Can Humans Give Cats Cold Sores?

What are cold sores?

Cold sores, also known as fever blisters are small fluid-filled blisters that develop on or around the lips. They are caused by the herpes simplex virus (HSV-1), which is transmitted by direct contact. Eventually, the blisters erupt, scab over and finally heal. After an initial outbreak, the virus remains dormant in the nerve cells near the site of infection. Periodically, the virus can reactivate and cause new outbreaks. The frequency of these outbreaks can vary from person to person and can be influenced by a number of factors such as stress, illness, or hormonal changes.

Can humans give cats cold sores?

Humans cannot transmit cold sores to cats the herpes simplex virus 1 is primarily a human virus. Cats are affected by a strain of herpes virus which is caused by the feline herpesvirus type 1 (FHV-1). Just as humans can’t transmit HSV-1 to cats, cats can’t transmit FHV-1 to humans. There are over 100 herpes virus strains, each strain is host-specific (canine, equine, feline, molluscs, human etc).

The virus is species-specific, which means that each herpes virus has evolved to infect and replicate in a certain host species. For example, HSV-1 and HSV-2 (responsible for genital herpes) are adapted to infect and replicate in human cells. FHV-1 is similar to the human herpes virus, but is not the same virus, and cannot infect humans. Herpes viruses have evolved to be highly specific in their host range, meaning that they typically infect only certain species or groups of related species. This specificity is due to the way that herpes viruses interact with host cells, including the specific receptors on the surface of cells that the virus uses to gain entry.

While humans cannot give cats a cold sore, it is good practice to avoid direct contact between a cat and an active cold sore lesion, to avoid the risk of secondary infections. Keep the area clean and dry, and do not share towels, kitchen utensils or drinks during an active outbreak. Also be aware that while humans can’t catch or transmit FHV-1 to cats, it is still possible to infect cats if we have been in contact with an infected cat, and then transmit the virus via our hands, clothing or fomites (towels, food bowls etc).

What is feline herpesvirus?

The feline herpesvirus is a highly contagious upper respiratory disease of cats caused by feline herpesvirus type 1 (FHV-1). An upper respiratory disease refers to infections in the eyes, nose, throat and sinus areas and is similar to a cold or flu in humans. Symptoms of feline herpesvirus can include the following:

Due to the highly contagious nature of FHV-1, isolate healthy cats from sick cats. Vaccination remains the most effective way to prevent FHV-1 infection in cats. Kittens, seniors and cats in cramped or stressed environments are at the greatest risk.

Treatment of feline herpesvirus is supportive care and in some cases, antiviral medications. Antibiotics are not effective against herpesvirus, but may be necessary to treat secondary infections which may develop.


  • Humans cannot transmit cold sores to cats as herpes viruses are species specific
  • Herpes simplex virus 1 (HSV-1) is the virus responsible for cold sores in humans
  • Feline herpesvirus affects felines and presents as flu-like symptoms, cats cannot transmit feline herpesvirus to humans but humans can spread the virus from an infected cat via clothing or on their skin


  • Julia Wilson, 'Cat World' Founder

    Julia Wilson is the founder of Cat-World, and has researched and written over 1,000 articles about cats. She is a cat expert with over 20 years of experience writing about a wide range of cat topics, with a special interest in cat health, welfare and preventative care. Julia lives in Sydney with her family, four cats and two dogs. Full author bio

    View all posts