Molecular Identification and Analysis of Human Enteroviruses Isolated from Healthy Children in Shenzhen, China from 2010 to 2011

Objective: To determine the prevalence and distribution of human enteroviruses (HEVs) among healthy children in Shenzhen, China. Method: Clinical specimens were obtained from 320 healthy children under 5 years old in Shenzhen, China from 2010 to 2011. The specimens were evaluated using real-time PCR and cell cultures. The positive specimens were further tested using reverse transcription-seminested PCR (RT-snPCR). Molecular typing and phylogenetic analysis were based on the sequence determined. Results: Among the 320 samples, 34 were tested positive for HEVs (10.6%) and 22 different serotypes were identified using RT-snPCR. PV1 and PV2 were also detected. The predominant serotype observed was EV71 (17.6%), followed by CV-B4 (14.7%). HEV-B was detected most frequently, with an overall prevalence of 47.1%. HEV-A and HEV-C were found in 32.3% and 20.6% of the samples, respectively. No HEV-D was identified. Molecular phylogeny indicated that all EV71 strains were of C4 genotype. Conclusion: Although a variety of HEVs was detected in healthy children, HEV-B was relatively more prevalent than other HEV species. Considering HEV-A is more prevalent than HEV-B among patients with hand-foot-mouth disease, additional long-term surveillance of HEV is warranted in both asymptomatic and symptomatic populations.