What is Cat Flu?
Cat flu, also known as feline upper respiratory infection (URI), is a common respiratory illness in cats caused by viruses or bacteria. The most common pathogens are feline herpesvirus, feline calicivirus, Chlamydophila felis, and Bordetella bronchiseptica (Trudell).
The symptoms of cat flu are usually similar to a human cold, including sneezing, runny nose and eyes, fever, lethargy, loss of appetite, and discharge from the nose and eyes. In some cases, ulcers can develop on the tongue, mouth, and nose. Cat flu symptoms can range from mild to severe depending on the pathogen involved and the cat’s immune health.
While cat flu is rarely fatal by itself, secondary infections can develop and lead to more serious conditions like pneumonia. Kittens and senior cats tend to experience more severe symptoms from cat flu.
Causes of Cat Flu
The most common causes of cat flu are viral infections. The two main viruses that cause cat flu are feline herpesvirus (FHV-1) and feline calicivirus (FCV). These viruses are extremely contagious and spread rapidly between cats through respiratory secretions and discharges from the eyes, mouth, and nose.
FHV-1 is spread through direct contact and shared spaces like food bowls, litter trays, or bedding. Once a cat is infected, the virus stays dormant in their body for life and can reactivate during times of stress. FCV is similarly spread through saliva and secretions. The virus is fragile and does not survive long in the environment, but it spreads quickly during close interactions between cats.[1]
In addition to FHV-1 and FCV, other viruses like feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) can weaken a cat’s immune system and make them susceptible to secondary infections that cause flu-like symptoms.
Diagnosing Cat Flu
Diagnosing cat flu starts with a veterinary examination of the cat’s symptoms. The vet will look for common signs of upper respiratory infection like sneezing, nasal discharge, eye discharge, fever, and lethargy. They will also examine the mouth, nose, throat, and eyes for inflammation, ulcers, or other abnormalities.
To confirm the diagnosis, the vet may take swab samples from the eye, mouth, or throat and analyze them for the presence of pathogens. Common tests look for feline herpesvirus, calicivirus, Chlamydia, and mycoplasma bacteria (Zoetis). These lab tests can identify the specific causative agent, but are not always necessary for diagnosis.
Cats with suspected cat flu are often diagnosed based on clinical signs and examination alone. However, testing may be recommended in severe cases to guide treatment options. At home, owners can monitor for symptoms but veterinary assistance is needed to officially diagnose cat flu and provide appropriate care.
Cat Flu Treatment
There is no specific treatment that can cure cat flu, but vets may prescribe medications and supportive care to help ease symptoms and prevent secondary infections. The main treatments include:
- Antibiotics like doxycycline to prevent or treat secondary bacterial infections.
- Anti-inflammatory drugs like meloxicam to reduce fever, pain, and upper respiratory inflammation.
- Supportive care such as fluids, nutritional support, and nasal decongestants to relieve congestion.
Vets may recommend hospitalization for cats with severe symptoms to provide intensive care and monitoring. Cats with cat flu should be kept warm, hydrated, and calorie-intake monitored. Owners can help relieve congestion using humidifiers or steam from the shower. The recovery period varies but symptoms usually resolve within 2-4 weeks with appropriate treatment and home nursing.
Prognosis for Cat Flu
The prognosis for a cat with cat flu depends on the severity of the infection and any complications that arise. In mild cases, most cats will fully recover within 2-4 weeks with supportive care and treatment. However, complications can lead to more serious illness and prolonged recovery times.
The mortality rate for cat flu is generally quite low, with fewer than 5% of cases resulting in death when proper veterinary care is provided. Young kittens, senior cats, and those with weakened immune systems are most at risk for life-threatening complications from cat flu.
For mild infections, recovery time is around 1-2 weeks. More severe cases involving pneumonia or other secondary infections can take up to 6 weeks for full recovery. Relapses and flare-ups may occur as well, especially with the feline herpesvirus that causes chronic lifelong infection.
With prompt veterinary care and proper treatment, most cats fully bounce back from cat flu. However, severely afflicted cats may suffer long-term effects like chronic respiratory problems. Preventing secondary infections and providing good supportive care improves recovery outlook.
Complications of Cat Flu
One of the most common and serious complications of cat flu is secondary bacterial infections. The viruses that cause cat flu, feline herpesvirus and feline calicivirus, damage the respiratory tract and suppress the immune system. This makes cats more prone to secondary infections by bacteria like Bordetella bronchiseptica and Streptococcus species (https://wingsandpaws.com/understanding-the-difference-between-cat-flu-and-a-cold-symptoms-treatment-and-prevention).
