Molecular Identification and Phylogenetic Analyses of Coxsackievirus A24v Causing an Outbreak of Acute Hemorrhagic Conjunctivitis in Jiangxi, China, in 2010 / 病毒学报

ABSTRACT

To identify the cause of an outbreak of acute hemorrhagic conjunctivitis (AHC) in Jiangxi (China) in 2010, 20 eye conjunctival swabs were first collected from AHC patients. Then, viruses were isola- ted and tested for human enterovirus 70, coxsackievirus A24 variant (CV-A24v) and adenovirus using the polymerase chain reaction. All CV-A24v isolates underwent sequencing of 3C and VP1 coding regions. Then, a phylogenetic tree was constructed for Jiangxi CV-A24v and worldwide CV-A24v based on,3C and VP1 regions, respectively. Ten out of 20 specimens were positive for CV-A24v, implying that the outbreak was caused by CV-A24v. The phylogenetic tree based on the 3C region showed that Jiangxi CV- A24v belonged to cluster 5 in genotype IV (GIV-C5) with strains isolated throughout the world after 2010, and were divided further into A and B lineages. Phylogenetic analyses of the VP1 region showed that all of the worldwide CV-A24v strains isolated after 2000 could be divided into five groups (1-5). Jiangxi CV-A24v was classified into group 5 and also divided further into A and B lineages upon analyses of the 3C region. These data suggested that CV-A24v causing AHC outbreaks in China in 2010 belonged to GIV-C3 and GIV-C5. At least two transmission lineages were circulated in Jiangxi in 2010. The classification of CV-A24v isolated after 2010 worldwide using the phylogenetic tree based on the VP1 region was almost consistent with that based on the 3C region and also had significant chronological clustering.