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@#Objective To analyze genetic characteristics of hemagglutinin( HA) gene of H9N2 avian influenza viruses( AIVs) circulating in Anhui Province from 2013 to 2018． Methods All H9N2 positive samples tested by real－time polymerase chain reaction( PCＲ) were inoculated into specific patho- gen free ( SPF) chicken eggs for isolation and purification． Viral ＲNA was reversely transcribed into cD- NA and then amplified with gene specific primers． PCＲ products were sequenced and the gene sequences were analyzed using molecular and bioinformatics software． The DATAMONKEY online server was conducted to analyze selection pressure，and protein structure homology modelling was computed by the SWISS－MODEL server． Ｒesults 33 H9N2 AIVs isolated from live poultry markets belonged to h9．4．2．5 in the phylogenetic tree． The receptor binding sites of HA gene at 183，226 and 227 position were mutated into N，L and M，respectively． Meanwhile 189 and 190 sites presented with genetic polymorphism． Since 2015，all H9N2 viruses in this study carried 6 potential N－linked glycosylation sites． It was found that po- sition 160 of HA gene was subjected greater positive selection pressure，presented 7 spatial conformations at least． Conclusions The H9N2 viruses isolated from live poultry markets in Anhui Province possess the molecular characteristics of infecting mammals and the ability of antigenic drift，so we need to pay more attention to the genetic characteristics of the viruses．
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We analyzed epidemiological and clinical characteristics of the case of human infected with avian influenza (H5N6) in Anhui Province and provided evidences for drawing up the prevention and control measures.We did an epidemiolog ical investigation on the case,close contacts and infection source of the infected case;relevant specimens were collected and tested in laboratories.The data gathered were analyzed with descriptive epidemiology method.The first case of human infected with avian influenza (H5N6) in Anhui was a single case and did not showed signs of human-to-human transmission.The early clinical manifestations and signs was lack of specificity.This case had definite contact with sick/dead poultry one week before the onset of the disease.Two environmental specimen of live poultry market which was the source of sick/dead poultry had been detected and the results were H5N6 positive.This case was a local infection case and contacting with sick/dead poultry was the source of infection,while there was no evidence of human to human transmission.
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<p><b>OBJECTIVE</b>To establish a public health risk assessment indexes for flood disaster.</p><p><b>METHODS</b>Delphi method and expert consultation were used to establish the public health risk assessment index system and scoring criteria, and the analytic hierarchy process (AHP) method was used to obtain the weight of the indexes. Then, the established index system was applied to evaluate the public health risk of the flood disaster in Anhui province, 2016.</p><p><b>RESULTS</b>A public health risk assessment system consisting of 5 categories and 17 indexes was constructed. The assessment result of the flood disaster in Anhui province of 2016 showed that the public health risk score was 0.26, suggesting that "the health emergency measures were effective, and the public health risks were effectively controlled".</p><p><b>CONCLUSIONS</b>The established indexes can effectively assess the health risk of flood disaster and also can provide the reference for other disaster assessment.</p>
Subject(s)
Disasters , Floods , Risk AssessmentABSTRACT
Objective@#To analyze the epidemiological characteristics and the pathogenic features of the influenza B virus strains circulating in Anhui province during 2017-2018 influenza surveillance year.@*Methods@#The antigenic characteristics of influenza B virus was analyzed with reference ferret anti-sera. The hemagglutinin (HA) and neuraminidase (NA) genes of influenza B viruses isolated in Anhui during this period were obtained by Sanger dideoxy sequencing. Then the phylogenetic trees and amino acid mutations were analyzed respectively.@*Results@#During 2017-2018 influenza season, the activity of B Yamagata lineage virus were stronger than B Victoria lineage virus. Most of B Yamagata lineage viruses had close antigenic relation with the vaccine strain B/Phuket/3073/2013(93.3%), but D196 N substitution was detected on HA protein in all of Yamagata lineage viruses. All of B Victoria lineage viruses had close antigenic relation with the vaccine strain B/Brisbane/60/2008(100%), meanwhile I117 V and N129D were found on HA protein. Phylogenetic analysis on B influenza viruses indicated that Yamagata clade 3 and Victoria clade 1A were predominant strains, however we found that two strains had intra-clade reassortants between HA and NA gene. The NA gene of all strains did not find a molecular mutation that was less sensitive to neuraminidase.@*Conclusions@#The WHO recommended influenza vaccine could protect from influenza B virus isolated from Anhui province. However, it is still necessary to pay close attention to its significant epitope variation in order to update the vaccine candidates in time.
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Due to adverse economic impact and social panic influences,live poultry market closure(LPM) as an effective control strategy of H7N9 influenza has become the focus of public repeatedly.So this paper reviewed transmission characteris tics of H7N9 influenza,impact of LMP on human H7N9 infection,and the effect of LMP on H7N9 influenza control.
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Objective To understand genomic characteristics of 2 strains of influenza A (H9N2) virus isolated from human infection cases in Anhui province in 2015.Methods Two human infection with H9N2 virus were confirmed by national influenza surveillance laboratory network in Anhui through viral isolation in April and September,2015,respectively.The full genomic sequences of the two viral isolates were analyzed in this study by using molecular bioinformatics software Mega 6.0.Results Human infection with H9N2 virus was first reported in Anhui province.The analysis of genomic sequence showed that the HA and NA genes of the two H9N2 isolates belonged to A/Chicken/ Shanghai/F/98(H9N2)-like lineage,and shared high identity with H9N2 virus circulating in poultry in 2013.The PB2 and MP genes belonged to the A/quail/Hong Kong/G 1/97-like lineage,and shared high homology with H7N9,H10N8 or H6N2 viruses.The amino acid sequence alignment results showed that several mutations for human infection tropism presented in the two virus strains,including Q226L,H183N and E190T in HA;S31N in M2;63-65 deletion in NA.In addition,the H9N2 influenza virus strains possessed the PSRSSR\GL motif in HA.Meanwhile several human-like signatures,including PA-100A,PA-356R and PA-409N were also found in the two virus strains.Conclusion The H9N2 viruses isolated from human infection cases in Anhui province belonged to a reassortant virus originated from different lineage H9N2 avian influenza virus.The virus has possessed several human susceptibility locus.
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Objective To understand genomic characteristics of 2 strains of influenza A (H9N2) virus isolated from human infection cases in Anhui province in 2015.Methods Two human infection with H9N2 virus were confirmed by national influenza surveillance laboratory network in Anhui through viral isolation in April and September,2015,respectively.The full genomic sequences of the two viral isolates were analyzed in this study by using molecular bioinformatics software Mega 6.0.Results Human infection with H9N2 virus was first reported in Anhui province.The analysis of genomic sequence showed that the HA and NA genes of the two H9N2 isolates belonged to A/Chicken/ Shanghai/F/98(H9N2)-like lineage,and shared high identity with H9N2 virus circulating in poultry in 2013.The PB2 and MP genes belonged to the A/quail/Hong Kong/G 1/97-like lineage,and shared high homology with H7N9,H10N8 or H6N2 viruses.The amino acid sequence alignment results showed that several mutations for human infection tropism presented in the two virus strains,including Q226L,H183N and E190T in HA;S31N in M2;63-65 deletion in NA.In addition,the H9N2 influenza virus strains possessed the PSRSSR\GL motif in HA.Meanwhile several human-like signatures,including PA-100A,PA-356R and PA-409N were also found in the two virus strains.Conclusion The H9N2 viruses isolated from human infection cases in Anhui province belonged to a reassortant virus originated from different lineage H9N2 avian influenza virus.The virus has possessed several human susceptibility locus.