How can we diagnose, treat, and deal with feline herpes? A prevalent virus in cats, the feline herpesvirus or FHV-1 is common, as 97% of pet cats are exposed to this virus and 80% have a lifelong infection. Understanding FHV-1 is important, and will help you care for your cat.

What is cat herpes, what are the symptoms, and how can it be treated? In this guide we go over cat herpes, and cat herpes symptoms, explaining everything you need to know.

What Is Cat Herpes?

The feline herpesvirus infection, called feline viral rhinotracheitis (FVR), is caused by the feline herpesvirus type-1, or FHV-1. This virus is species-specific and only causes infections in cats. It can affect cats regardless of age and is a major cause of respiratory disease in cats. It commonly causes inflammation around the eyes, especially the lining of the lids.

What Are the Symptoms of Cat Herpes?

Upper Respiratory Infection – an acute URI (Upper Respiratory Infection) is the most common sign of FHV infection. Other signs include sneezing, nasal and ocular discharge, salivation, lack of appetite, lethargy, fever, and coughing. This may last for days and up to a few weeks, with symptoms lasting around 3 weeks.

Keratitis – one uncommon manifestation of chronic cat herpes infection is the inflammation of the cornea. While keratitis can be caused by many different things, the inflammation caused by FHV will appear as multiple small branching corneal ulcers, also called dendritic keratitis.

Herpes Dermatitis – this rare manifestation of long-term cat herpes symptoms is skin inflammation and the formation of ulcers. This might happen around the nose and mouth, and even the front legs.

What Are the Causes?

Feline herpes attacks the nose, mouth, tonsils, lining of the eyes, and cornea. As the virus replicates, it can spread through fluid secretions and direct contact. When the virus is not treated, it can infiltrate the bones around the nose and mouth, causing long-term damage.

How Is Infection Diagnosed?

A veterinarian who believes your cat has contacted FHV-1 will administer a PCR (polymerase chain reaction) test, conducted by swabbing the mouth, and the eyes, or taking skin biopsies. However, the PCR test alone cannot differentiate from active or chronic versions of the infection. Feline herpes might also activate other underlying illnesses and issues, such as cat fever.

If your pet was infected by another sick cat, is vaccinated for feline herpes, or is a carrier of the virus, the test can show up positive. Diagnoses are made based on a complete physical exam, present symptoms, and your pet’s medical history.

Cat Herpes Treatment

Domestic cats with cat herpes symptoms are treated symptomatically. Treatment is based on specific clinical signs and problems that your cat is showing, determined by your cat’s veterinarian.

Your vet may treat infection of the eyes with topical eye medications, especially if your cat has corneal ulcers. Cats with chronic herpes or FVR conjunctivitis infections may need antiviral treatments, which can be applied orally.

Some cats respond to a specific amino acid called L-lysine, which helps reduce the severity of herpes and decreases infectious spread. Your veterinarian will recommend a specific dose and show you how to re-apply the medication.

The standard dosage of lysine for cats is 400mg once a day. You can mix a small amount of food with the medication, and your veterinarian may recommend a higher dosage or more frequent dosages. Lysine is available as crushable tablets, chewable tables, pastes, gels, or powders, and many veterinarians keep it stocked in their clinics.

If your cat has nasal or airway congestion, your veterinarian may recommend the use of a humidifier or taking the cat into a steamy bathroom for up to 15 minutes, several times a day. Cats with a respiratory infection will have a decreased sense of smell and a lessened appetite. By providing strong-smelling canned food, you may help their appetite return. Your veterinarian may also prescribe an appetite stimulant.

If there are signs of depression, dehydration, or other severe cases of the illness, your cat’s veterinarian may recommend hospitalization and more aggressive treatments, including IVs.

Recovery and Management of Cat Herpes

When diagnosed and treated early, most cat herpes recovery happens within 10-14 days with medication and supportive care. In the most severe cases, such as kittens and immunosuppressed cats, cat herpes can cause extreme symptoms and result in death.

Prolonged cat herpes of the affected areas can also result in physical damage and scarring of the face. This can lead to chronic nasal disease, pneumonia, and flares of infection.

