Fig. 3From: Distribution of avian influenza viruses according to environmental surveillance during 2014–2018, ChinaProportions of H5N1, H5N6, H7N9, H9N2 AIVs and other virus subtypes during 2014–2018. The X axis represents different years, and the Y axis represents proportion of different subtypes AIVs (%). The proportion is defined as the number of different AIVs subtypes/number of total viruses (%). Abbreviations AIVs: avian influenza virusesBack to article page