Molecular epidemiology of human coxsackievirus A16 strains

Abstract

The hand, foot and mouth disease (HFMD) epidemics have mainly been caused by human enterovirus 71 and human coxsackievirus A16 (CA16), which circulated alternatively or together in the epidemic area. The aim of the present study was to provide guidance in the prevention and control of HFMD from CA16 infection. The molecular epidemiology of the human CA16 strains was investigated. Overall, 1,151 specimens (throat swabs) were collected from 1,151 patients with HFMD symptoms. The results of the homology comparison in the VP1 of CA16 strains showed that the CA16 strains belonged to the B1b subgenotype. The difference of the 6 CA16 strains analyzed showed that the most prominent strain was the A genotype, and the most close strains were the B1 gene subtype, particularly the B1b gene subtype. With regards to the amino acids, in addition to the A genotype, the differences of amino acids with other gene subtype was not significant. The present data suggest that more effective and highly targeted intervention mechanisms could be developed for the prevention and control of HFMD.

Keywords: Jiujiang region; foot and mouth disease; hand; human coxsackievirus A16; molecular epidemiology.

Figure 1.

Cases of EV71 and CA16 infection with hand, foot, and mouth disease detected in the Third People's Hospital of Jiujiang City (Jiangxi, China) between January and December 2012. EV71, enterovirus 71; CA16, coxsackievirus A16.

Figure 2.

Phylogenetic trees constructed from CA16-positive specimen VP1 nucleotide sequences by the neighbor-joining method with 1,000 bootstrap replicates using MEGA5. The tree was based on a 378-base pair CA16 VP1 sequence (2785–3162 nucleotide, reference U05876). •Strains obtained in the study. CA16, coxsackievirus A16.