Systematic review of vaccine efficacy against Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni in North American cattle
Bovine respiratory disease (BRD) continues to greatly affect beef, dairy, and veal production systems. Vaccination against the bacteria involved is common, yet questions remain regarding efficacy. The purpose of this review was to evaluate the evidence for effects of vaccinating United States or Canadian beef, dairy, or veal calves for Mannheimia haemolytica, Pasteurella multocida, or Histophilus somni on BRD-related morbidity, mortality, or postmortem lung lesions. Comprehensive searches were performed of MEDLINE, EMBASE, and CAB Abstracts via OVID. The Bovine Practitioner and references of relevant systematic reviews were searched by hand. Major commercial vaccine producers were queried for additional product information.
Peer-reviewed, published after 1979, full text available in English, performed in the US/Canada, control group included, sufficient evidence of randomization/blinding, and correct statistical methods were essential criteria for inclusion in the review. Five studies met the criteria. Of them, 1 investigated a H. somni and M. haemolytica vaccine in feeder calves, 1 studied M. haemolytica vaccination in feeder calves, 1 evaluated a different commercially available M. haemolytica vaccine and 1 experimental M. haemolytica vaccine in young Holstein calves, and 1 investigated multiple vaccines for P. multocida or M. haemolytica or combinations thereof in nursing beef calves. There are too few repeated studies on comparable populations to support further analysis of BRD bacterial vaccine efficacy in North American cattle.