The role of enterovirus 71 and coxsackievirus A strains in a large outbreak of hand, foot, and mouth disease in 2012 in Changsha, China

• Main Authors: Jing-Fang Chen, Ru-Sheng Zhang, Xin-Hua Ou, Fa-Ming Chen, Bian-Cheng Sun
• Format: Article
• Language: English
• Published: Elsevier 2014-11-01
• Series: International Journal of Infectious Diseases
• Subjects: Hand; foot; and mouth disease; Etiology; Enterovirus 71; Coxsackievirus A
• Online Access: http://www.sciencedirect.com/science/article/pii/S1201971214016099
• ISSN: 1201-9712; 1878-3511

Background: During 2012, Changsha experienced a large outbreak of hand, foot, and mouth disease (HFMD), resulting in 25 438 cases, including 42 severe cases and eight deaths. Methods: Seven hundred and forty-six clinical specimens were collected from hospital-based surveillance for HFMD in 2012. The detection and genotyping of enterovirus were performed by real-time RT-PCR and sequencing of the VP1 regions; phylogenetic analysis was performed based on the VP1 sequences. Results: A total of 545 (73.1%) enterovirus-positive samples were identified, with the most frequently presenting serotype being enterovirus 71 (EV-71; n = 364, 66.8%), followed by coxsackievirus A16 (CV-A16; n = 84, 15.4%), CV-A6 (n = 22, 4.0%), and CV-A10 (n = 19, 3.5%). Most of the affected patients were children aged ≤5 years (n = 524, 96.1%). EV-71 was the major pathogen in the severe and fatal cases (n = 22, 78.6%). Phylogenetic analysis of VP1 gene sequences showed the EV-71 isolates to belong to subgenotype C4a, and the CV-A16 isolates to belong to subgenotype B1. The Changsha CV-A6 and CV-A10 circulating strains were homologous to strains circulating in other areas of mainland China. Conclusions: Our results demonstrate that EV-71 was the primary causative agent responsible for the HFMD outbreak in Changsha in 2012, and the co-circulation of other coxsackievirus A strains posed a potential risk to public health.