Selection of candidate strains for hand, foot and mouth disease vaccine against enterovirus 71

The study aimed to select candidate strains from Vietnam for the development of the hand, foot and mouth disease (HFMD) vaccine against enterovirus 71 (EV71). Annual EV71 virus surveillance data of Pasteur Institute in Ho Chi Minh city from 2003 to 2013 was used to predict evolutionary trends. One hundred VP1 sequences of Vietnam strains from the GenBank database were used to evaluate the identity of acid amin sequences and identify the consensus sequences at key epitopes. As a result, the subgenogroup B5 strain named B5-203P-2013 was selected. The strain was adapted on Vero cells by multiple passages and plaque isolated. The strain B5-203P-2013-P10.1 was selected as a candidate strain for the HFMD vaccine due to possessing genetic stability, hightiter of 108 TCID50/ml and cross-neutralising antibody responses against other subgenogroups B5, C4, C5.