Cats are now largely indoor pets, but they are still susceptible to several viral diseases that can cause significant illness or death. From common infections, such as feline herpesvirus, to more serious conditions, such as feline leukemia virus and feline immunodeficiency virus, understanding these diseases is crucial for effective prevention and management. Our Tamberly Animal Hospital team explores the various feline viral diseases.

Feline herpesvirus

Feline herpesvirus type 1, or feline viral rhinotracheitis, is a highly contagious virus that is one of the primary causes of upper respiratory infections in cats. This virus can spread like wildfire in crowded settings, such as animal shelters or catteries, and lead to lifelong infection.

The virus is transmitted by direct contact with infected cats, such as sneezing or contact with other respiratory secretions, and through touching contaminated objects and surfaces. Infected cats may develop:

  • Sneezing
  • Nasal and ocular discharge
  • Conjunctivitis
  • Fever
  • Lethargy
  • Appetite loss

These signs may seem to resolve, but they can flare up again if an affected cat is stressed or their immune system is compromised.

Herpesvirus treatment aims to alleviate symptoms and prevent secondary bacterial infections, which can generally be accomplished with supportive care, good nutrition, and a clean environment. Vaccination is key to preventing or minimizing herpesvirus infections. Keeping cats indoors, minimizing stress, and practicing good hygiene can also reduce transmission risk.

Feline calicivirus

Feline calicivirus is another common cause of respiratory infections in cats that, like feline herpesvirus, spreads through direct and indirect contact.

Cats infected with calicivirus typically display respiratory illness, including sneezing and nasal and ocular discharge. They can also develop a fever, lethargy, and oral ulcers that make eating and drinking painful. 

Treatment focuses on supportive care, including fluid and nutritional therapy, pain management if ulcers are present, and antibiotics for secondary bacterial infections. Most cats recover with appropriate care but can remain chronically infected for life.

Vaccination is essential for preventing calicivirus infections. Good hygiene practices, such as regular disinfection of litter boxes, bedding, and bowls, also help reduce the risk.

Feline panleukopenia virus 

Feline panleukopenia virus is a highly contagious viral disease that affects cats, especially kittens. This deadly virus spreads through contact with infected bodily fluids, feces, urine, or contaminated environments. The virus is particularly resilient and can survive in the environment for months.

Infected cats experience gastrointestinal (GI) issues and may develop:

  • Fever
  • Lethargy
  • Appetite loss
  • Vomiting
  • Diarrhea that is often bloody
  • Dehydration

Supportive care is essential and includes fluid therapy to combat dehydration, nutritional support, and medications to manage vomiting and diarrhea. The prognosis depends on infection severity and the effectiveness of supportive care. Kittens are particularly vulnerable, and mortality rates can be high, despite aggressive treatment.

Vaccination is highly effective in preventing panleukopenia. Vaccination protocols typically start when kittens are 6 to 8 weeks old, with booster vaccines administered at regular intervals. Good hygiene practices, such as disinfecting living areas and minimizing exposure to potentially contaminated environments, also help reduce infection risk.

Feline leukemia virus

Feline leukemia virus (FeLV) is a retrovirus that attacks the immune system, leaving cats susceptible to various infections and diseases, including anemia and cancer. The virus spreads through close contact with infected cats, primarily through mutual grooming or biting.

The immune system is weakened in FeLV-infected cats, so they are at risk for secondary infections and their overall health will likely be poor. Infected cats will be lethargic, lose weight, and their coat condition will be poor, and they may develop anemia, recurrent infections, or lymphoma.

FeLV has no cure, but supportive care can help manage symptoms and improve quality of life. An FeLV vaccination is available and should be part of a carefully tailored vaccination protocol. Keeping cats indoors and avoiding contact with unknown cats also reduce the risk.

Feline immunodeficiency virus

Feline immunodeficiency virus (FIV) also weakens the immune system and makes cats more susceptible to infections and other diseases. FIV is primarily transmitted through bite wounds during aggressive inter-cat fights and does not spread as easily as FeLV.

Common signs include weight loss, fever, lethargy, poor coat condition, gingivitis and stomatitis, and chronic respiratory issues, but they may not appear for years after the cat is infected.

FIV has no vaccine or cure, but supportive care can help manage symptoms and prolong life. The prognosis varies, depending on the cat’s overall health and the presence of concurrent diseases. Preventing exposure to FIV-infected cats by keeping your cat indoors and minimizing territorial conflicts is the best way to prevent transmission. 

Viral infections can cause serious, potentially fatal, illness, so keep your cat up to date on life-saving vaccinations by scheduling an appointment with our Tamberly Animal Hospital team.