Feline calicivirus (FCV) is a common respiratory pathogen of cats. It has a high mutation rate in its surface proteins. This affects the biologic properties of the virus. Understanding the genetic diversity of FCV is important for diagnosis of and protection against FCV infection. These investigators examined the genetics of FCV found in cats in Switzerland. Sixty-six separate isolates were characterized. These segregated into 52 strains. Genetic diversity did not seem to vary with geographic locale.
Interestingly, the majority of pedigreed cats were infected with a single lineage of FCV even though the cats were in different geographic locales and samples were collected from multiple veterinary practices.According to the investigators, “It could be hypothesized that pedigree cats represent a new environmental niche to which FCV might become adapted. The association with pedigree might be caused by a common route of transmission of FCV strains among pedigreecats in Switzerland, e.g. during cat exhibitions or within breeding catteries. FCV is a highly contagious pathogen and resistant to many disinfectants. An indirect transmission (without cat-to-cat contact) at cat exhibitions could take place if hygienic measures are suboptimal. Alternatively, kittens could have acquired the infection within a few breeding catteries and still carry the virus as adult cats since FCV can induce persistent, long-term infections.” Only two samples identified strains closely related to the vaccine strain F9. (MK)