Fig. 1

Geographical distributions of the nucleic acid positivity rates of influenza A, H5, H7 and H9 subtypes. a–d indicates the nucleic acid positivity rates of influenza A, H5, H7 and H9 subtypes on average in 31 PMA during 2014–2018, respectively. Different colours represent the corresponding range of positivity rates. Abbreviations: AH, Anhui; BJ, Beijing; CQ, Chongqing; FJ, Fujian; GD, Guangdong; GS, Gansu; GX, Guangxi; GZ, Guizhou; HA, Henan; HB, Hubei; HE, Hebei; HLJ, Heilongjiang; HN, Hunan; HaN, Hainan; JL, Jilin; JS, Jiangsu; JX, Jiangxi; LN, Liaoning; NM, Inner Mongolia; NX, Ningxia; QH, Qinghai; SC, Sichuan; SD, Shandong; SH, Shanghai; SX, Shanxi; SN, Shaanxi; TJ, Tianjin; XJ, Xinjiang; XZ, Tibet; YN, Yunnan; ZJ, Zhejiang. PAM: Provinces, municipalities and autonomous regions