WHAT?
Feline upper respiratory infections (URI) are highly contagious infections with one or more viruses and/or bacteria.  The organisms most commonly involved are feline herpesvirus 1 (FHV-1), feline calicivirus (FCV), Bordetella bronchiseptica, Chlamydophila felis and Mycoplasma.

HOW?
URI may develop from a single organism or it may be a mixed infection.  Mixed infections often begin with FHV-1 or FCV.  Direct contact with infected secretions is the most common way that URI is spread from cat to cat.  FCV is easily transmitted through contact with objects like bedding, food and water bowls, litterboxes and even via the skin/clothes of owners.  Sometimes initial disease is followed by a period of dormancy, when the disease hibernates and the cat does not show any signs of illness.  Cats infected with FHV-1, FCV, Bordetella or Chlamydophila often become life-long carriers and intermittently show clinical signs, especially during times of stress.

SIGNS?
The most common signs are nose and eye discharge, conjunctivitis, lethargy and decreased appetite.  Sneezing and fever may also occur.  FHV-1 infection may cause salivation and various eye diseases.  FCV infection may cause oral ulcers.  Severe conjunctivitis may be the only sign with Chlamydophila.  Bordetella infection may cause coughing.  Lameness may develop with FCV and Mycoplasma infections.  Complicated infections can cause pneumonia.  Severe URIs, especially in young cats, can cause permanent damage to the nasal passages and these cats may have life-long upper respiratory problems like nasal congestion, conjunctivitis and chronic bacterial infections of the nose and sinuses.

TEST?
Most of the time URIs are diagnosed from the clinical signs and the history, especially if the cat has recently experienced a stressful situation or if the cat has just come from a shelter-type location.

In cats with more severe disease, routine laboratory tests may be recommended like chest x-rays, especially if pneumonia is suspected.  Conjunctival scrapings, oral swabs and samples from the trachea may be submitted to identify the organism involved.  Skull x-rays, CT scan or MRI may be needed in cats with chronic nasal disease.  Rhinoscopy (examination of the nose with a fiberoptic viewing scope) may also be warranted in more advanced cases.

TREATMENT?
Treatment of uncomplicated URI is mainly supportive.  Smell is a major motivation for any cat’s appetite.  When URI signs are active, the nasal secretions make smelling the food difficult.  Warming the food and offering strong-smelling food can help.  Appetite stimulants are also available.  Humidifiers or having the cat sit in a steamy bathroom can loosen respiratory secretions and improve breathing.  Fluid therapy can be helpful.  Antibiotics and eyedrop medications may be indicated when a bacterial component is suspected.  Oral L-Lysine may be used if FHV-1 infection is suspected.  L-lysine helps to decrease the severity and shorten the duration of signs.

Cats with pneumonia require hospitalization, IV fluids, antibiotics and supplemental oxygen.  Inhalation therapy with saline, bronchodilators and antibiotics may also be recommended.

PREVENTION?
URI is transmitted very easily - isolate any cat who is showing signs of a URI.  Keep recovered cats away from any unvaccinated or immune-compromised cats.  Most of the organisms that cause URI are inactivated by bleach.  Disinfect all contaminated cages, bowls and litterboxes with bleach diluted in water (1 part bleach to 30 parts water).  The FVRCP vaccine is available for protection against FHV-1 and FCV.  Vaccines do not prevent all infections but they decrease the severity of the disease.  Wash your hands after handling any cat showing active URI signs.

PROGNOSIS?
For most cats the prognosis is very good.  URI can be life-threatening, however, in kittens, geriatric cats, nursing mothers and any cat whose immune system is already compromised by other illnesses.  For cats with pneumonia, the prognosis depends on the severity of the pneumonia and the presence of other diseases.

Schedule an appointment with us today to discuss how we can help you manage your cat’s URI or how to keep your cat URI-free!