Research on spatiotemporal spread of avian influenza A(H7N9) virus based on discrete geographic information / 中华流行病学杂志

ABSTRACT

Objective To establish a dynamic spatiotemporal spread modes of influenza A(H7N9) virus by using discrete geographic information and explore the spatiotemporal transmission of the virus.Methods The gene sequences of H7N9 virus isolated from human in China,which were available from Global Initiative on Sharing Avian Influenza Data (GISAID),were used in alignment by using software BioEdit 7.0.Spatiotcmporal spread model of H7N9 virus was established in a Bayesian statistical framework by using software BEAST 1.8.2.The symmetric substitution model and Bayesian stochastic search variable selection (BSSVS) were used to infer and verify the historical transmission route of H7N9 virus.Finally the spatiotemporal transmission route was presented by Google Earth software.Results The transmission of avian influenza A (H7N9) virus originated in Shanghai and Hangzhou,and can be dated back to October 2012.In March and April 2013,it began to spread to the neighboring provinces.The transmission speed up in August and September and affected more than ten geographic positions within 3 months.Conclusion Based on gene sequences and spatial geographic information,the transmission route of H7N9 virus was traced,which would support the avian influenza prevention and control as well as avian influenza virus tracing.