Necrotizing fasciitis in captive juvenile Crocodylus porosus caused by Streptococcus agalactiae: An outbreak and review of the animal and human literature

We observed an outbreak of necrotizing fasciitis associated with Streptococcus agalactiae infection in a group of juvenile saltwater crocodiles (Crocodylus porosus). We undertook screening of crocodiles and the environment to clarify the source of the outbreak and evaluated the isolates cultured from post-mortem specimens with molecular methods to assess clonality and the presence of known group B streptococcal virulence determinants. The isolates were indistinguishable by pulsed-field gel electrophoresis. They were a typical serotype Ia strain with the C?-like protein gene, epsilon (or alp1), the mobile genetic elements IS 381 IS Sag1 and IS Sag2, and belonged to multi-locus sequence type (ST) 23. All of these characteristics suggest they were probably of human origin. We review the medical and veterinary literature relating to S. agalactiae necrotizing fasciitis, epidemiology and virulence determinants. � 2007 Cambridge University Press.