Use of RapidChekReg. SELECTTMSalmonella to detect shedding of live attenuated Salmonella enterica serovar Typhi vaccine strains.

摘要

Identification of individuals shedding Salmonella enterica serovar Typhi in stool is imperative during clinical trial safety evaluations. Recovery of live attenuated S. Typhi vaccine strains can be difficult because the mutations necessary for safety in humans often compromise survival in stringent selective enrichment media. RapidChekReg. SELECTTMSalmonella is a highly sensitive detection method for S. enterica species which utilizes a bacteriophage cocktail designed to reduce the growth of competitor microbes in mildly selective enrichment medium. Detection of Salmonella is enhanced by means of a Salmonella-specific antibody strip targeted to lipopolysaccharide. The RapidChekReg. SELECTTMSalmonella method was compared to conventional enrichment and plating methods to determine the most sensitive method for detecting attenuated S. Typhi strains in human stool samples. Although traditional enrichment strategies were more sensitive to the presence of wild-type S. Typhi, RapidChekReg. SELECTTMSalmonella was superior at detecting attenuated strains of S. Typhi. Strains containing a wide variety of attenuating mutations were detected with equal sensitivity as the wild type by RapidChekReg. SELECTTMSalmonella. The presence of Vi capsule or mutations which affected O-antigen synthesis ( Deltapmi, DeltagalE) did not decrease the sensitivity of the RapidChekReg. SELECTTMSalmonella assay