Feline Herpesvirus (FHV-1) Complete Guide | Long-term Management, Recurrence Prevention, and Immune Support Care for Feline Upper Respiratory Infection

Feline Herpesvirus Type 1 (FHV-1) is one of the most common causative viruses of feline upper respiratory infection, commonly known as "feline cold." Most infected cats remain latently infected with the virus in their bodies even after initial infection and experience recurrence when their immune system weakens. This article provides a detailed explanation from the characteristics, symptoms, and transmission routes of FHV-1 through long-term management, recurrence prevention, and home care methods.

What is Feline Herpesvirus (FHV-1)?

FHV-1 is a DNA virus belonging to the Alphaherpesvirinae subfamily and is a pathogen unique to cats. It does not infect humans or dogs. Infected cats typically harbor the virus latently in the trigeminal ganglia throughout their lifetime and reactivate during stress or immunosuppressed states.

Viral Infectivity: FHV-1 is relatively unstable in the environment and survives only 18-24 hours. However, it is found in high concentrations in the nasal discharge, eye discharge, and saliva of infected cats and spreads very rapidly through direct contact or droplet transmission (such as sneezing).

Cats at Higher Risk of Infection: - Cats in multi-cat households - Rescue cats and shelter-origin cats - Kittens and elderly cats with low immune function - Cats in high-stress environments

Main Symptoms and Signs of Severity

FHV-1 symptoms range from mild to severe with individual variation.

Typical Symptoms

• Sneezing (frequent and repeated)
• Nasal discharge (clear to yellowish-green purulent)
• Conjunctivitis (eye redness and discharge)
• Keratitis or corneal ulcers (squinting and tearing)
• Loss of appetite and lethargy
• Mild fever

Signs of Severity

If any of the following symptoms appear, take your cat to a veterinarian immediately.

• Difficulty breathing or mouth breathing