Serotypes and Spa types of Erysipelothrix rhusiopathiae isolates from British pigs (1987 to 2015).

Erysipelothrix spp. cause a range of clinical signs in pigs and at least 28 different Erysipelothrix spp. serotypes have been identified. In this study, 128 isolates of Erysipelothrix spp. from pigs in Great Britain from 1987 to 2015 were characterised by serotyping and multiplex real time PCR assays targeting the surface protective antigen (Spa) and the main genotypes (Erysipelothrix rhusiopathiae, Erysipelothrix tonsillarum and Erysipelothrix spp. strain 2). All 128 British isolates were characterised as E. rhusiopathiae and were classified as serotypes 1a (n=21), 1b (n=17), 2 (n=75), 5 (n=2), 9 (n=2), 10 (n=2), 11 (n=4) and 15 (n=1), while four isolates were untypeable. All isolates were positive for the spa A gene. Serotypes 1a, 1b and 2 constituted 88.3% of the isolates; current serotype 2 based vaccines should protect against these isolates.