Last updated: May 6, 2026

Cat Upper Respiratory Infection: Symptoms, Treatment & Care

If your cat is sneezing, has watery eyes, and seems generally under the weather, there is a good chance you are dealing with a cat upper respiratory infection. URIs are among the most frequently diagnosed feline illnesses, particularly in shelters, catteries, and homes with multiple cats. While often compared to the common cold in humans, a URI in cats should never be dismissed — especially in vulnerable animals where it can escalate rapidly into a life-threatening condition.

This guide walks you through everything cat owners need to know: what causes a URI, how to recognize the symptoms early, what treatment looks like, how to nurse a sick cat at home, when to seek emergency veterinary care, how to prevent infections in the first place, and why kittens face the highest risk.

What Is a Cat Upper Respiratory Infection?

A cat upper respiratory infection is an infection of the nose, throat, sinuses, and sometimes the eyes. It is caused by viral or bacterial pathogens that target the upper airways — the passages above the lungs. Think of it as the feline equivalent of a cold or flu, although the specific pathogens involved are different from those that infect humans. Cats cannot give URIs to people, and human colds cannot spread to cats.

URIs are the single most common infectious disease seen in cats. Some studies estimate that up to 90 percent of cats in shelter environments will be exposed to URI pathogens at some point during their stay. In multi-cat households, an outbreak can move through every resident cat within days. Understanding the basics of a cat upper respiratory infection helps owners respond quickly and reduce the spread.

Most URIs are self-limiting in otherwise healthy adult cats, meaning the immune system will eventually clear the infection. However, secondary bacterial infections can develop on top of the initial viral illness, complications like pneumonia can arise, and some cats become chronic carriers who shed the virus intermittently for the rest of their lives.

Symptoms of a Cat Upper Respiratory Infection

Recognizing the signs of a cat upper respiratory infection early gives your cat the best chance at a smooth recovery. Symptoms typically appear two to ten days after exposure to the pathogen and can range from mild to severe.

Sneezing is usually the first and most obvious sign. A cat with a URI may sneeze frequently, sometimes in rapid bursts of five or more sneezes in a row. You may notice nasal discharge on nearby surfaces after a sneezing fit.

Nasal discharge often starts clear and watery but can become thick, yellow, or green as the infection progresses or as secondary bacteria become involved. Cats may breathe through their mouths when nasal congestion is severe.

Eye discharge and conjunctivitis are common, particularly with herpesvirus infections. The eyes may appear red, swollen, and weepy. Discharge can mat around the eyes and crust over if not gently cleaned.

Lethargy and reduced appetite accompany most URIs. Cats rely heavily on their sense of smell to stimulate appetite, and a congested cat often refuses to eat — which can lead to dangerous weight loss, especially in kittens.

Fever is common in the first few days. A normal feline body temperature is between 100.5 and 102.5 degrees Fahrenheit. Cats with a URI may run temperatures above 103 degrees.

Other symptoms may include drooling (especially with calicivirus, which causes mouth ulcers), coughing, hoarse meowing, and in severe cases, open-mouth breathing or visible effort to inhale. Ulcers on the tongue, gums, or hard palate are a hallmark of feline calicivirus and can make eating extremely painful.

Causes of Cat Upper Respiratory Infections

Several pathogens can cause a cat upper respiratory infection, but three account for the vast majority of cases. Understanding which organism is responsible can help guide treatment and predict the course of the illness.

Feline Herpesvirus (FHV-1)

Feline herpesvirus type 1, also called feline viral rhinotracheitis, is the most common cause of cat upper respiratory infections. It is responsible for an estimated 40 to 45 percent of all feline URI cases. Herpesvirus primarily affects the nose, throat, and eyes, causing sneezing, nasal congestion, conjunctivitis, and corneal ulcers in severe cases.

One of the most important things to understand about feline herpesvirus is that once a cat is infected, the virus remains in the body for life. It becomes latent in the nerve tissue and can reactivate during periods of stress — such as a move, a new pet in the household, boarding, surgery, or any event that suppresses the immune system. During reactivation, the cat may show symptoms again and can shed the virus to other cats. An estimated 80 percent of cats that recover from a herpesvirus infection become lifelong carriers.

Feline Calicivirus (FCV)

Feline calicivirus is the second most common cause, responsible for roughly 25 to 40 percent of feline URIs. Calicivirus tends to cause milder nasal symptoms than herpesvirus but is distinguished by its tendency to produce painful oral ulcers on the tongue, gums, lips, and palate. Affected cats may drool heavily, paw at their mouths, and refuse to eat because of the pain.

Calicivirus can also cause a limping syndrome in some cats — a transient arthritis that causes lameness and joint pain, often in kittens. In rare cases, a highly virulent strain called virulent systemic feline calicivirus (VS-FCV) can cause a severe, often fatal disease with widespread organ involvement. Cats that recover from calicivirus may shed the virus for weeks to months, and some become chronic carriers.

Chlamydia felis

Chlamydia felis is a bacterial pathogen that primarily causes conjunctivitis rather than the classic sneezing and nasal symptoms of viral URIs. Cats with chlamydial infections typically present with unilateral (one-sided) eye redness and discharge that may spread to the other eye within a few days. Chlamydia is responsible for roughly 5 to 10 percent of feline URI cases and is more common in multi-cat environments. Unlike the viral causes, chlamydial infections respond well to antibiotic treatment, particularly with doxycycline.

Other less common causes of cat upper respiratory infections include Bordetella bronchiseptica (which also causes kennel cough in dogs), Mycoplasma species, and feline reovirus. In many cases, more than one pathogen is present at the same time, making the clinical picture more complicated.

How Cat Upper Respiratory Infections Spread

Understanding how a cat upper respiratory infection spreads is essential for prevention, especially in multi-cat households and shelters. URIs are highly contagious among cats and spread through three primary routes.

Direct contact is the most common transmission route. Cats spread URI pathogens through nose-to-nose touching, grooming each other, sharing food and water bowls, and simply being in close proximity while an infected cat sneezes. A single sneeze can propel virus-laden droplets several feet.

Fomite transmission occurs when the virus survives on objects — food bowls, bedding, litter boxes, toys, clothing, and human hands. Calicivirus is particularly hardy and can survive on surfaces for up to a month in the right conditions. This means you can carry the infection from one cat to another on your hands or clothing without realizing it.

Aerosol transmission happens when viral particles become airborne through sneezing. While most droplets fall within a few feet, in enclosed spaces with poor ventilation — like crowded shelter rooms — airborne transmission can spread the infection rapidly.

Stress is a major amplifier. Cats in stressful environments shed more virus, are more susceptible to infection, and take longer to recover. This is why shelters, boarding facilities, and recently adopted cats are URI hotspots. If you are considering adopting a cat, be aware that many shelter cats arrive with or develop URIs during their stay — this does not make them less worthy of a home, and most recover fully with proper care.

Treatment for Cat Upper Respiratory Infections

There is no cure for viral cat upper respiratory infections — antibiotics do not kill viruses. Treatment focuses on supporting the cat’s immune system, managing symptoms, preventing secondary bacterial infections, and ensuring the cat continues to eat and stay hydrated.

Veterinary-prescribed antibiotics such as doxycycline, amoxicillin-clavulanate, or azithromycin are commonly prescribed even for viral URIs. The antibiotics do not target the virus itself but prevent or treat secondary bacterial infections that commonly develop on top of the viral illness. For Chlamydia felis infections specifically, doxycycline is the antibiotic of choice and typically needs to be given for three to four weeks to fully clear the organism.

Antiviral medications may be prescribed in severe herpesvirus cases. Famciclovir is the most commonly used oral antiviral for feline herpesvirus and has shown good efficacy with relatively few side effects. Topical antiviral eye drops or ointments may be prescribed for cats with corneal ulcers or severe conjunctivitis. L-lysine supplementation was once widely recommended to suppress herpesvirus replication, but recent veterinary research has called its effectiveness into question, and many veterinarians no longer recommend it routinely.

Anti-inflammatory and pain medications may be given to reduce fever and make the cat more comfortable. Non-steroidal anti-inflammatory drugs (NSAIDs) formulated specifically for cats, such as meloxicam, can help reduce fever and inflammation. Never give your cat human medications — acetaminophen (Tylenol) is fatal to cats, and ibuprofen is highly toxic.

Fluid therapy is critical for cats that have stopped eating and drinking. Subcutaneous fluids can be administered at the veterinary clinic or, with proper instruction, at home. Severely dehydrated cats may require intravenous fluids during hospitalization.

Nutritional support is sometimes necessary for cats that refuse food for more than 24 to 48 hours. Appetite stimulants like mirtazapine may be prescribed, or in critical cases, a temporary feeding tube may be placed.

Home Nursing Care for a Cat With a URI

Much of the recovery from a cat upper respiratory infection happens at home. Good nursing care can significantly shorten recovery time and prevent complications.

Keep the nose and eyes clean. Gently wipe away discharge from the nose and eyes several times a day using a soft, warm, damp cloth. Use a separate cloth for each eye to avoid spreading infection. Keeping the nasal passages as clear as possible helps the cat smell food and breathe more easily.

