| Objective: To understand the pollution and distribution of avian influenza viruses in natural environment in live poultry market,poultry scale farms,poultry farms and poultry slaughtering plants in Jiangxi Province,and to master H5N1 and H7N9 AIV infection status in the occupational exposure population.Identify high risk factors for infection,and to provide scientific basis for the prevention and control of human avian influenza epidemic.Methods: A total of 4 counties were collected from the southern,central and northern regions of Jiangxi Province as a monitor county by multi-stage sampling method.The live poultry market,poultry scale farms,poultry backyard farmer,poultry scale farms and poultry slaughter and processing plants were selected as for monitor points.A total of 2390 samples of external environmental specimens such as drinking water,feces were collected.We used Real-time PCR to detect the influenza A virus.The positive specimens were further examined by specific primers for H5,H7 and H9 Subtype identification.2272 serum samples were collected from live poultry market,poultry scale farms and so on sites.The H5N1 and H7N9 AIV antibodies were detected by horse erythrocyte hemagglutination inhibition test(HAI).Results:(1)The total positive rate of avian influenza A virus was 24.44%(584/2390)in the 2390 environmental samples collected from 2011 to 2015,among which the highest positive rate was 37.5% in 2014.The positive rate of avian influenza virus in different years was statistically significant(c2 = 85.598,P = 0.000).In the four quarter,the highest positive rate was 35.16% in the fourth quarter and the lowest rate was 8.64% in the third quarter.The positive rate of avian influenza A virus was statistically significant(c2= 133.521,P = 0.000).(2)The positive rate of avian influenza virus in different monitoring sites was statistically significant(c2 = 451.904,P = 0.000).The live poultry market was 56.37%(363/644),poultry spare area was 2.53%(26/1028),poultry scale farms(households)was 19.02%(101/531)and the poultry slaughtering plants was 50.27%(94/187).The positive rate of live poultry market and poultry farms were significantly higher than that other two places(P <0.05).(3)Among 5 different types of environmental specimens,the highest positive rate was 31.11%(14/45)of poultry case board wiped specimens,followed by 29.17%(98/336)of cleaning poultry sewage,cage surface was 27.14%(255/936)and bird feces was 23.01%(139/604).The lowest positive rate of poultry drinking water was 16.63%(78/469).(P <0.05).The positive rate of different types of specimens was statistically significant(c2= 25.289,P = 0.000).The positive rate of cleaning poultry sewage and cage surface wipe specimens were significantly higher than the poultry drinking water(P <0.05).(4)The pollution situation of avian influenza virus in different areas and different places has its own characteristics.The southern region(64.41%)and poultry slaughter and processing plant(48.94%)are dominated by influenza A other types.The central region is dominated by H7 and its mixed type(76.27%).The northern region(74.02%)and live poultry market(64.74%)are dominated by H5,H9 and its mixed type.Poultry scale farms(households)are coexist influenza A other types(49.50%)and H5+H7 mixed type(37.62%),and the area of poultry farms is dominated by H9 subtype(50.00%).(5)A total of 2272 serum samples were collected from 2011 to 2015.No positive samples of H5N1 and H7N9 subtype avian influenza virus were detected.There were 2.86%(65/2272)serum titers of ≥40,and mainly from poultry backyard concentrated areas and slaughter and processing plant staff.Conclusion: There are widespread avian influenza virus pollution in the poultry related environment of Jiangxi Province,among which the live poultry market and the poultry slaughtering and processing plant are the places where the pollution is more serious.There were no H5N1 and H7N9 subtype avian influenza viruses in the occupational exposure population,but there was a risk that the H5,H7 and H9 subtype avian influenza viruses were infected in the environment.It is recommended to take targeted prevention and control measures,do a good job in key areas,key groups,key links prevention and control.According to the characteristics of influenza virus and prevention and control of the actual situation,we should choose live poultry market,poultry slaughter and processing plants as the focus area,strengthen the occupational exposure and non-occupational floating population monitor in key areas,and strengthen poultry farming,sales and circulation process to supervision,to provide a scientific basis for prevention and control of AIV outbreaks. |
PDF Full Text Request