Efficacy Test of a Prototype Real-Time PCR Kit Based on the sifA Gene for the Detection of Salmonella Typhi on Chicken Samples from Traditional Market at Jakarta

Abstract

Salmonella Typhi, the causative agent of typhoid fever, remains a significant concern for food safety and public health. Conventional culture-based detection methods are reliable but time-consuming, limiting their effectiveness for timely monitoring and control. Therefore, rapid, sensitive, and accurate molecular detection methods are needed. This study evaluated the performance of a prototype Real-Time PCR detection kit for identifying S. Typhi in chicken meat and compared its performance with selective culture and conventional PCR methods. Thirty chicken meat samples were collected from traditional markets across Jakarta. All samples were initially analysed using selective culture media, followed by DNA extraction from culture-positive isolates and molecular detection using conventional PCR and Real-Time PCR targeting the sifA gene (223 bp). The prototype kit was validated using positive controls derived from purified bacterial DNA (Ct = 10.55±1.00; Tm = 82.09±1.00°C) and artificially contaminated samples (Ct = 14.01±1.00; Tm = 82.32±1.00°C). Real-Time PCR demonstrated superior detection performance for S. Typhi compared with selective culture and conventional PCR. The prototype kit showed high specificity and sensitivity for detecting S. Typhi in chicken meat samples, including artificially contaminated samples. Overall, these findings demonstrate that the sifA-based Real-Time PCR prototype kit provides a rapid, sensitive, and reliable approach for detecting S. Typhi in chicken meat and has potential application in routine food safety monitoring.