Cases of erysipelas have increased considerably in 2001–2002. Diagnosis of erysipelas is typically confirmed by culture and in a limited number of cases the isolates are serotyped. Reagents for serotyping are limited and are available only at National Veterinary Service Laboratory (NVSL). In this study, we utilize pulsed-field gel electrophoresis (PFGE) to differentiate genotypes and compare archived and recent isolates. Seventy-three erysipelas field isolates (58 recent, 15 historical) and four live vaccine strains were genetically characterized. Fortysix isolates were found to belong to genotype 1A(I), three were genotype 1A(III), each one was genotype 1A(IV), 1A(V), 1A(VI), and two isolates were designated as 1A(VII). Nine different genotypes were identified among the serotype 1b isolates [1B(I-IX)]. Within serotype 2, three genotypes were identified: 2A, 2B, and 2C. The four vaccine strains tested in this study belong to the genotype group 1A(II), closely related to genotype 1A. The vaccine strains and the most common field isolates genotype 1A(I) shared 78.6% identity based on PFGE pattern.
Iowa State University
Opriessnig, T.; Hoffman, Lorraine J.; Halbur, Patrick G.; Harris, D.L. Hank; and Gaul, S. B., "Molecular Characterization of Recent and Archived Erysipelothrix rhusiopathiae Isolates" (2003). Swine Research Report, 2002. 27.