Comparison of Salmonella serotyping methods of slide agglutination and multiple fluorescence PCR serotyping kit

ObjectiveTo explore the applicability of the Salmonella serotyping kit in the surveillance of multiple intestinal pathogens, expand the laboratory's method for the serotyping of Salmonella, improve the laboratory capacity for the rapid and better response to diarrhea epidemic caused by Salmonella.

MethodsUsing multiple fluorescence PCR serotyping kit and traditional slide agglutination test, the serotyping of 95 Salmonella strains was conducted, which were isolated from multiple intestinal pathogens surveillance in Fengtai district of Beijing from 2013 to 2018, and the results were compared.

ResultsThe slide agglutination test result indicated that 95 strains of Salmonella belonged to 21 serotypes. The serotyping kit test indicated that 85 strains of Salmonella belonged to 17 serotypes, the remaining 10 strains were unspecified, including S. Goldcoast, S. London, S. Senftenberg, S. Thompson, S. Panama and S. Othmarsche. Among the 85 Salmonella strains, 83 shared same serotype in serotyping kit test and slide agglutination test, showing the consistent rate of 97.65%.

ConclusionTraditional laboratory slide agglutination method has a good performance in the serotyping of Salmonella. The serotyping kit test has very high consistency with slide agglutination test, but the identification of uncommon serotypes of Salmonella needs to be improved. The combination of the two methods would improve the efficiency and accuracy of Salmonella serotyping.