Feline Herpesvirus
Herpes. No, I am not talking about cold sores, trips to Vegas, or people who study reptiles and amphibians. This blog post is about one of the most common reasons feline owners bring their cat to the vet: Feline Viral Rhinotracheitis (FVR) or feline Herpesvirus. While Herpesvirus is a gigantic group of viruses, the one I am talking about today is specific to cats. The goal of this article is to help owners to identify symptoms as well as how to prevent FVR.
Feline Viral Rhinotracheitis is an infection/inflammation of the nose or throat caused by feline Herpesvirus. As your sex ed teachers probably said, herpes is forever. While they probably weren't talking about your cat, it holds true regardless. In cats, the disease is transmitted by contact or through contaminated surfaces. Most times that we see the condition in a veterinary clinic, it is in a young or immunocompromised patient.
Clinical signs - While we may not see clinical signs directly from the virus, in the clinic, we will see secondary symptoms caused by bacterial infection. Usually, this involves sneezing, runny nose, goopy eyes, and squinting. However, on certain occasions, the symptoms may be more severe (here’s my previous blog post about my cat Stevie who lost both eyes to suspected severe FVR).
Diagnostics - The best diagnostic test a veterinarian can do is get a thorough history from a client. FVR has symptoms that fit many different diseases. However, being one of the most common diseases we see, there are certain things an owner tells us while we are getting a history that points us in the right direction. A big tip to saving money at the vet is to have a complete history, including from pet sitters, places you adopt from, and if you've given any over-the-counter meds (your vet will fight you if you have, but if you're honest about it we will try to make it an honest fight.) We see FVR most commonly in kittens or immunosuppressed cats, especially outdoor cats around other cats. Cats that have herpes will have an event that lowers their immunity: a new pet, moving, vet visits, flea infestation (this is one reason why when cats get fleas, they can also have runny eyes, sneezing, etc.), after which, we typically see clinical signs. There is a PCR test that can be done to confirm FVR that is very accurate (high sensitivity and specificity for you stats nerds).
Treatment - As with most diseases, there's good and bad news about treating feline herpes/FVR. The good news, the symptoms and secondary bacterial infection generally resolve quickly with a good prognosis. Bad news: it's herpes, and herpes is forever. In otherwise healthy cats, the disease will usually resolve on its own. In sick cats, it's important to find the underlying cause (fleas, it's almost always fleas). We typically give a broad-spectrum antibiotic to help eliminate secondary bacterial infections. I will use antiviral medications if there are more moderate-severe clinical signs or if the infection reoccurs. L-lysine is an amino acid used to help prevent future infections and is very cheap, and can be used with all cats in the household.
The distemper vaccine for cats (FVRCP) includes FVR. While it will not prevent the disease, it will help the immune system react more effectively. This is why your vet will recommend FVRCP vaccines for kittens every 1-3 years, even for indoor-only cats. Cats can live 20+ years; if exposed to herpes as a kitten, it may lay dormant until their immune system becomes compromised by another disease. I learned another nifty trick while doing relief work (shoutout to Care Animal Hospital). Giving the FVRCP vaccine intranasally may also help to stimulate a local immune response for cats sneezing like crazy due to FVR.
Get your cats vaccinated and on flea/tick/heartworm prevention, take them to the vet if they get sick, feed them Purina, Hills, or Royal Canin, and spay/neuter them at 5-6 months old. Bam, 92% of my job is done. Hopefully, the information in these blogs sticks with you forever, like herpes.
For more information, click on any of the links above (or for info on kittens, click here). For more information on feline herpes virus or other upper respiratory infections: Veterinary Partner URI
