THE DISTRIBUTION OF SEROTYPES AND VIRULENCE – ASSOCIATED GENES OF STREPTOCOCCUS SUIS IN HUMANS

Mạnh Hùng Thân1,2,, Văn Nam Lê3
1 National Hospital of Tropical Diseases
2 University of Medicine and Pharmacy - Hanoi National University
3 103 Military Hospital

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Abstract

Background: Meningitis and septic shock are two of the most common symptoms caused by the bacteria Streptococcus suis (S. suis), which also has a high death rate. Serotypes and virulence genes of S. suis are associated with severity. Objectives: To investigate the distribution of serotypes and virulence-associated genes of S. suis in humans. Methods: A prospective study was to collect and analyze clinical data, serotypes, and virulent genotypes of S. suis. Results: The disease was most common in men (91.3%), and S. suis type 2 (92.5%). Most strains contained virulence genes mrp (98.75%), epf (97.5%), sly (96.25%), and salK/R (75%). 95% of the cases were caused by the mixture of the three virulence genes mrp+/epf+/sly+. Four virulent genes (mrp+/epf+/sly+/SalKR+) were found to be present in 72.5% of the specimens. There was no difference in virulence gene distribution among groups. Conclusion: The most prevalent serotype of S. suis in humans was type 2. Four major virulence genes included mrp, epf, sly, and salK/R. No association was found between the frequency of virulence genes and the severity.

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References

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