Canine herpesvirus-1 (CHV-1) is presumed to be enzootic in the dog population and is associated with reproductive disorders and neonatal mortality. Abstract To determine the frequency of spontaneous canine herpesvirus-1 (CHV-1) reactivation and ocular viral shedding in latently infected dogs and the effect of topical ocular administration of cyclosporine.8 mature Beagles with experimentally induced latent CHV-1 infection.Following induction of primary ocular CHV-1 infection, the presence of reactivatable CHV-1 latency was confirmed by systemically administering prednisolone to the dogs. Although FHV TK and CHV TK have a level of identity of 31 and 35%, respectively, with HSV-1 TK, and a general amino acid similarity of ≈54% with HSV-1 TK, they do not recognize the same broad range of substrates as HSV-1 TK does. The immunoperoxidase monolayer assay was used for testing of CHV1 antibodies. When cells were coinfected with gE/Z and gI/Z, the molecular masses of gE and gI were increased from 76 to 94 kDa and from 40 to 55–62 kDa, respectively. Spread of the disease is controlled by not breeding dogs known to have it. Mean age for dogs included in the study was 4.2 years (95% CI 4.0-4.5), and there was no difference in age between seronegative dogs vs seropositive dogs.
Mean age for seronegative dogs was 4.7 yrs (95% CI 4.1-5.4) and for seropositive dogs 5.0 yrs (95% CI 4.7-5.4). Cyclophosphamide (200mg/m 2 ) was administered to mature dogs latently infected with CHV-1 to determine its potential to induce recurrent CHV-1 disease and viral shedding. No association was demonstrated when comparing CHV1 antibody titers to gender or reproductive parameters like previous matings, pregnancies, births or number of puppies born. Age, visit in foreign countries and clinic explained together 78% of the variation in antibody titer categories. The percentage of positive samples differed significantly between the four clinics (A 98%, B 58.5%, C 74.6%, D 89.5%). A reasonable explanation for this finding has not been established. No information about an ongoing outbreak of CHV1 infection was available.
In conclusion, this study strongly indicates that CHV1 infection is endemic in the dog population of Norway. Twenty-seven 10- to 16-week-old laboratory Beagles.