing, or diarrhea, isolate it from other household cats right away. Keep the sick cat confined to one room so it cannot spread germs to other cats, and be sure to wash hands thoroughly after interacting with the isolated cat (

Disinfect shared items. Clean food and water bowls, litter boxes, bedding, toys, grooming tools, and any other items used by multiple cats regularly. Use a pet-safe disinfectant to kill illness-causing germs and prevent disease transmission between cats (

Spotting Signs of Illness

There are a few key signs and symptoms to watch out for to determine if your cat may be sick:

Sneezing, coughing [1]

Sneezing and coughing are common indicators of upper respiratory infections in cats. Persistent sneezing, runny nose, watery eyes, and coughing may signal your cat has caught an illness from another cat.

Lethargy, fever [2]

If your normally active cat suddenly becomes lethargic and lifeless, it could be a sign of illness. Taking your cat’s temperature and finding it is higher than the normal range (100.5-102.5°F) may indicate fever and infection.

Loss of appetite [3]

A decreased appetite or refusal to eat are common symptoms with feline illnesses. Any noticeable change in your cat’s regular eating habits could signal an underlying health issue.

When to See the Vet

If your cat displays persistent symptoms of illness for more than 24-48 hours without improvement, it’s time to schedule a veterinary appointment. According to the ASPCA, you should seek veterinary care if your cat has prolonged symptoms like lethargy, reduced appetite, vomiting, diarrhea, coughing, sneezing, eye/nose discharge or skin problems.

One of the most concerning symptoms is if your cat stops eating or drinking for an extended period. Cats can develop a dangerous condition called hepatic lipidosis, or fatty liver disease, if they go too long without food. According to VCA Hospitals, you should contact your vet if your cat hasn’t eaten for more than 24 hours. Lack of appetite and dehydration quickly becomes an emergency.

Make sure to monitor all symptoms closely, especially after introducing new cats into the home. Look for changes in behavior, activity levels, eating habits, bowel movements and appearance of coat. When multiple cats fall ill around the same time, infectious disease is likely spreading between them. Don’t delay in seeking veterinary help to protect your cat’s health.

Treating Contagious Illnesses

If a cat is diagnosed with a contagious illness, vets will often prescribe medications to treat the infection and reduce transmission. Antibiotics like doxycycline and amoxicillin are commonly used to treat bacterial illnesses in cats like bartonellosis and plague (Source). Antivirals may be prescribed for viral infections like FIV and feline herpesvirus. Vets may also recommend fluids and nutritional support if the cat is dehydrated or not eating due to illness.

Treatment depends on the specific illness, but antibiotics, antivirals, fluids, and nutritional support are often part of the protocol for cats with contagious diseases. The vet will tailor the treatment plan based on the cat’s symptoms, medical history, and diagnostic test results. Proper treatment can help sick cats recover more quickly while also reducing the risk of spreading the illness to other pets.

Caring for a Sick Cat

When a cat is sick, it’s important to properly care for them to help aid in their recovery. Here are some tips for caring for a sick cat:

Isolate the sick cat from other pets. Keep the sick cat confined to one room or area of the home to prevent spreading illness to other pets. Be sure to wash hands and change clothes after interacting with the sick cat before tending to healthy pets. Refrain from introducing any new pets to the household until the sick cat has fully recovered.[1]

Monitor the sick cat’s appetite and litter box use. Make note of any changes in food or water intake as well as urination and defecation. Loss of appetite, diarrhea, constipation, straining, blood, or other abnormalities should be reported to the veterinarian.[2]

Keep stress low for the sick cat. Make the isolation space comfortable with familiar toys, bedding, litter box, food and water dishes. Give the cat affection if interested, but don’t force interactions. Playing calming music, using pheromone diffusers, or providing other enrichment can help reduce stress.[2]

With proper care and veterinary guidance, most cats can make a full recovery from illness. Be vigilant in monitoring the sick cat and alert the vet to any concerns.

Preventing Reinfection

Once a cat has fully recovered from a contagious illness, it’s important to take steps to prevent reinfection and spreading illness to other pets. The key is allowing full recovery before mixing cats together again.

Veterinarians typically recommend keeping a cat isolated from other pets for at least 2 weeks after symptoms have fully resolved. This gives the cat’s immune system time to clear the infection and reduces the risk of recurrence or spreading the illness to other pets in the home. Some vets may recommend an even longer isolation period depending on the specific illness.

It’s also crucial to fully disinfect the home after a contagious illness outbreak. Use a veterinarian-recommended disinfectant and thoroughly clean any surfaces the sick cat had contact with. This includes food bowls, litter boxes, bedding, floors, countertops, and any shared items. Maintaining good hygiene practices like hand washing is also important to prevent reinfection.

By allowing proper isolation and recovery time as well as disinfecting the home environment, cat owners can help prevent contagious illnesses from repeatedly spreading between their pets.


In summary, cats can pass illnesses to each other through direct contact, shared litter boxes, fleas, and other vectors. Some of the most concerning contagious cat diseases include panleukopenia, calicivirus, rhinotracheitis, and ringworm. Preventing illness transmission involves keeping cats up to date on vaccines, maintaining good hygiene, and separating sick cats. Watch for symptoms like fever, lethargy, sneezing, coughing, and skin lesions, which can indicate contagious illness. Seek prompt veterinary care for suspected contagious diseases to get proper treatment and stop the spread. With vigilance, prevention, and early intervention, cat owners can keep their feline companions happy and healthy.

Scroll to Top