Like people, cats can be affected by viruses, which are infectious agents that can replicate only inside living cells. Certain feline diseases can seriously affect your cat and lead to lifelong issues. Our team at The Old 41 Animal Hospital explains the most common feline viral diseases and how to protect your cat. 

Common feline viral diseases 

1: Feline leukemia virus  

Feline leukemia virus (FeLV) is a contagious retrovirus (i.e., a group of RNA viruses that insert a DNA copy into the host cell and replicate.)

  • FeLV transmission — FeLV affects only cats, and cannot be transmitted to humans or other animals. The virus can be transmitted through saliva during mutual grooming, bite wounds, from mother to kitten in utero or through their milk, and through urine and feces. FeLV is most commonly spread in animal shelters, hoarding situations, or multi-cat homes that do not take proper prevention measures.
  • FeLV signs — Some cats may not show signs after FeLV exposure, and many cats resist infection and clear the virus on their own. However, cats who appear healthy after FeLV exposure can still spread the virus. An infected cat may not show for years any virus signs, which may include:
    • Pale gums
    • Weight loss
    • Persistent diarrhea 
    • Enlarged lymph nodes
    • Inflamed gums and mouth
    • Lethargy
    • Gastrointestinal problems
    • Neurological disorders
    • Respiratory problems
  • FeLV diagnosis —  Your veterinarian can diagnose FeLV with a simple blood test.
  • FeLV treatment — FeLV cannot be cured, and most infected cats will succumb to an FeLV-associated illness. However, many infected cats also enjoy a high quality of life for several years with regular veterinary care.
  • FeLV prevention— FeLV in cats can be prevented with vaccinations. The American Association of Feline Practitioners recommends that kittens receive two vaccinations, plus a booster at 12 months of age. 

2: Feline immunodeficiency virus 

Feline immunodeficiency virus (FIV) is similar to FeLV, but specifically targets the cat’s immune system and can cause immunodeficiency. 

  • FIV transmission — FIV is most commonly transmitted through bite wounds from an infected cat. Cats who share water bowls or groom with an FIV-infected cat are at low risk for contracting the virus. FIV can affect all cats, but is more commonly diagnosed in outdoor, unneutered males. 
  • FIV signs — Signs include lethargy, conjunctivitis, inflammation of the mouth and gums, weight loss, and fever, but often do not occur for years after diagnosis. 
  • FIV diagnosis — Diagnosis typically involves blood tests to detect the presence of viral antibodies. 
  • FIV treatment — While no FIV cure exists, supportive care and management of secondary infections can help improve the cat’s health and prolong their lifespan.
  • FIV prevention — Keep your cat indoors and avoid contact with cats who have not been FIV tested to reduce their chances of contracting an FIV infection. Regular preventive care exams will help your cat stay healthy overall.

3: Feline calicivirus in cats

Feline calicivirus (FCV) is a highly contagious virus that affects the cat’s mouth and respiratory system. 

  • FCV transmission —  FCV is highly contagious and can survive up to a week in the environment. The virus spreads through an infected cat’s nasal secretions, ocular discharge, and saliva. A cat who recovers can still become a carrier (i.e., they have the ability to infect other cats).
  • FCV signs — FCV signs may be seen two days to two weeks following the initial infection and can persist for more than six weeks. Signs in cats, which can range from mild to severe and include fever, oral ulcers, and pneumonia, depending on the viral strain, are similar to other upper respiratory infections.
  • FCV diagnosis — An FCV diagnosis is made based on your cat’s medical history, clinical signs, and potential FCV exposure history. 
  • FCV treatment — While most cats will recover with at-home support and treatment, including ensuring their nose and eyes are kept clean, some kittens or adult cats with severe signs may require hospitalization. 
  • FCV prevention — The FVRCP vaccine can safeguard your cat against FCV and other dangerous respiratory infections. Vaccinating your cat when they are young is the best prevention.

Our team is here to ensure your favorite feline is protected against these nasty viruses. If you still have questions, or to schedule your cat’s preventive care examination, contact The Old 41 Animal Hospital for an appointment.