# Is Cat Pneumonia Contagious to Other Cats? Pneumonia in cats is it contagious? Sometimes. It depends on the cause. Pneumonia itself is not a single disease, it is lung inflammation with many possible triggers, and only the infectious causes can pass from cat to cat [1][2]. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - Viral and bacterial respiratory infections are the most common contagious causes of pneumonia in cats, and they spread mainly through sneezing, coughing, and shared bowls, bedding, or litter boxes [1][3]. - Aspiration pneumonia (from inhaling vomit, food, or medication) and allergic pneumonitis are not contagious to other cats [1][4]. - Most feline respiratory viruses do not infect dogs or people, but Bordetella bronchiseptica can pass between cats and dogs. - Keep a sick cat separated from other cats, wash your hands between cats, and do not share food bowls, water bowls, or litter scoops. - A cat with pneumonia needs veterinary care. Some causes are life threatening without treatment [2]. ## What Pneumonia Means in Plain Words Pneumonia is inflammation of the pulmonary parenchyma, which is the deep lung tissue made up of the small airways, the interstitium, and the alveoli (the tiny air sacs where oxygen enters the blood) [2]. When those air sacs fill with fluid, cells, or debris, breathing becomes hard work and oxygen levels in the blood can drop [1]. This is different from an upper respiratory infection, which mainly affects the nose, throat, and sinuses. An upper respiratory infection can be contagious on its own, and it can also spread downward into the lungs and set the stage for pneumonia [1]. That is why a simple runny nose in one cat can sometimes turn into something more serious in another. ## Signs Owners Notice Cats hide illness well, so early pneumonia can look like nothing more than a quiet, tired cat. Watch for: - Coughing, which may be soft and wet or dry and hacking - Fast, labored, or open-mouth breathing - Noisy breathing or a wheeze - Fever, lethargy, and hiding - Not eating or drinking - Weight loss over days to weeks - Nasal discharge, sneezing, or eye discharge if an upper respiratory infection is also present - A blue or gray tint to the gums or tongue in severe cases Coughing and sneezing often overlap in cats, and the pattern of symptoms can help your veterinarian narrow down the cause. If your cat is sneezing a lot with no other signs, that alone is usually not pneumonia. You can read more about that pattern in [Cat Sneezing a Lot: Allergies, Infection, or Something Else?](/knowledge/veterinary-medicine/vet-visit-decisions/cat-sneezing-a-lot). If the cough is dry and repetitive, see [Cat Is Dry Coughing](/knowledge/veterinary-medicine/symptom-guides/cat-is-dry-coughing). ## Causes and Risk Factors Pneumonia has many possible causes, and only some of them are contagious [1][2]. ### Contagious Causes The most common cause of pneumonia is a viral infection of the lower respiratory tract [1]. Feline calicivirus, for example, damages the airways and makes a cat more vulnerable to pneumonia [1]. Feline herpesvirus type 1 causes viral rhinotracheitis, pneumonia, and eye disease, and it spreads through direct or indirect contact with secretions from infected cats [3]. About 80 percent of infected cats establish lifelong latent infections, which means the virus can reactivate later during stress or illness [3]. Bacteria such as Mycoplasma and Chlamydia can also cause pneumonia [1]. In one study, Mycoplasma species were found in 28.3 percent of cats with rhinitis compared with 5.4 percent of healthy cats, and Mycoplasma felis was found in 21.7 percent of rhinitis cases but in none of the healthy controls [5]. Feline herpesvirus was also more common in cats with rhinitis (39.1 percent versus 8.1 percent), and herpesvirus detection was linked with Mycoplasma detection in that group [5]. Bordetella bronchiseptica is another respiratory pathogen that can be found in cats with rhinitis. ### Noncontagious Causes Aspiration pneumonia happens when a cat inhales vomit, food, or improperly administered medication. It can also occur in a newborn with a cleft palate [1]. This type cannot spread to another cat. Allergic pneumonitis is an allergic reaction in the lungs and small airways, often triggered by a parasite or another irritant. The lungs overreact and cause inflammation and a chronic cough [4]. It is not contagious. Fungal infections, lungworms, flukes, and protozoa such as Toxoplasma gondii can cause pneumonia in cats [1]. A case report described a cat with nodular pyogranulomatous pneumonia caused by Besnoitia darlingi, a protozoan never before reported in feline pneumonia [6]. These causes are generally not passed from cat to cat through normal contact. ### Risk Factors - Living in a multi-cat home, shelter, or cattery - Being very young, very old, or immunocompromised - Recent stress, boarding, or a new cat entering the home - Dental disease or a cleft palate that raises aspiration risk - Chronic herpesvirus infection that reactivates [3] ## Is Pneumonia in Cats Contagious to Other Cats, Dogs, or People? This is the question most owners ask first, and the answer depends on the underlying cause. | Cause of pneumonia | Contagious to other cats? | Contagious to dogs? | Contagious to people? | |---|---|---|---| | Feline herpesvirus (FHV-1) | Yes, through secretions [3] | No | No | | Feline calicivirus (FCV) | Yes | No | No | | Mycoplasma species | Likely, especially with close contact | Unclear | No | | Bordetella bronchiseptica | Yes | Yes, can pass between cats and dogs | Rarely, mainly a concern for immunocompromised people | | Chlamydia felis | Yes, between cats | No | No | | Aspiration pneumonia | No [1] | No | No | | Allergic pneumonitis | No [4] | No | No | | Fungal, parasitic, protozoal causes | Generally no | No | No | The practical takeaway: if your cat has pneumonia caused by a virus or bacteria, assume it can spread to other cats until your veterinarian says otherwise. If the cause is aspiration, allergy, or a noninfectious irritant, other cats are not at risk from the pneumonia itself. ## How Pneumonia Is Diagnosed Your veterinarian will start with a full history and a physical exam, listening to the lungs and checking breathing rate and effort. Diagnosis is based on history, clinical signs, thoracic radiographs (chest X-rays), and other laboratory testing [2]. Expect some combination of: - Chest X-rays to look for consolidation or inflammation in the lung lobes [2][6] - Blood work to check for infection, inflammation, and organ function - Airway sampling, such as a bronchoalveolar lavage, to collect cells, bacteria, or parasites from the lungs [4] - Fecal analysis and a heartworm test if lung parasites or heartworms are suspected [4] - PCR testing on nasal or airway swabs for viruses and bacteria such as Mycoplasma, herpesvirus, calicivirus, Bordetella, and Chlamydia [5] In one reported case, a cat with a month of chronic cough, difficulty breathing, and lethargy had consolidation of the right middle and caudal lung lobes on X-rays, and the cause was only identified after cytology, histology, and PCR testing [6]. That case shows why a single test is not always enough. ## Treatment Options Treatment depends on the cause, and it is supportive care plus targeted therapy when a specific agent is identified [2]. - Oxygen therapy for cats who are struggling to breathe [2] - Antimicrobial therapy when a bacterial cause is suspected or confirmed [2] - Antiviral medications for herpesvirus-related disease [3] - Nebulization, coupage, and keeping the nose clear to help cats move secretions - Appetite support, fluids, and a quiet, warm space to rest - Treating the underlying trigger for allergic pneumonitis, which may include parasite control [4] Your veterinarian calculates every medication dose from your cat's weight and health status. Never give a cat human cough medicine, human antibiotics, or leftover medication from another pet. ## Recovery, Outlook, and Long-Term Management Recovery depends on the cause, how sick the cat was at diagnosis, and how quickly treatment started. Cats with mild viral pneumonia often improve over one to two weeks with supportive care. Cats with severe pneumonia, especially those needing oxygen, may take longer and may need hospitalization. Some cats never fully clear herpesvirus. Roughly 80 percent of infected cats carry it for life, and it can reactivate during stress [3]. That means a cat who recovered from viral pneumonia may have flare-ups later, and those flare-ups can be contagious to other cats during active shedding [3]. Long-term management often includes: - Keeping stress low, since stress can trigger herpesvirus reactivation [3] - Routine veterinary checkups, especially if your cat has chronic respiratory signs - Good dental care, since dental disease and swallowing problems raise aspiration risk - Watching for early signs of relapse, such as more sneezing, coughing, or appetite loss ## Prevention in a Multi-Cat Home You cannot prevent every case of pneumonia, but you can lower the odds and slow the spread. - Vaccinate. Core vaccines reduce the severity of herpesvirus and calicivirus disease and help limit transmission [3]. - Isolate a sick cat. Keep the cat in a separate room with its own food bowl, water bowl, litter box, and toys. - Wash your hands between cats. Change clothes if a sick cat has been sneezing on you. - Do not share bowls or litter scoops between cats, even after the sick cat seems better. - Clean surfaces. Herpesvirus spreads through direct and indirect contact with secretions, so wipe down counters, carriers, and bedding [3]. - Quarantine new cats for at least two weeks before introductions. - Reduce crowding. Fewer cats in a small space means less stress and less close contact. - Treat underlying problems. Manage dental disease, vomiting, and any condition that raises aspiration risk [1]. If your cat has been sneezing and coughing together, that combination deserves a veterinary visit. You can read more about what those paired signs usually mean in [Cat Coughing Sneezing](/knowledge/veterinary-medicine/symptom-guides/cat-coughing-sneezing). ## Limitations and When to Contact a Veterinarian No article can tell you whether your specific cat has pneumonia or whether it is contagious. That requires an examination, and often X-rays and lab work. Your veterinarian sets the plan for your cat. Call your veterinarian the same day if your cat: - Is coughing more than a few times a day - Has nasal or eye discharge that is thick, yellow, or green - Is eating less than usual or losing weight - Has been sneezing for more than a few days - Lives with other cats