BMC veterinary research
Brucella abortus RB51 vaccination: a comprehensive systematic review of safety, efficacy, and global field outcomes (1990-2025)
By Dadar M, Arellano B, Gharekhani J and 4 others.
Abstract
Background
Brucella abortus strain RB51 is a live attenuated rough vaccine developed to overcome the serological interference of conventional smooth vaccines. Since replacing strain S19 in the United States (1996) and globally thereafter, RB51 has been promoted as a DIVA (Differentiating Infected from Vaccinated Animals) vaccine for brucellosis control in cattle and other livestock. However, conflicting reports on its safety, efficacy, and adverse effects have generated ongoing debate.
Methods
We conducted a systematic review following PRISMA guidelines. Six electronic databases (PubMed, Scopus, Web of Science, CAB Abstracts, Cochrane Library, SciELO) were searched from January 1990 to March 2025. Studies reporting original data on RB51 vaccination in animals or humans, including safety, efficacy, adverse events, or human health outcomes, were included. Due to extreme heterogeneity (I² > 94%), findings were synthesized narratively without meta-analysis.