Cat Flu in Cats (Feline Upper Respiratory Infection)
Cat flu, or feline upper respiratory infection, is a common illness in cats caused primarily by viral infections. It can affect cats of all ages but is especially concerning in kittens, older cats, or those with weakened immune systems.
Causes
Around 90% of cat flu cases are viral, typically caused by:
- Feline Herpesvirus (FHV):
- Incubation period: 2–6 days.
- Cats often shed the virus for about 2 weeks, though lifelong shedding is possible in some cases.
- The virus targets epithelial cells, leading to damage such as corneal ulcers.
- Most clinical signs resolve within 3 weeks.
- More than 80% of cats that recover become carriers, meaning they can harbor the virus silently and may reactivate it during times of stress.
- Feline Calicivirus (FCV):
- Shedding can last from 30 days to several years.
- Symptoms include:
- Sneezing
- Conjunctivitis (eye inflammation)
- Ocular and nasal discharge
- Oral ulcers (sometimes footpad ulcers)
- Some cats may develop a unique limping syndrome, characterized by fever and shifting lameness.
- FCV is more common in environments with multiple cats, such as shelters or catteries, but up to 10% of household cats may shed the virus at any time.
- Other Bacterial Causes:
- Chlamydophila felis and Mycoplasma felis can contribute to secondary infections.
- Bordetella bronchiseptica may also play a role.
Symptoms
Cats with cat flu may show one or more of the following signs:
- Sneezing
- Runny nose (nasal discharge)
- Eye discharge (conjunctivitis or watery eyes)
- Mouth ulcers or sores on the gums
- Fever
- Loss of appetite
- Lethargy
- In some cases, difficulty breathing or coughing
How It Spreads
Cat flu is highly contagious and spreads through:
- Direct contact with infected cats.
- Sharing food and water bowls or litter trays.
- Sneezing or coughing, which releases virus particles into the air.
Diagnosis
To confirm cat flu, veterinarians may use:
- Swabs from the tonsils, nasal passages, or eyes for testing.
- Diagnostic methods such as PCR (polymerase chain reaction) tests or rapid antigen tests to identify the specific virus or bacteria causing the infection.
Management and Care
Since cat flu is contagious, isolation from other cats is crucial to prevent the spread. Supportive care is often the mainstay of treatment and may include:
- Keeping the cat hydrated.
- Providing a stress-free, warm environment.
- Cleaning their eyes and nose to remove discharge.
- Using appetite stimulants if the cat isn’t eating well.
- Nebulization or steam therapy to help with breathing difficulties.
Prevention
Preventing cat flu involves reducing stress and minimizing exposure to infected cats. Key measures include:
- Vaccinating against common viruses such as FHV and FCV.
- Keeping infected cats isolated from healthy cats.
- Avoiding overcrowded environments, especially in multi-cat households or shelters.
- Regular veterinary checkups to monitor overall health.
Prognosis
With proper care, most cats recover from cat flu in a few weeks. However:
- Cats infected with FHV may become lifelong carriers and experience flare-ups during times of stress.
- Chronic issues such as gingivitis or recurring respiratory symptoms may occur in some FCV-infected cats.