Survey of enterovirus infections from hand, foot and mouth disease outbreak in China, 2009

Abstract

Background: In China, a rapid expansion of Hand, foot, and mouth disease (HFMD) outbreaks has occurred since 2004 and HFMD has become an important issue for China. However, people are still only concerned with human enterovirus 71(HEV-71) and coxsackie virus A16 (CV-A16). Much of what is known about the other enterovirus infections relies on fractional evidence and old epidemic data, with little knowledge concerning their distribution. To alert potential threatens of the other enteroviruses, our study genetically characterized specimens from different regions of China and yielded novel information concerning the circulating and phylogenetic characteristics of enteroviral strains from HFMD cases.

Findings: A total of 301 clinical throat swabs were randomly obtained from patients suffering from HFMD from the southern, northern and central regions of China during outbreaks in 2009. 266 of 301 (88.4%) HFMD cases were found positive for HEV and seven genotypes, HEV-71, CV-A16, -B5, -A4, -A6, -A10, and -A12, were detected.

Conclusions: The HFMD pathogen compositions in the different regions of China were significantly different. HFMD epidemics might persist for a long time in China due to the multiple pathogen compositions, the enteroviral characteristic of recombination and co-infection, the ever-increasing travel and migration and the deficiency of effective vaccine. Our study deserves the attention on HFMD control and vaccine development.

Figure 1

Consensus phylogenetic tree constructed with human enterovirus (HEV)-71 (a) and coxsackie virus (CV)-A16 (b) sequences, including isolates from the present study (dots). The nucleotides correspond to the prototype BrCr strain at positions 2597-2900 for (a) and (b).