title: Systematic review and meta-analysis of the effectiveness of commercially available vaccines against bovine herpesvirus, bovine viral diarrhea virus, bovine respiratory syncytial virus, and parainfluenza type 3 virus for mitigation of bovine respiratory disease complex in cattle.
abstract: OBJECTIVE
  To evaluate and analyze data from controlled studies on the effectiveness of vaccinating cattle with commercially available viral antigen vaccines for mitigation of the effects of bovine respiratory disease complex (BRDC).
  
  
  METHODS
  Systematic review and meta-analysis.
  
  
  METHODS
  31 studies comprising 88 trials.
  
  
  METHODS
  Studies that reported the effectiveness of commercially available bovine herpesvirus-1 (BHV-1), bovine viral diarrhea virus (BVDV), bovine respiratory syncytial virus (BRSV), and parainfluenza type 3 virus (PI3) vaccines for protection of cattle against BRDC or its components were included in the analysis. Studies or trials were categorized as natural exposure or experimental challenge and were further divided by the viral antigen evaluated and vaccine type (modified-live virus [MLV] or inactivated vaccine). Meta-analysis was performed; summary Mantel-Haenszel risk ratios were determined, and Forest plots were generated.
  
  
  RESULTS
  In natural exposure trials, beef calves vaccinated with various antigen combinations had a significantly lower BRDC morbidity risk than did nonvaccinated control calves. In trials evaluating BHV-1 and MLV BVDV vaccines in experimental challenge models, vaccinated calves had a lower BRDC morbidity risk than did control calves; however, in experimental challenge trials evaluating MLV BRSV and PI3 vaccines, no significant difference in morbidity or mortality risk was found between vaccinated and control calves.
  
  
  CONCLUSIONS
  Estimating clinical efficacy from results of experimental challenge studies requires caution because these models differ substantially from those involving natural exposure. The literature provides data but does not provide sufficiently strong evidence to guide definitive recommendations for determining which virus components are necessary to include in a vaccination program for prevention or mitigation of BRDC in cattle.
authors.affiliation: Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506.
authors.forename: Miles E
authors.initials: ME
authors.lastname: Theurer
authors.forename: Robert L
authors.initials: RL
authors.lastname: Larson
authors.forename: Brad J
authors.initials: BJ
authors.lastname: White
mesh_terms: D000818:Animals; D048090:Bovine Respiratory Disease Complex / Q000517:prevention & control* / Q000821:virology; D002417:Cattle; D007242:Herpesvirus 1, Bovine / Q000276:immunology*; D012328:RNA Viruses / Q000276:immunology*; D014765:Viral Vaccines / Q000276:immunology*; D014780:Viruses / Q000145:classification
chemical_list: D014765:Viral Vaccines