The second installment of the Cat Virus Disease series is about Feline Calicivirus Infection.
【Feline Calicivirus Infection】
This infection is caused by Feline Calicivirus (FCV) and, along with Feline Herpesvirus and Feline Chlamydia, it contributes to upper respiratory infections, commonly referred to as ‘cat colds’. While FCV itself may not always manifest pathogenic symptoms, it has the ability to infect many animals, including the pet owner and other animals living in the same household, thus requiring caution.
＜Symptoms＞
1. Low-virulence strain:
– Stomatitis
– Eye discharge
– Nasal discharge
– Sneezing
– Loss of appetite
– Vesicles and ulcers on the tongue
Symptoms typically resolve within 2-3 weeks.
2. High-virulence strain:
– Fever
– Skin ulcers
– Edema of the head
– Liver lesions
– DIC (Disseminated Intravascular Coagulation)
– Multiple organ failure
The high-virulence strain is known to cause severe symptoms in adult cats, with a fatality rate of 33-50%.
Furthermore, even with low-virulence strains, symptoms may worsen due to secondary bacterial infections or co-infections, particularly in young kittens or cats with weakened immune systems.
＜Transmission routes＞
The virus is transmitted nasally or orally through the nasal discharge, eye discharge, or saliva of infected cats. Feline Calicivirus can establish a latent infection in the epithelial cells of the tonsils, turning the cat into a carrier, and may cause recurring symptoms when the cat’s immune balance is disrupted.
＜Diagnosis＞
While most cases are diagnosed based on clinical symptoms, PCR tests and antibody tests may be conducted to confirm the presence of Feline Calicivirus.
＜Treatment＞
There is no effective treatment for Feline Calicivirus itself. Supportive care is provided to alleviate the current symptoms, aiming for the cat to overcome the infection with its own strength and immune response.
Supportive care may include fluid therapy for dehydration, nutritional support, administration of non-steroidal anti-inflammatory drugs for pain and inflammation relief, and Interferon (IFN-ω).
Additionally, broad-spectrum antibiotics may be used to prevent secondary bacterial infections or co-infections.
＜Precautions＞
FCV is highly resistant in the environment and is said to remain infectious for about a month. Therefore, disinfect living spaces and dishes using 0.1% sodium hypochlorite.
＜Prevention＞
Like Feline Panleukopenia Virus, FCV can also be prevented through vaccination. Ensuring proper vaccination during kittenhood is crucial for prevention, though it does not guarantee complete protection against FCV infection. Maintaining a stress-free environment and providing immune-boosting supplements can also help prevent the onset of the infection.
