Mechanisms for persistence of acute and chronic feline calicivirus infections in the face of vaccination.
The study was concerned with possible reasons for the persistence of both acute and chronic feline calicivirus (FCV)-induced disease and sustained oral carriage in the field in the face of routine FCV immunization. It was concluded from this study that: 1) the original FCV-F9 strain, which is the basis of most live vaccines, still generates cross-reactive antibodies against almost all field strains in California, 2) vaccine strains derived from FCV-F9 may not be as broadly cross-protective as the parent strain, 3) whole inactivated FCV-2280 vaccine evokes high virus neutralizing antibody titers with an equally broad spectrum of cross-reactivity as FCV-F9, 4) all vaccine strains of FCV cause acute disease signs and protracted oral shedding when administered orally, 5) strains isolated from the mouth five to ten weeks following oral inoculation can differ from parental virus, usually appearing more vaccine resistant, 6) cats previously infected with field or vaccine strains develop much less severe acute illness when subsequently infected with heterologous FCV strains but are not protected against the chronic carrier state. Therefore, the persistence of FCV in the field cannot be explained solely by the emergence of vaccine resistant strains and vaccine virus itself may contribute to both acute and chronic infection and disease.
Pedersen
N C
NC
Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis 95616, USA.
Hawkins
K F
KF
D000208:Acute Disease; D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis; D000940:Antigenic Variation; D017250:Caliciviridae Infections / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary* / Q000821:virology; D017927:Calicivirus, Feline / Q000145:classification / Q000276:immunology* / Q000472:pathogenicity; D002140:California; D002353:Carrier State / Q000276:immunology / Q000662:veterinary; D002371:Cat Diseases / Q000276:immunology* / Q000517:prevention & control / Q000821:virology; D002415:Cats; D002908:Chronic Disease; D003429:Cross Reactions; D007106:Immune Sera / Q000276:immunology; D012463:Saliva / Q000821:virology; D012703:Serotyping / Q000662:veterinary; D013047:Specific Pathogen-Free Organisms; D014611:Vaccination / Q000662:veterinary*; D014765:Viral Vaccines; D014774:Virulence; D017201:Virus Shedding
D000914:Antibodies, Viral; D007106:Immune Sera; D014765:Viral Vaccines