Table 3.

General characteristics of the B. melitensis Rev.1 vaccine in sheep (adapted from Blasco et al. (2016))

Advantages	Disadvantages	Comments
Proved efficacy in B. melitensis control/eradication programmes (France, Italy, Portugal, Spain). Effective against both B. melitensis and B. ovis. Safe in young replacements (males and females). Single dose affords useful protection for life. Biological quality control feasible (OIE accepted)	Highly abortifacient when used in pregnant ewes. Serological interference in classical serological tests (RBT, CFT), indirect and competitive ELISAs, fluorescence polarisation assay and other B. melitensis tests. Serological interference in HS B. ovis tests Virulent (low) for humans; streptomycin resistant	Safety issues minimised by avoiding use in mid‐pregnancy ewes by the conjunctival route. Serological interference minimised when applied exclusively to young replacement animals by the conjunctival route. Human Rev 1 infections can be diagnosed using simple standard serological tests; treatment requires regimes avoiding streptomycin