Application of whole genome sequencing in a Clostridium perfringens diarrhea outbreak
An etiological analysis of a diarrhea outbreak attributed to C.perfringens was conducted.Anal swab and envi-ronmental smear samples were collected and subjected to fluorescence PCR detection of C.perfringens plc and cpe,as well as isolation and culture of C.perfringens before and after enrichment culture.The isolated colonies underwent fully automated bi-ochemical identification and time-of-flight mass spectrometry analysis.Whole genome sequencing of isolates identified as C.perfringens was performed to analyze the strain carrying virulence and resistance genes,and the genetic aggregation based on single nucleotide polymorphisms in the core genome for all isolates.The positivity rates for plc and cpe genes without bacterial enhancement were 46.15％(6/13)and 53.85％(7/13),respectively.The positivity rates for plc and cpe genes after 24 h anae-robic bacterial enhancement in BHI were 38.46％(5/13)and 53.85％(7/13).All ten isolated CP belonged to the F biotype,with virulence gene characteristics of plc+/cpb-/etx-/iA-/cpe+/cpb2+/netB-.The phylogenomic tree indicated that all ten case-patient isolates except P1 isolate(lineage 1)were closely related and clustered together in a single clade(lineage 2).Lineage 1 belonged to ST589 and carried the macrolide re-sistance gene erm(Q),whereas lineage 2 belonged to ST149 and carried the tetracycline resistance gene tetB(P).The outbreak was caused by type F C.perfringens,and most ca-ses were infected with a group of highly clonogenic cpe+col-onies.Whole genome sequencing technology can be applied to etiology analysis of C.perfringens outbreak events,and the enrichment culture and molecular screening methods for C.per-fringens based on anal swab samples should be further developed and applied.
万方数据
维普
