Etiology of paratyphoid A and B outbreaks

ObjectiveTo understand the molecular biological characteristics of the pathogens detected in the paratyphoid A and B outbreaks occurred in a school of Xinjiang Production and Construction Corps in 2018, and provide evidence for the identification of the outbreaks.

MethodsSeventeen strains were collected from patients in the hospital. The serological subtyping of 17 isolated strains was conducted. The antibiotic susceptibility test of the strains was done by using micro-broth dilution method. The pulsed-field gel electrophoresis (PFGE) patterns of the strains were analyzed with software BioNumerics 7.6.

ResultsAmong the 17 strains, 12 were paratyphoid A strains with antigen 1,2,12∶a∶-, and 5 were paratyphoid B strains with antigen 1,4,12∶b∶1,2. All the strains were sensitive to 14 antibiotics. Cluster analysis of PFGE patterns showed that there were two patterns and the similarity of the two patterns was 59.4%. The same serotype had the same pattern type.

ConclusionPFGE plays an important role in the investigation of typhoid and paratyphoid outbreaks.