Feline Herpesvirus: The Most Common Cause of Cat Flu
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Feline herpesvirus-1 (FHV-1) is one of the most common infectious diseases in cats. An estimated 80-90% of cats have been exposed, and many carry the virus for life. While most cats recover from the initial infection, the virus remains dormant in the body and can reactivate during stress, causing recurring upper respiratory symptoms.
- Most cats carry feline herpesvirus for life
- Stress triggers flare-ups (boarding, new pets, moving)
- Signs: sneezing, runny eyes, nasal discharge, eye ulcers
- Kittens and unvaccinated cats are most severely affected
- Antiviral medication can reduce severity and frequency
- Vaccination reduces severity but doesn't prevent infection
Understanding the Virus
FHV-1 is spread through direct contact with infected cats' saliva, nasal secretions, and eye discharge. Kittens often get it from their mothers. After the initial infection (which causes 'cat flu'), the virus retreats to nerve cells where it stays dormant. Stress, illness, or immune suppression can reactivate it, causing flare-ups throughout the cat's life.
Signs and Symptoms
The initial infection causes sneezing, nasal congestion, runny eyes (often clear discharge that can become thick and yellow-green), conjunctivitis (red, swollen eyes), fever, loss of appetite, and lethargy. Some cats develop corneal ulcers (cloudy or painful eyes). Kittens can be severely affected. Chronic carriers may have recurring sneezing and eye issues.
Treatment and Management
There is no cure — treatment manages symptoms and reduces flare-ups. Antiviral medications (famciclovir, cidofovir eye drops) can reduce severity. Supportive care includes keeping the nose clear (steam therapy), encouraging eating (warm, smelly food), and L-lysine supplements (controversial but widely used). Antibiotics may be needed for secondary bacterial infections.
Reducing Flare-Ups
Minimize stress in your cat's environment. Maintain a consistent routine. Provide hiding spots and vertical space. When boarding or moving, use calming pheromones (Feliway). Keep your cat's vaccinations up to date. Multi-cat households may have higher stress levels — ensure enough resources (litter boxes, food bowls, resting spots) for all cats.
- Persistent sneezing with nasal discharge
- Red, swollen, or painful eyes
- Eye discharge that's thick, yellow, or green
- Loss of appetite for more than 24 hours
- Kitten with flu symptoms
- Cloudy or painful eye
RVC
RVC can diagnose and manage feline herpesvirus with antiviral medication, supportive care, and stress management guidance. We also offer the FHV-1 vaccine to reduce severity. Call +853 6677 6611.
+853 6677 6611