Upper Respiratory Tract Infections (FURTIs) in Cats

The symptoms of URTIs present vary slightly depending on which bacteria or virus is causing the infection. Along with the above symptoms, more specific symptoms of each pathogen include:

• Feline herpesvirus: Cats may squint or close their eyes due to damage to the eye surface. Swelling of the tissues around the eyes is common.
• Feline calcivirus: Cats may show difficulty breathing due to development of pneumonia. Some infections affect multiple organs, causing swelling of the head and limbs, hair loss, crusting skin sores, and yellow gums. In rare cases, cats may show lameness or joint pain.
• Chlamydiosis: Clear discharge from the eyes that becomes yellow and cloudy over time is a common symptom.

The severity of URTIs also varies according to the extent of the infection, overall health, and age of the cat.

Secondary conditions develop in some cases. These include pneumonia, recurring conjunctivitis or keratitis (infections of the membranes around the eye or the eye surface), as well as various types of bacterial infections.

URTIs are very common and usually pose little long term risk to cats. Cases where URTIs pose an increased risk include:

• Kittens
• Very old cats
• Feral cats
• Immunosuppressed or cats diagnosed with feline leukemia virus or feline immunodeficiency virus
• Cats with chronic illness, especially respiratory diseases like asthma or Heartworm-Associated Respiratory Disease (HARD)
• Affected cats who refuse to eat due to nasal congestion or mouth sores

The most significant secondary symptom is a lack of appetite due either to nasal congestion or sores in the mouth. A cat needs to eat at least a little everyday. In cases where this is not the case, prompt veterinary care is required. Left untreated, a cat that is refusing to eat can develop life-threatening complications such as hepatic lipidosis.

Cats who stop eating or continue to have URTI symptoms after 10 days require prompt veterinary care. Cats that are immunosuppressed or positive for feline leukemia virus or feline immunodeficiency virus should also receive prompt veterinary care when displaying symptoms of URTIs. Serious symptoms such as extreme lethargy, pale gums, or difficulty breathing require emergency veterinary care.

Common causes of URTIs are bacterial or viral infection. The three most common pathogenic agents are:

• Feline viral rhinotracheitis (feline herpes or FVR)
• Feline calicivirus (FCV)
• Feline chlamydiosis (Chlamydia)

Fungal infection and protozoal infections may also be the cause, though less commonly. In some cases, infections with two or more of these agents occur at the same time.

URTIs cause inflammation of the nasal passages, sinus linings, and eye linings.

Cats with typical symptoms that have not been tested for FeLV or FIV require immediate testing to eliminate these as possible underlying causes. In cases where these tests are negative, determining the infecting agent causing symptoms is necessary to ensure effective treatment. Diagnostic tools include physical exam and nasal or oral swabs or scrapes to determine the infectious agent.

Most mild URTIs do not require veterinarian care. Cleaning the cat’s eyes and nose to clear any excess liquid or crusts, relieving congestion by placing the cat in a steamy bathroom, and close observation for worsening symptoms is often sufficient for full recovery. Providing small, warmed, frequent canned food is advised to encourage eating. There are no safe over-the-counter decongestant medications for cats.

Veterinarian care IS required for URTIs under certain conditions. Care is required if the cat:

• is unable to eat for more than a day
• is not vaccinated
• is immunosuppressed
• has or is suspected of having Feline Immunodeficiency Virus (FIV) or Feline Leukemia Virus (FeLV)
• does not improve after 10 days
• demonstrates serious symptoms such as profound lethargy, pale gums, or difficulty breathing

In cases where treatment is warranted, strategies include:

• Antibiotics
• Antivirals
• Antifungals
• Saline and/or medicated nasal drops or nebulization
• Eye drops or ointments
• IV fluids
• Nutritional support
• Oxygen supplementation

Most mild cases of URTIs caused by FVR or FCV resolve within 5-10 days. In severe cases of viral infection, or in cases of chlamydiosis, symptoms do not resolve for several weeks. The prognosis for most URTI cases that respond to treatment is good. Some cases, such as FCV affecting other organs, have a guarded prognosis.

If the pathogenic agent is FVR, it remains in the body in an inactive state for the remainder of the cat’s life. During times of stress, the virus can reactivate, causing another URTI.

The pathogenic bacteria and viruses associated with FURTIs are contagious. These viruses and bacteria travel easily from cat to cat, especially among those living in close proximity. Transmission occurs through aerosol droplets from sneezes, as well as from contact with objects or people that carry the bacteria or virus. Cats showing symptoms should be isolated from all other cats until symptoms resolve.

Vaccines are available for FVR and FCV. These vaccines protect cats from a significant proportion of the viruses’ effects, though they do not prevent infection entirely. Vaccination in combination with keeping cats indoors and reducing exposure to overcrowding, stress, and sick cats provides good protection against URTIs.

URTIs are common in cats, especially those living in close contact with other cats. Cats in multiple-cat homes, shelters, feral cat colonies, pet stores, and breeding catteries are especially susceptible.

Home treatment of mild cases includes:

• Isolation
• Hot, steamy bathroom
• Wiping of mucus from eyes and nose
• Warm canned food in frequent, small amounts

Veterinary treatment of serious URTIs or for cats who are susceptible to extreme infection include:

• Antibiotics
• Antivirals
• Antifungals
• Nose drops
• Eye drops
• IV fluids
• Nutritional support
• Oxygen