ObjectiveTo describe the characteristics of avian influenza virus contamination in farmers’ markets in Zengcheng district form January 2019 to June 2020, and to analyze the impact of the coronavirus disease 2019 (COVID-19) pandemic on contamination of the markets by avian influenza virus.
MethodsRandom sampling and testing of avian influenza virus nucleic acids were carried out for farmers’ markets in Zengcheng district. Influenza A virus positive samples were further detected for subtypes of H5, H7 and H9. SPSS 26.0 was used for statistical analysis of the data.
ResultsA total of 1 978 samples were tested and the overall positive rate was 31.24% (618/1 978), while H9 subtype accounted for 92.07% (569/618). The difference of the positive rates in 2019 and 2020 was not statistically significant (x2=0.052, P=0.082). Among different types of samples, the positive rate of samples collected from the inner wall of feather removal machines was the highest (44.08%), while the positive rate of samples collected from inner wall of freezers was the lowest (13.33%).
ConclusionsH9 was dominant subtype of avian influenza virus responsible for contamination of farmers’ markets in Zengcheng district. Samples collected from the sites with direct contact with live poultry were more likely to detect avian influenza virus. The positive rates of avian influenza virus before and after the COVID-19 pandemics showed no statistically significant difference. Strengthened regulatory management of the farmers’ markets is recommended.