Epidemiological survey and genetic sequence analysis of a human case infected with avian influenza A(H9N2)virus in Loudi City
Objective To conduct an epidemiological survey and genetic sequence analysis on a case of human infection with avian influenza A(H9N2)virus in Loudi City so as to provide a basis for scientific prevention and control of avian influenza in future.Methods On February 10,2023,an epidemiological investigation was conducted among close and secondary close contacts of a patient diagnosed with avian influenza A(H9N2)virus infection as well as the nearby live poultry market in Loudi City,Hunan Province.In addition,the patient's as well as close and secondary close contacts'throat swab samples were collected for genetic sequence analysis.Results All the subjects detected presented negative nucleic acid testing results except the patient.Testing of chicken blood samples and environmental samples from the patient's residence and its neighborhood also showed negative results for avian influenza viruses,but H9N2 was detected in samples collected from the nearby live poultry market.Genetic sequence analysis revealed that the hemagglutinin(HA)gene sequence of the strains detected and H9N2 strains previously obtained from human infection in mainland China displayed homologies ranging from 83.6％to 98.5％,which were closest with ON856627/Fujiansiming/2021(H9N2)Human/HA,with the homology being 98.5％.The neuraminidase(NA)gene sequence of the strains detected and H9N2 strains previously obtained from human infection in mainland China displayed homologies ranging from 83.3％to 95.5％,which were closest with MT875139/A Szuhou/2019(H9N2)Human/NA,with the homology being 95.5％.Conclusion The patient's infection with avian influenza A(H9N2)virus is closely related to the existence of avian influenza A virus in the local live poultry market.In future,routine surveillance for influenza-like illnesses should be improved by increasing the sample size and sampling frequency.
avian influenza A(H9N2)human infection with H9N2live poultry marketgenetic sequencehemagglutininneuraminidase
万方数据
维普
