Can Cats Get Colds? Cat Flu Explained

Reviewed by Dr. Ameer Hamza, DVM

If your cat is sneezing, has a runny nose, and looks miserable, you might wonder whether they have caught a cold. The short answer is yes — cats do get a viral respiratory illness that closely resembles a human cold in its symptoms, commonly called cat flu. It is caused by different viruses than human colds, it is not contagious between cats and humans, and it ranges from mild and self-resolving to severe and dangerous depending on the cat's age, immune status, and which virus is responsible. This guide covers the causes, signs, home care, and when to call the vet.

What Causes Cat Flu?

Cat flu is not caused by a single virus but by a combination of viral (and sometimes bacterial) pathogens. The two primary viral causes are: Feline herpesvirus-1 (FHV-1) — a very widespread herpesvirus that is endemic in the cat population. Primary infection occurs most commonly in young cats and kittens and causes classic upper respiratory signs plus conjunctivitis. After recovery, the virus establishes a latent infection that can reactivate during stress. FHV-1 is highly contagious through direct contact and shared items. Feline calicivirus (FCV) — another highly contagious respiratory virus that tends to cause more oral involvement than herpesvirus, including painful mouth and tongue ulcers. FCV exists as multiple strains of varying severity. Secondary bacterial infections — particularly Chlamydophila felis, Bordetella bronchiseptica, and Mycoplasma — commonly complicate viral cat flu, causing worsening or prolonged illness.

Signs and Severity

Mild cat flu in a healthy adult cat: sneezing, clear nasal discharge, mild watery eyes, slightly reduced appetite, and perhaps a day or two of lethargy. This typically resolves without treatment in one to two weeks. Moderate cat flu: thick, coloured nasal discharge, conjunctivitis with ocular discharge, significantly reduced appetite, lethargy, and possibly a low fever. Home care and sometimes veterinary treatment are appropriate. Severe cat flu (particularly in kittens, elderly cats, or immunocompromised cats): heavy nasal discharge blocking the nostrils, eyes crusted shut, complete anorexia, dehydration, possible pneumonia (breathing difficulty), and in kittens — life-threatening illness. Kittens with severe cat flu can die, particularly from dehydration and secondary pneumonia. Ocular herpesvirus in kittens before their eyes have fully matured can cause corneal scarring and permanent vision damage.

Home Care for Mild Cases

For an otherwise healthy adult cat with mild cat flu signs and who is still eating and drinking: gently clean nasal and ocular discharge with a clean damp cloth several times daily — keeping the nostrils clear is important because cats cannot smell blocked food and will stop eating. Warm food slightly to intensify the aroma and encourage eating. A humidifier in the room or five minutes in a steamy bathroom can ease nasal congestion. Ensure fresh water is available. Isolate from other cats to prevent spread. Monitor closely for deterioration — a cat that stops eating entirely, develops laboured breathing, or whose eyes develop significant discharge or swelling needs a vet visit promptly.

Veterinary Treatment

Vets treating cat flu typically address secondary bacterial infection with antibiotics, provide supportive care (anti-nausea medication if vomiting, fluid support if dehydrated, assisted feeding if anorexic), and treat specific complications such as eye infections with topical antibiotic drops. There is no specific antiviral treatment for FHV-1 in standard practice, though topical antivirals (cidofovir) are used for herpesvirus corneal ulcers. L-lysine supplementation is often recommended as an adjunct — it competes with arginine, an amino acid required for herpesvirus replication, and may reduce viral shedding and disease severity. Kittens with severe cat flu require intensive supportive care and should be seen urgently.

Frequently Asked Questions

Can cats catch colds from humans?

No — cat flu viruses are species-specific and cannot infect humans. Human cold viruses cannot infect cats. The illnesses look similar but the pathogens are entirely different.

What are the signs of cat flu?

Sneezing, nasal discharge, conjunctivitis, reduced appetite, lethargy. Mouth ulcers are more typical of calicivirus. Eye involvement is more typical of herpesvirus.

How do I care for a cat with cat flu at home?

Clear nasal and eye discharge, warm food to encourage eating, humidify the air. Monitor for worsening. See a vet if the cat stops eating, develops eye ulcers, or has difficulty breathing.

Does the cat flu vaccine prevent infection?

It significantly reduces severity but does not prevent infection or carrier status. Vaccinated cats develop much milder illness than unvaccinated cats. All cats should be vaccinated.

Why does my cat keep getting recurring cat flu?

Latent FHV-1 reactivation during stress. The virus establishes lifelong latency after first infection. L-lysine, stress management, and prompt treatment of flares are the mainstays of management.

For comprehensive cat health guidance including vaccination schedules, see the complete cat care guide.

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Disclaimer: This article is for educational purposes only. Kittens with cat flu can deteriorate rapidly — seek veterinary care promptly if a kitten is not eating or appears severely unwell.