Dynamics of bovine herpesvirus type 1 infection in Estonian dairy herds with and without a control programme.
Bovine herpesvirus type 1 (BHV-1) is an important bovine pathogen, exacerbating poor health and the productivity of cattle. The aims of this study were to detect the efficacy of vaccination programmes in lowering the seroprevalence of BHV-1 gE within the dairy herd and to follow the dynamics of the infection in non-vaccinated herds with uninfected heifers. A two-year longitudinal study was carried out on seven herds that were vaccinated, and in five herds with uninfected heifers without applying a control programme. After the start of the vaccination programme, calves born remained free from the virus. However, in one herd, 7 per cent (95 per cent CI 2 to 18) of these animals showed antibodies to BHV-1 two years after the first vaccination. A decline in BHV-1 antibody prevalence was found in vaccinating herds. Among the five herds not under the control programme, one experienced active virus spread, although one herd experienced self-clearance of the virus. In the herds with high BHV-1 prevalence, vaccinating all cattle from three months of age twice a year with a commercial inactivated marker vaccine efficiently protected offspring from becoming infected, and lowered the prevalence of BHV-1 within the herd. A small proportion of herds may experience self-clearance of the virus.
Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Kreutzwaldi 62, Tartu, 51014, Estonia. Kerli.Raaperi@emu.ee
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Raaperi
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Aleksejev
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T
Orro
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Viltrop
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D016022:Case-Control Studies; D002417:Cattle; D003612:Dairying; D005260:Female; D007242:Herpesvirus 1, Bovine / Q000276:immunology*; D022283:Herpesvirus Vaccines / Q000276:immunology*; D007241:Infectious Bovine Rhinotracheitis / Q000453:epidemiology / Q000517:prevention & control*; D008137:Longitudinal Studies; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D014611:Vaccination / Q000662:veterinary*
D000914:Antibodies, Viral; D022283:Herpesvirus Vaccines