Evaluation of staA , viaB and sopE genes in Salmonella detection using conventional polymerase chain reaction (PCR)

Typhoid fever is caused by the bacteria subspecies serovar Typhi (. Typhi) and remains a significant health problem in many developing countries. The lack of adequate diagnostic capabilities in these poor resource settings have contributed greatly in making typhoid fever endemic in these regions. Reliable and inexpensive diagnostic tests are needed to improve the management of this disease burden. This study evaluated the ability of and genes to detect spp. Conventional polymerase chain reaction (PCR) amplification of , and genes of was used to detect and differentiate between the three most prevalent spp. in Kenya (. Typhi, Typhimurium and Enteritidis). The primers (StaA-Forward / StaA-Reverse) and primers (vi-Forward / vi-Reverse) were found to be specific only for the different strains of . Typhi, producing PCR products of 585 bp and 540 bp respectively. No amplification was observed with Typhimurium, Enteritidis, . coli and . boydii bacterial strains. The primers (SopE-Forward / SopE-Reverse) was demonstrated to be specific for all spp. producing a 465 bp PCR product with no amplification observed with the . coli and . boydii bacterial strains. Conventional PCR using these and primers for detection of . Typhi shows great potential for diagnosis of typhoid fever however, further studies need to be carried out with actual food samples and human samples (blood, stool or saliva) to determine the effectiveness of this method in the detection of common Salmonella spp. in Kenya.