What is feline calicivirus (FCV)?

Feline calicivirus(FCV) is a highly contagious disease caused by feline calicivirus infection. The virus can cause upper respiratory infections and a range of oral diseases in cats. In fact, FCV is responsible for more than 50% of respiratory infections in cats. The virus most commonly occurs in multi-cat environments, such as shelters, breeding grounds or pet stores. Cats of any age can become infected, but kittens are especially susceptible.

Feline calicivirus(FCV) belongs to the Caliciviridae family, the genus Calicivirus. The nucleic acid type is single-stranded RNA, and the virus has no envelope. The diameter of the virus particle is 37-40nm, and the 32 hollow capsid particles are icosahedral three-dimensional symmetry. The virus is resistant to lipid solvents such as ether, chloroform and deoxycholine salts.The virus remains stably active at pH 4-5 and becomes inactive at pH 3. The virus does not have hemagglutination. Only one serotype can grow on feline kidney cells, tongue cells, thymocytes and feline fetal lung cells. FCV is highly species-specific and essentially infects only felines such as domestic cats, tigers, African lions, and Amur tigers. There is no cross-species contamination, which means no transmission to dogs and humans.

Under natural conditions, FCV usually occurs in cats between 8 and 12 weeks of age. The main source of infection is sick cats and cats with viruses. Infected cats can excrete a large amount of virus with secretions and excretions in the acute phase, directly infecting susceptible cats. After treatment, the symptoms of poisoned cats can disappear, but the virus can be transmitted to the outside world for a long time.

After exposure to FCV, the incubation period is 2 to 14 days before symptoms appear. The virus may initially infect the lining of the back of the mouth. After the virus replicates there, it may spread to other organs through the blood. However, FCV preferentially infects the lining of the mouth and lung tissue. Most cats develop upper respiratory infections, and in more severe cases, the virus can enter the lungs and cause pneumonia.