Assessment of the long-term effect of vaccination on transmission of infectious bovine rhinotracheitis virus in cattle herds hyperimmunized with glycoprotein E–deleted marker vaccine

Abstract

Objective—To assess long-term effects and risk factors for the efficacy of hyperimmunization protocols against infectious bovine rhinotracheitis (IBR) during a longitudinal field study of dairy and dairy-beef mixed farms. Animals—Approximately 7,700 cows from 72 farms. Procedures—Farms were assigned to 3 treatment groups (hyperimmunization groups [HIGs] 1 and 2, which were hyperimmunized with glycoprotein E [gE]–deleted marker vaccines, and a nonintervention group [NIG]). Cattle in HIG 1 were initially vaccinated with an attenuated vaccine, whereas cattle in HIG 2 were initially vaccinated with an inactivated-virus vaccine. Cattle in both HIGs received booster inoculations with inactivated-virus vaccines at 6-month intervals. The risk for gE seroconversion was compared among experimental groups via a shared frailty model with a piecewise constant baseline risk to correct for seasonal and secular effects. Results—Risk for gE seroconversion significantly decreased over time for the HIGs, compared with the NIG. Seasonal changes in the risk of gE seroconversion were detected, with a higher risk during winter periods, compared with grazing periods. No significant difference was detected between HIGs 1 and 2. The only significant risk factor was the number of buildings for cattle on a farm; the higher the number of buildings, the lower the risk for gE seroconversion. Prevalence of IBR decreased over time in both HIGs but remained constant or increased in the NIG. Conclusions and Clinical Relevance—Hyperimmunization via repeated administration of attenuated and inactivated-virus gE-deleted marker vaccines as well as inactivated-virus vaccines may provide a method for control of IBR.

Seroepidemiology of infectious bovine rhinotracheitis infection in unvaccinated cattle

“…The higher prevalence in reproductive disorder was probably due to natural service by infected bulls and artificial insemination with infected semen [ 1 , 2 , 15 ]. The respiratory form of prevalence was due to the frequent introduction of cattle from various parts of the country and intensive management practices of cattle [ 16 , 17 ].…”

Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): infectious bovine rhinotracheitis (IBR)

“…Parameter 3 -Field protection as reduced morbidity (as reduced susceptibility to infection and/or to disease) All vaccines licensed in Member States must satisfy the requirements of the IBR Monograph of the European Pharmacopoeia (OIE, 2017). Vaccines with DIVA properties are considered safe and efficacious based on data from experimental and field studies (European Commission, 2000;Dispas et al, 2004Dispas et al, , 2009EFSA, 2006;Makoschey et al, 2007;Ampe et al, 2012). Ultimately their efficacy in the field has been demonstrated by their incorporation into successful national eradication programmes (Commission Implementing Decision (EU) 2015/250).…”

“…Differentiating infected from vaccinating animals (DIVA) strategy. Marker (gE-deleted) vaccines, which are considered safe and efficacious based on both experimental and field data (European Commission, 2000;Dispas et al, 2004Dispas et al, , 2009EFSA, 2006;Makoschey et al, 2007;Ampe et al, 2012), are available and form the basis of a control strategy where initial prevalence is moderate to high. This approach, supplemented by biosecurity measures to address risks of introduction associated with breeding, trade and husbandry activities, can be used to reduce the initial prevalence, with remaining positive animals being culled when prevalence falls to 5%.…”

Effect of vaccination against bovine herpesvirus 1 with inactivated gE-negative marker vaccines on the health of dairy cattle herds

“…Continuous vaccination with live or inactivated gE-negative vaccines is reducing the circulation of the virus within a herd (Bosch et al, 1998;Mars et al, 2001;Vilmos et al, 2007;Jacevičius et al, 2008;Ampe et al, 2012;Raaperi et al, 2012a). By limiting the risk of having new BHV-1 gE-positive animals within the herd and by the gradual culling of field virus-infected animals, the herd may achieve IBR-free status (Makoschey and Bielsa, 2007).…”