Survival of an emerging foodborne pathogen: Group B Streptococcus (GBS) serotype III sequence type (ST) 283—under simulated partial cooking and gastric fluid conditions
Group B Streptococcus (GBS) was previously not known to be transmitted through food, but an outbreak investigation in Singapore in 2015 documented for the first time an association between GBS Type III Sequence Type 283 infection and consumption of raw fish dishes. As very little is known about the survival of GBS during heat treatment and the stomach transit, its survival under simulated conditions was studied, in comparison with that of Escherichia coli O157:H7 and Listeria monocytogenes. The mean D-values of four GBS strains ranging from 0.72 to 0.88 min in neutral pH tryptone soy broth at 56.4 °C and 0.44–1.43 min at pH 2.35 at 37 °C in simulated gastric fluid, were significantly lower (p < 0.05) than those of E. coli O157:H7 and L. monocytogenes. This study suggests possible factors other than acid or heat resistance of GBS to be instrumental to its pathogenicity.
KeywordsGroup B Streptococcus Foodborne GBS Emerging foodborne pathogen Heat resistance Acid resistance
This study was jointly supported by the National University of Singapore (NUS) and the National Environment Agency (NEA), Singapore in 2017 and by the Korea National University of Transportation in 2018. We would like to thank Associate Professor Ng Lee Ching and Dr Ramona Alikiiteaga Gutiérrez of the Environmental Health Institute of the National Environment Agency for the permission on the use of GBS strains and the critical reading of the manuscript.
Compliance with ethical standards
Conflict of interest
The authors declare no conflict of interest.
Human and animal rights
This article does not contain any studies with human or animal subjects performed by the any of the authors.
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