How Long Is a Cat Infectious After Getting the Infection?

Any cat infected with FVR becomes a carrier. Cats with feline herpes will show symptoms of the disease within two to five days, which is the incubation period. Your cat can infect other cats during this period, and once symptoms appear the infection will last for up to 20 days.

Most carriers will be latent, and the virus can survive in its inactive form within their bodies. Stress or illness can reactivate the virus, which will again cause the cat to be infectious. The cat may show symptoms of respiratory infections, however not all reactivated cats will immediately show symptoms.

Vaccination Against Cat Herpes

Vaccination is important for all cats and is something your veterinarian will recommend when adopting a kitten or bringing a new cat into your home. It is recommended that your kitten receive two to three injections around 8 weeks old, with a booster at one year and further vaccines every one to three years.

Vaccination won’t prevent infection but will greatly reduce the severity of the disease and its symptoms. There is only one strain of FHV, which means that vaccinations don’t have to fight against different strains.

Vaccination Against Cat Herpes

Conclusion

It’s important to give your cat regular veterinary cat check-ups, get them their vaccines, and stay vigilant about their contact with other cats. Cat herpes can be a real problem, especially for younger cats, and your veterinarian can give you important advice on how to handle cat herpes and other infectious diseases.

Veterinarians like those at Paoli Vetcare have dedicated their lives to the diagnosis and treatment of feline diseases. Always contact your local veterinarian when you need more information about your pets, and at the first sign of any illness or problems, make an appointment!

FAQ

Are Other Cats in the Household at Risk of Infection?

Cats with acute FVR infections can infect other cats during their incubation period. While they develop symptoms it’s important to keep them away from other cats, as carrier cats can be infective for the rest of their lives.

The risk of infection increases in unvaccinated cats, especially those with chronic or underlying problems. Adult cats who are vaccinated may only develop one instance of the disease in their lives, and affected cats should be isolated to avoid further spread of the disease and minimize transmission.

Is My Family at Risk?

Upper respiratory infections and symptoms caused by cat herpes are only infectious to other cats. However, these infectious can be complicated by other bacterial infections, which can become contagious.

Following good hygiene practices and keeping your home clean, you can minimize the chance of contracting illnesses from your cat and from spreading diseases. Talk to your family physician and your cat’s veterinarian to learn more.

How Long Do Cats With Cat Herpes Live?

Cats that contract feline herpes remain carriers for life, and any chronic carrier can have recurrent active infections. These flare-ups are caused by stress or other underlying diseases and can be treated like other infections. By managing the frequency of their flare-ups, and stressors, keeping them up on vaccines, and using medications as directed by their veterinarian, cats with feline herpes can live a normal lifespan.

Your veterinarian may prescribe medications such as Famciclovir, an antiviral medication that can control the feline herpes virus (FHV-1). While its use is considered off-label, it has been proven to help cats manage feline herpes.

Any medication use should be given the okay by your cat’s veterinarian. Because there are medications that can interact and interfere with one another, it’s important to always check with your cat’s veterinarian first before administering any medication yourself.

Which Cats Are Most at Risk for Infection?

While all cats can be infected, infections are more severe in younger or immunosuppressed cats. Kittens can be born carrying the virus, and these symptoms may be very serious.

How Long Can the Virus Live In the Environment?

When an environment is contaminated, the virus can survive on any material as long as it remains moist. The secretions typically dry up in a short period, but viral particles can live on any skin surface. Since it’s spread by fluids, cat drooling can cause the virus to live on the surface of household items. Contaminated items like food and water bowls, toys, litter boxes, blankets, and furniture can be infectious for up to 18 hours.

What Should I Do if I Think My Cat Has Herpes?

If your cat is experiencing any of the symptoms listed above, contact your veterinarian right away. Your cat’s vet can help identify treatment options, and tell you if your cat needs nursing or immediate hospitalization.

Dr. Erin Downes VMD

Dr. Erin Downes graduated valedictorian from the University of Pennsylvania School of Veterinary Medicine in 1992. She and her husband, Dr. Jay Rowan are the owners of Paoli Vetcare | Main Line Vet & Animal Hospital.