IMPROVED ISOLATION OF SALMONELLAE FROM FECES USING A SEMISOLID RAPPAPORT-VASSILIADIS MEDIUM

A modified semisolid Rappaport-Vassiliadis (MSRV) enrichment medium was evaluated as an alternative to Rappaport-Vassiliadis (RV) broth for culture of salmonellae from faeces. Faeces from 1544 subjects were cultured using MSRV medium, selective agars, and RV and selenite F enrichment broths. Of the 183 strains of Salmonella spp. isolated, 88 % were recovered on MSRV medium, whilst only 59 % were recovered using RV broth. When MSRV medium was combined with direct culture and selenite enrichment, 98.9 % of salmonellae were recovered. The MSRV culture was found to be easy to read, and in most cases confirmation of organisms as Salmonella spp. could be made 24 hours after receipt of the faecal specimen.