One-step differential detection of Salmonella enterica serovar Typhi, serovar Paratyphi A and other Salmonella spp. by using a quadruplex real-time PCR assay
Document Type
Article
Publication Date
4-1-2021
Abstract
Diseases caused by typhoidal and non-typhoidal Salmonella remain a considerable threat to both developed and developing countries. Based on the clinical symptoms and serological tests, it is sometimes difficult to differentiate the Salmonella enterica serovar Paratyphi A (S. enterica serovar Paratyphi A) from semvar Typhi (S. enterica serovar Typhi). In this study, we developed a quadruplex real-time polymerase chain reaction (PCR) assay with an internal amplification control (IAC), to simultaneously differentiate S. enterica serovar Paratyphi A from semvar Typhi and to detect other Salmonella serovars which cause salmonellosis in humans. This assay was evaluated on 155 salmonellae and non-salmonellae strains and demonstrated 100% specificity in species differentiation. Inclusion of an IAC did not affect the efficiency of the assay. Further evaluation using a blind test on spiked stool, blood and food specimens showed that the detection limit was at 10(3) -10(4) CFU/mL (or g) and a high PCR efficiency with different targets (R-2 > 0.99), except for S. enterica semvar Paratyphi A in blood. This assay has been applied to clinical specimens to detect the causative agents of gastrointestinal infections and has successfully identified 6 salmonellosis patients from the 50 diarrhoea patients. The quadruplex real-time PCR developed in this study could enhance the detection and differentiation of salmonellae. This assay could be applied to stools, blood and food based on the notable performance in the simulation tests and field evaluation.
Keywords
S. enterica serovar Typhi, S. enterica serovar Paratyphi A, Real-time PCR, Salmonellae detection
Divisions
fac_med,nanotechnology
Funders
International Fund received by the Principal Investigator [Grant No: IF004-2020].
Publication Title
Journal of Microbiological Methods
Volume
183
Publisher
Elsevier
Publisher Location
RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS