Cat Upper Respiratory Infection: Treatment and Prevention

Upper respiratory infections are among the most common illnesses in cats, particularly in rescue environments. Understanding transmission, treatment, and prevention protects both individual cats and colony health.

Key Facts

Feline herpesvirus and calicivirus are responsible for the majority of cat upper respiratory infections
Symptoms include sneezing, nasal discharge, eye discharge, fever, and reduced appetite
Herpesvirus becomes latent after initial infection and can reactivate during stress or illness
Kittens, unvaccinated cats, and immunocompromised individuals face the highest severity risk
Vaccination significantly reduces disease severity even when it cannot prevent infection entirely
Shelter environments with crowding, stress, and shared air space are high-risk transmission settings

Welfare Considerations

Upper respiratory infections cause significant discomfort — nasal congestion alone can prevent cats from smelling food, triggering appetite loss and rapid deterioration. The chronic nature of herpesvirus, with recurring flare-ups during stressful periods, means some cats live with intermittent suffering throughout their lives. Vaccination and stress reduction are the most important preventive measures.

What You Can Do

Ensure your cat is vaccinated against herpesvirus and calicivirus (part of the standard FVRCP vaccination)
Isolate new cats from existing household cats for at least two weeks when introducing them
Minimise stress in your cat's environment, particularly during household changes
Seek veterinary care promptly for any cat showing signs of respiratory illness
Support rescue organisations in implementing proper isolation protocols
Consider L-lysine supplementation for cats with chronic herpesvirus (discuss with your vet)