Create steam. Run a hot shower in the bathroom with the door closed and sit with your cat in the steamy room for 10 to 15 minutes, two to three times daily. The moisture helps loosen nasal congestion and makes breathing easier. Do not place the cat directly in or near the hot water.

Encourage eating. A congested cat cannot smell food well, and if the cat cannot smell it, the cat often will not eat it. Warming canned food slightly in the microwave — just a few seconds, then stir to eliminate hot spots — releases more aroma and can stimulate appetite. Strong-smelling foods like canned tuna, baby food (plain meat, no onion or garlic), or warmed chicken broth can entice reluctant eaters. If your cat has not eaten in more than 24 hours, call your veterinarian.

Ensure hydration. Place multiple water bowls around the house. Some cats prefer running water and will drink more from a pet fountain. You can also add water or low-sodium broth to canned food to increase fluid intake.

Isolate the sick cat. If you have multiple cats, keep the infected cat in a separate room with its own litter box, food, water, and bedding. Wash your hands thoroughly and change clothes before interacting with your healthy cats. This isolation should continue until symptoms have fully resolved — typically 7 to 14 days after onset.

Reduce stress. Keep the environment quiet, warm, and comfortable. Provide familiar bedding and minimize disruptions. Stress suppresses the immune system and can prolong recovery or trigger viral reactivation.

Use a humidifier. Running a cool-mist humidifier in the room where the sick cat is staying can help keep airways moist and ease breathing, particularly during dry winter months.

When to See a Veterinarian

While many mild URIs resolve on their own, certain signs indicate that a cat upper respiratory infection has become serious enough to require professional intervention. Do not wait if you observe any of the following.

Not eating for more than 24 hours. Cats, especially kittens and overweight cats, are at risk of hepatic lipidosis (fatty liver disease) when they stop eating for even a day or two. This is a life-threatening condition on its own.

Difficulty breathing. Open-mouth breathing, rapid breathing, labored breathing, or any visible effort to inhale or exhale suggests the infection may have spread to the lower respiratory tract (pneumonia) or that severe congestion is compromising the airway.

Colored or bloody nasal discharge. While some yellow or green discharge is common, thick, persistent discharge or any blood may indicate a serious secondary infection or another underlying condition.

Eye symptoms that worsen. Squinting, cloudiness of the eye, swelling of the eyelids, or discharge that becomes increasingly thick or purulent may indicate a corneal ulcer — a painful complication of herpesvirus that requires urgent treatment to prevent permanent eye damage or vision loss.

Symptoms lasting longer than 10 to 14 days. A typical URI should begin to improve within a week. If symptoms persist, worsen, or recur, the cat may have a secondary infection, a chronic carrier state, or an underlying condition such as feline immunodeficiency virus (FIV) or feline leukemia virus (FeLV) that is compromising the immune response.

Any kitten under 8 weeks old showing URI symptoms. Young kittens dehydrate rapidly, lose body heat quickly, and their immature immune systems struggle to fight infection. A URI that would be mild in an adult cat can be fatal in a neonatal kitten within 24 to 48 hours.

Prevention and Vaccines

Prevention is always better than treatment, and several strategies can significantly reduce the risk of a cat upper respiratory infection.

Vaccination is the cornerstone of URI prevention. The FVRCP vaccine — a core vaccine recommended for all cats — protects against feline viral rhinotracheitis (herpesvirus), calicivirus, and panleukopenia. Kittens typically receive their first FVRCP vaccination at 6 to 8 weeks of age, followed by boosters every 3 to 4 weeks until they are 16 weeks old. Adult cats receive boosters every 1 to 3 years depending on the vaccine type and veterinary guidelines. A separate vaccine for Chlamydia felis is available and may be recommended for cats in high-risk environments.

It is important to understand that FVRCP vaccination does not guarantee complete immunity. Vaccinated cats can still contract herpesvirus or calicivirus, but the illness is typically much milder, shorter in duration, and far less likely to become life-threatening. Vaccination dramatically reduces the severity and shedding of the virus.

Good hygiene is critical, especially in multi-cat households. Regularly disinfect food bowls, water bowls, litter boxes, and shared surfaces. A dilute bleach solution (1:32 ratio of bleach to water) is effective against most URI pathogens, including calicivirus. Wash your hands between handling different cats, particularly if any cat is showing symptoms.

Minimize stress. Provide each cat with adequate resources — at least one litter box per cat plus one extra, separate feeding stations, vertical space, and hiding spots. Reduce overcrowding and introduce new cats gradually. A less stressed cat is a more immunologically resilient cat.