and you are unsure whether to isolate Go to an emergency clinic now if your cat: - Breathes with the mouth open or with the elbows out - Has a breathing rate that stays high while resting - Has blue, gray, or pale gums - Collapses, cannot stand, or seems unaware of surroundings - Is gasping or making a loud, distressed noise while breathing Schedule a routine visit if your cat has a chronic cough, a history of herpesvirus, or repeated respiratory flare-ups, even when the current episode seems mild. ## Frequently Asked Questions ### Can my other cats get pneumonia from my sick cat? They can catch the infection that caused the pneumonia, not the pneumonia itself. Viral and bacterial respiratory infections spread through sneezing, coughing, and shared items, so a second cat can develop the same infection and, in some cases, pneumonia too [1][3]. Keep the cats separated and ask your veterinarian how long to continue isolation. ### How long should I isolate a cat with a respiratory infection? There is no single number that fits every case. The right duration depends on the cause, how long your cat sheds the organism, and how well the other cats are protected. Your veterinarian will set the isolation period for your cat based on the diagnosis and your home situation. ### Can my dog catch a respiratory infection from my cat? Most feline respiratory viruses do not infect dogs. Bordetella bronchiseptica is the main exception, since it can be found in cats with respiratory disease and can pass between cats and dogs [5]. If your cat has a confirmed Bordetella infection, keep it away from dogs until your veterinarian clears it. ### Is cat pneumonia contagious to people? Feline herpesvirus, calicivirus, and Chlamydia felis do not infect people. Bordetella bronchiseptica is rarely a concern for healthy people but can matter for immunocompromised individuals [5]. Practice good hand hygiene and ask your veterinarian if anyone in your home has a weakened immune system. ### Can a cat get pneumonia again after recovering? Yes, especially if the cause was herpesvirus. About 80 percent of infected cats carry the virus for life, and it can reactivate during stress or illness [3]. A reactivation can cause respiratory signs again and can be contagious to other cats during active shedding [3]. Routine checkups and stress reduction help lower the chance of a repeat episode. ## Related Articles - [Cat Sneezing a Lot: Allergies, Infection, or Something Else?](/knowledge/veterinary-medicine/vet-visit-decisions/cat-sneezing-a-lot) - [Why Is My Cat Sneezing So Much And Coughing](/knowledge/veterinary-medicine/symptom-guides/why-is-my-cat-sneezing-so-much-and-coughing) - [Cat Is Dry Coughing](/knowledge/veterinary-medicine/symptom-guides/cat-is-dry-coughing) - [Cat Coughing Sneezing](/knowledge/veterinary-medicine/symptom-guides/cat-coughing-sneezing) - [Upper Respiratory Infection In Cats Symptoms](/knowledge/veterinary-medicine/symptom-guides/upper-respiratory-infection-in-cats-symptoms) - [Is My Cat Dry Heaving Or Coughing](/knowledge/veterinary-medicine/symptom-guides/is-my-cat-dry-heaving-or-coughing) - [Is Cat URI Contagious to Other Cats? How It Spreads](/knowledge/veterinary-medicine/symptom-guides/is-cat-uri-contagious-to-other-cats) - [Is Feline Herpes Contagious to Other Cats? What to Know](/knowledge/veterinary-medicine/symptom-guides/feline-herpes-contagious-cats) - [Pneumonia in Cats: Treatment and Home Care](/knowledge/veterinary-medicine/symptom-guides/pneumonia-cats-treatment) - [Feline Respiratory Infections: Etiology, Zoonotic Potential, and Contagion](/knowledge/bacteria/pet-bacteria/feline-respiratory-infections-zoonotic-contagion) - [Cat Respiratory Infections: Etiology, Clinical Signs, Zoonotic Potential, and Management](/knowledge/bacteria/pet-bacteria/cat-respiratory-infections-etiology-clinical-signs-zoonotic-potential-management) ## References 1. [Pneumonia in Cats - Cat Owners](https://www.merckvetmanual.com/cat-owners/lung-and-airway-disorders-of-cats/pneumonia-in-cats). Merck Veterinary Manual. 2. [Pneumonia in Dogs and Cats - Respiratory System](https://www.merckvetmanual.com/respiratory-system/respiratory-diseases-of-small-animals/pneumonia-in-dogs-and-cats). Merck Veterinary Manual. 3. [Detection of neutralizing antibody to Feline herpesvirus type 1 in cat serum](https://pubmed.ncbi.nlm.nih.gov/41326258/). Comparative immunology, microbiology and infectious diseases, 2025. 4. [Allergic Pneumonitis in Cats - Cat Owners](https://www.merckvetmanual.com/cat-owners/lung-and-airway-disorders-of-cats/allergic-pneumonitis-in-cats). Merck Veterinary Manual. 5. [EXPRESS: Detection of Mycoplasma species and respiratory pathogens in cats with rhinitis and healthy cats](https://pubmed.ncbi.nlm.nih.gov/42751890/). Journal of feline medicine and surgery, 2026. 6. [Nodular pyogranulomatous pneumonia associated with Besnoitia darlingi infection in a cat](https://pubmed.ncbi.nlm.nih.gov/41782300/). Journal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc, 2026. ## Further Reading - [Merck Veterinary Manual: Cat Owners](https://www.merckvetmanual.com/cat-owners) - [Cornell Feline Health Center: Health Information](https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information) - [American Veterinary Medical Association: Pet Care](https://www.avma.org/resources-tools/pet-owners/petcare)