What It Is
Feline herpesvirus type 1 (FHV-1) is a common and highly contagious virus that causes upper respiratory infections in cats. It’s the primary cause of feline viral rhinotracheitis (FVR), which is just a fancy way of saying your cat may have a runny nose, watery eyes, sneezing fits, and possibly a fever. Once infected, a cat usually carries the virus for life.
FHV-1 is not related to the human herpes virus and cannot be transmitted to people.
🐾 Common Symptoms
Symptoms typically affect the eyes, nose, throat, and sometimes the lungs.
- Sneezing (often frequent and sudden)
- Runny nose
- Watery or gooey eyes
- Conjunctivitis (swollen or red eyelids)
- Eye ulcers (corneal ulcers)
- Drooling
- Loss of appetite
- Lethargy
- Fever (usually low-grade)
In kittens or stressed adult cats, symptoms can become more severe.
🦠 Causes
FHV-1 is transmitted through:
- Direct contact with infected cats
- Sharing food bowls, litter boxes, or bedding
- Sneezing or saliva droplets in the air
- Grooming between cats
It’s especially common in multi-cat households, shelters, and catteries.
Once a cat is infected, the virus stays dormant in the body and can reactivate during times of stress, illness, or immune suppression, just like cold sores in humans. That means even after your cat seems better, the virus may still be present and can flare up later.
🔍 Diagnosis
Vets usually diagnose FHV-1 based on symptoms and medical history. Diagnostic tests (like PCR testing or virus isolation) are available but not always necessary unless symptoms are severe or chronic.
If eye ulcers or more serious symptoms are present, your vet may perform:
- Fluorescein eye staining
- Conjunctival swabs
- Complete physical exam
- Bloodwork (to rule out other infections)
💊 Treatment
There’s no cure for herpesvirus, but supportive care can manage symptoms and reduce flare-ups.
Typical treatment options:
- Antiviral medications: e.g., Famciclovir (most commonly used in cats)
- Lysine supplements: once popular, now considered less effective and no longer universally recommended
- Eye drops or ointments: for conjunctivitis or corneal ulcers
- Nasal decongestants or saline drops
- Antibiotics: only if a secondary bacterial infection is present
- Appetite stimulants & fluids if the cat is eating poorly or dehydrated
Stress management and a consistent, low-stress environment play a huge role in reducing flare-ups.
🩺 Prognosis
Most cats recover from initial infections with supportive care, but FHV-1 is a lifelong virus. Flare-ups can happen throughout your cat’s life, especially during stressful events or other illnesses.
The good news? Many cats with FHV-1 live long, healthy lives with occasional mild symptoms or none at all.
💡 Cat Owner Note
If your cat has watery eyes or keeps sneezing like they’re reenacting an old cartoon, don’t panic. Herpesvirus is common and manageable with the right care. Keep their environment calm, follow your vet’s treatment plan, and keep tissues handy.
❓ Frequently Asked Questions About FHV-1 in Cats
Is feline herpes contagious to humans?
No. Feline herpesvirus is species-specific and cannot infect humans.
Can a cat be cured of FHV-1?
No, but symptoms can be managed, and many cats live normal lives with occasional flare-ups.
How long does a flare-up last?
Most episodes resolve within 1 to 3 weeks with proper care. Chronic or severe cases may take longer.
Can indoor cats get FHV-1?
Yes, especially if they were exposed as kittens, came from a shelter, or live with another infected cat.
How do I prevent my cat from spreading herpes to other cats?
Isolate symptomatic cats, wash your hands between interactions, and don’t share bowls or litter boxes during flare-ups.
Is the FVRCP vaccine effective against FHV-1?
Yes, the FVRCP vaccine protects against feline viral rhinotracheitis (caused by FHV-1). It doesn’t prevent infection entirely, but it reduces severity and duration of illness.
What causes flare-ups?
Stress, illness, surgery, moving homes, introducing new pets, or any major disruption to routine.