These secondary infections can lead to potentially life-threatening pneumonia. Pneumonia causes inflammation in the lungs that fills the air sacs with fluid and pus. This makes breathing very difficult for cats with cat flu. Pneumonia can be fatal if not treated promptly with antibiotics, oxygen therapy, and supportive care. According to one source, pneumonia occurs in over 50% of cats hospitalized for cat flu and is a leading cause of death from the disease (https://bushyparkvets.ie/vaccinations/).
Other possible complications from cat flu include:
- Dehydration from reduced eating and drinking
- Malnutrition from prolonged lack of appetite
- Damage to eyes and mouth from viral infection
- Chronic nasal and eye discharge
- Chronic sneezing and coughing
While most cats recover fully from an uncomplicated case of cat flu, the potential for secondary infections and other complications makes prompt veterinary care essential. Vaccination, good nutrition, and stress reduction help prevent complications in cats infected with cat flu viruses.
Caring for a Cat with Cat Flu
Caring for a cat with cat flu requires keeping the cat comfortable and isolated from other pets to prevent spreading the infection. Nursing care at home is essential for helping cats recover.
Isolation is important for cats with cat flu. Keep the sick cat separated from other household pets in a comfortable, warm, and quiet room. Place food, water, litter box, bedding, and toys in the isolation room so the cat has everything they need.
Provide supportive nursing care at home. Gently wipe away any nasal or eye discharge with damp cotton wool several times a day. Make sure the cat is eating and drinking enough. Offer smelly foods or warming canned food to stimulate appetite if needed. Keep the nose and eyes clean to prevent secondary infections.
Monitor the cat’s symptoms and energy levels. Alert the vet if symptoms worsen or the cat seems lethargic. Administer any medication as prescribed by the vet. Keep up nursing care and isolation until symptoms have resolved.
With supportive home care and isolation, most cats can recover fully from cat flu within 2-4 weeks. Consult the vet if symptoms persist longer than expected. Avoid exposing recovered cats to infected cats, as reinfection is possible.
Preventing Cat Flu
Vaccination is the best way to prevent cat flu. There are vaccines available that protect against the most common cat flu viruses, like feline herpesvirus and feline calicivirus. According to the Blue Cross, “Two doses of vaccine are needed initially, followed by regular boosters to maintain immunity.”
Zoetis also states that “Vaccines help to reduce the severity of disease but they do not always prevent infection.” So while the vaccine may not completely prevent cat flu, it can reduce symptoms if a cat does become infected.
In addition to vaccination, good hygiene can help prevent the spread of cat flu viruses. Isolating infected cats, disinfecting food bowls and litter trays daily, and washing hands before and after handling cats can limit transmission. Avoiding multi-cat households and crowded shelters can also reduce exposure.
While challenging to fully prevent, vaccination and cleanliness provide the best defense against cat flu infection.
Life Expectancy with Cat Flu
The life expectancy for cats with cat flu depends on several factors, including how severe the initial infection is and if it becomes a recurring or chronic illness. In mild cases, cat flu may not have any significant impact on lifespan.
However, recurrent infections or chronic manifestations of cat flu can potentially shorten lifespan. According to the RSPCA, cats that have compromised immune systems and develop secondary infections are at higher risk for reduced life expectancy.[1] The chronic nasal discharge associated with cat flu can predispose cats to sinus and dental infections over time.[2]
With supportive care and veterinary treatment, the outlook for cats with cat flu can be good. Antibiotics may be prescribed to prevent secondary infections and anti-inflammatory medications can help manage symptoms. Keeping the cat’s environment clean and reducing stressors can also help minimize recurrences.[3]
While cat flu itself is rarely fatal, the secondary problems it can cause may gradually impact lifespan if not well controlled. Working closely with your veterinarian and providing excellent care at home are the best ways to optimize life expectancy for a cat with chronic cat flu.
[1] https://kb.rspca.org.au/knowledge-base/what-is-cat-flu-and-how-is-it-managed/
[2] https://www.purina.co.uk/articles/cats/health/symptoms/cat-flu
[3] https://www.cats.org.uk/northherts/feature-pages/about-cat-flu
Outlook for Cats with Cat Flu
The prognosis for cats with cat flu is generally good if proper treatment is administered early on. According to Trudell Animal Health, most cats recover fully from cat flu if treated promptly before the condition worsens. With supportive care from a veterinarian, including fluids, anti-inflammatory medications, and antibiotics if secondary infections develop, many cats make a complete recovery within 2 to 4 weeks.
According to the PDSA, while there is no cure for cat flu, treatment can help reduce symptoms, speed up recovery, and limit future flare-ups. Cats who receive timely veterinary care have a good prognosis, though it may take several weeks for symptoms to fully resolve. With appropriate treatment, the vast majority of cats go on to live a normal lifespan.
The Blue Cross notes that many cats will recover fully and are no longer contagious after one or two years. So while cat flu can be serious if left untreated, the long-term outlook for most cats is very good following proper medical care and recovery time.
