Evaluation of two assays, MSRV and RV, for the isolation of Salmonella spp. from wastewater samples and broiler chickens.

Abstract

The Rappaport Vassiliadis (RV) and the Modified Semi-solid Rappaport Vassiliadis (MSRV) methods were evaluated in 130 municipal wastewater samples and 30 flocks of broilers. Analysis of the results showed that 71 Salmonella serotypes were isolated in wastewater samples. The positivity of the MSRV method was 33% and of the RV method, 45%. The sensitivity was 95% and 83% with the MSRV and RV, respectively. The concordance between the two methods was 89% (k = 0785). One hundred serotypes were isolated from broiler internal organs and 50 from intestinal samples. For internal organs, the positivity of MSRV was 56% and of RV, 45%. For intestinal samples, the respective percentages were 28 and 22. For internal organs, the sensitivity was 100% with MSRV and 81% with RV, whereas for intestinal samples, the sensitivity was 100% with MSRV and 80% with RV. The specificity was 100% in all cases. The concordance between the two methods was 89% (k = 0790) for internal organs and 94% (k = 0851) for intestinal samples.