Avian influenza virus in external environment in Akesu, Xinjiang, 2017–2020

  Objective  To understand the distribution of avian influenza virus in external environment in Akesu of Xinjiang and provide evidence for the prevention and control of human infection with avian Influenza virus in Akesu.

  Methods  Real time fluorescent quantitative RT-PCR was used to test the external environment samples in Akesu for the detection of avian influenza, and influenza A virus positive samples were further detected for H5, H7 and H9 subtypes. Software Excel and SPSS 25.0 were used to analyze the differences in distribution of avian influenza virus in different years, seasons, samples and surveillance sites.

  Results  A total of 580 samples were collected in Akesu from 2017 to 2020, and the positive rate of influenza A virus was 34.14%, the positive rate of H9 subtype was 94.95%, H5 subtype was 1.51%, and H5 + H9 mixed subtype was 3.54%, but H7 subtype was not detected. The annual positive rate of avian influenza virus in the external environment reached peak in October (62.50%). Among the six types of samples, the positive rate of poultry drinking water was highest (48.28%), and the positive rate of sewage in poultry markets was lowest (22.08%). The environment of the live poultry markets was contaminated by H9 and H5 subtypes of avian influenza virus.

  Conclusion  The surveillance results showed that the positive rate of avian influenza virus in the external environment of Akesu was high, mainly H9 subtype virus, and less H5 subtype virus. It is necessary to strengthen the surveillance for avian influenza virus in the external environment to understand the distribution of the virus in time and discover new subtypes of viruses for the early warning, prevention and control of human infection with avian influenza virus in Akesu.