Quarantine new arrivals. Any new cat entering a household should be kept separate from resident cats for a minimum of two weeks. This quarantine period allows time for any incubating infections to manifest before the newcomer comes into contact with the rest of the household. This is particularly important when adopting from a shelter, where exposure to URI pathogens is nearly universal.

Keep cats indoors. Indoor cats have a dramatically lower risk of URI exposure compared to cats that roam outdoors and interact with strays or feral cats of unknown health status. To explore which feline companions might be the best fit for your home, browse our cat breeds directory.

Cat Upper Respiratory Infections in Kittens

Kittens are the most vulnerable population when it comes to cat upper respiratory infections, and they deserve special attention in any discussion of this disease.

Kittens under eight weeks old have immature immune systems that cannot mount the same defense as an adult cat. Their small body size means they dehydrate faster, lose body temperature more quickly, and have less metabolic reserve to sustain them through a period of reduced food intake. A kitten that stops eating and becomes dehydrated can deteriorate from stable to critical within hours — not days.

Neonatal kittens may receive some maternal antibodies through their mother’s colostrum (first milk), but this passive immunity wanes between 4 and 12 weeks of age, creating a window of vulnerability that coincides exactly with the period when kittens are most likely to be entering shelters, foster homes, and new adoptive families.

Herpesvirus infections in kittens can be particularly severe, causing not just the typical sneezing and congestion but also serious eye disease. Severe conjunctivitis in neonatal kittens can cause the eyelids to seal shut with dried discharge, trapping infection behind the lids and potentially destroying the eye. Kittens with sealed eyes need veterinary attention immediately — the lids may need to be gently separated and the trapped material flushed out to save vision.

Calicivirus in kittens can cause the classic oral ulcers plus a painful limping syndrome that, while usually self-resolving, can be alarming for new kitten owners who are unfamiliar with the condition.

If you are fostering or have recently adopted a kitten, watch closely for any signs of sneezing, eye discharge, lethargy, or reduced appetite. Weigh the kitten daily if possible — weight loss is one of the earliest and most reliable indicators that something is wrong. Keep the kitten warm, fed, and hydrated, and do not hesitate to contact a veterinarian at the first sign of illness. Early intervention in kittens can make the difference between a quick recovery and a fatal outcome.

Frequently Asked Questions

Can I catch a cold from my cat with a URI?

No. The viruses and bacteria that cause cat upper respiratory infections are species-specific. Feline herpesvirus, feline calicivirus, and Chlamydia felis do not infect humans. Similarly, human cold and flu viruses do not infect cats. You can safely care for your sick cat without worrying about catching the illness yourself.

How long does a cat upper respiratory infection last?

A typical URI in an otherwise healthy adult cat lasts 7 to 21 days. Most cats begin to improve within 7 to 10 days. However, some cats — particularly those infected with herpesvirus — may experience recurrent episodes throughout their lives, especially during periods of stress. Cats with weakened immune systems, concurrent illnesses, or secondary bacterial infections may take longer to recover.

Can a cat upper respiratory infection go away on its own?

In many healthy adult cats, a mild URI will resolve on its own with good supportive care at home. However, it is always wise to consult a veterinarian, especially if symptoms are worsening, if the cat stops eating, or if eye symptoms are present. Kittens, senior cats, and immunocompromised cats should always receive veterinary attention for a URI, as complications can develop rapidly in these populations.

Is a cat upper respiratory infection contagious to dogs?

Generally, no. The primary URI pathogens in cats — feline herpesvirus and feline calicivirus — do not infect dogs. However, Bordetella bronchiseptica, a less common cause of feline URI, can be shared between cats and dogs. If your cat has been diagnosed with Bordetella and you also have dogs, discuss the risk with your veterinarian.

Should I adopt a shelter cat that has a URI?

Absolutely. A cat upper respiratory infection is common in shelter environments and is not a reflection of the cat’s long-term health. Most cats recover fully with appropriate care. If you adopt a cat that is showing URI symptoms, ask the shelter about any medications the cat is currently on, keep the new cat isolated from any resident pets for at least two weeks, and follow up with your own veterinarian. A URI should not deter you from giving a deserving cat a loving home.

My cat keeps getting URIs — why?

Recurrent URIs are most commonly caused by feline herpesvirus reactivation. Once a cat is infected with herpesvirus, the virus remains dormant in the body and can reactivate during periods of stress, illness, or immune suppression. Managing stress, maintaining a consistent routine, ensuring good nutrition, and keeping vaccinations current can help reduce the frequency and severity of recurrent episodes. Your veterinarian may also recommend antiviral medication during flare-ups.