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Objective@#To find out the source and the epidemic pattern of norovirus outbreak in July, 2016 to June, 2017 in Guangzhou.@*Methods@#The stool samples and clinical information of diarrhea cases were collected by the sentinel hospitals and CDCs; a real-time RT-PCR method was used to detect the norovirus nucleic acids from the samples, the positive ones were amplified and sequenced; the partial sequences of norovirus were aligned by an online BLAST alignment, and a phylogenetic tree was constructed by a neighbor-joining method .@*Results@#A total of 854 cases with infectious diarrhea were reported by Guangzhou diarrhea surveillance network from July, 2016 to June, 2017; the gender ratio (male versus female) was 1∶0.67; 78.33% of the cases were preschool children under the age of 7 years. Totally 220 samples were detected norovirus G II+ (25.76%, including 5 double-positive samples with G I+ ). GII.Pe-GII.4.Sydney_2012 was the prevalent genotype in the second half of 2016 (94.64%), which was replaced by GII.P16-GII.2 in the first half of 2017 (67.65%). Since September 2016, the reported number of norovirus-caused diarrhea epidemic was increased gradually; the peak of epidemic curve emerged in February to March of 2017, and the number started to decrease since April. In May to June there were only 2-3 epidemics reported monthly. All the endemics from September to November 2016 were caused by genotype GII.Pe-GII.4.Sydney_2012; the endemics from December 2016 to April 2017 were mainly caused by genotype GII.P16-GII.2. Some samples from kitchen workers and babysitters were detected GII+ , which was consistent with the result of the cases′ samples.@*Conclusions@#It was the first time that the novel GII.P16-GII.2 recombinant strain outbroke occurred in Guangzhou City and homology analysis also suggested that GII.P16-GII.2 was the main source of those epidemics in 2016 -2017 winter and spring season. Furthermore, The kitchen workers and babysitters may have played an important role in the spread of norovirus.
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Objective To investigate the infection pattern and etiological characteristics of a case of human infection with highly pathogenic avian influenza A (H7N9) virus and provide evidence for the prevention and control of human infection with highly pathogenic avian influenza virus.Methods Epidemiological investigation was conducted to explore the case's exposure history,infection route and disease progression.Samples collected from the patient,environments and poultry were tested by using real time reverse transcriptase-polymerase chain reaction (RT-PCR).Virus isolation,genome sequencing and phylogenetic analysis were conducted for positive samples.Results The case had no live poultry contact history,but had a history of pulled chicken processing without taking protection measure in an unventilated kitchen before the onset.Samples collected from the patient's lower respiratory tract,the remaining frozen chicken meat and the live poultry market were all influenza A (H7N9) virus positive.The isolated viruses from these positive samples were highly homogenous.An insertion which lead to the addition of multiple basic amino acid residues (PEVPKRKRTAR/GL) was found at the HA cleavage site,suggesting that this virus might be highly pathogenic.Conclusions Live poultry processing without protection measure is an important infection mode of "poultry to human" transmission of avian influenza viruses.Due to the limitation of protection measures in live poultry markets in Guangzhou,it is necessary to promote the standardized large scale poultry farming,the complete restriction of live poultry sales and centralized poultry slaughtering as well as ice fresh sale.
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Objective To investigate the infection pattern and etiological characteristics of a case of human infection with highly pathogenic avian influenza A (H7N9) virus and provide evidence for the prevention and control of human infection with highly pathogenic avian influenza virus.Methods Epidemiological investigation was conducted to explore the case's exposure history,infection route and disease progression.Samples collected from the patient,environments and poultry were tested by using real time reverse transcriptase-polymerase chain reaction (RT-PCR).Virus isolation,genome sequencing and phylogenetic analysis were conducted for positive samples.Results The case had no live poultry contact history,but had a history of pulled chicken processing without taking protection measure in an unventilated kitchen before the onset.Samples collected from the patient's lower respiratory tract,the remaining frozen chicken meat and the live poultry market were all influenza A (H7N9) virus positive.The isolated viruses from these positive samples were highly homogenous.An insertion which lead to the addition of multiple basic amino acid residues (PEVPKRKRTAR/GL) was found at the HA cleavage site,suggesting that this virus might be highly pathogenic.Conclusions Live poultry processing without protection measure is an important infection mode of "poultry to human" transmission of avian influenza viruses.Due to the limitation of protection measures in live poultry markets in Guangzhou,it is necessary to promote the standardized large scale poultry farming,the complete restriction of live poultry sales and centralized poultry slaughtering as well as ice fresh sale.
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<p><b>OBJECTIVE</b>To evaluate the effect of supply of fresh poultry products on reducing environment contamination of avian influenza virus (AIV) in markets in Guangzhou.</p><p><b>METHODS</b>A total of 40 markets, including 20 selling alive poultry and 20 selling fresh poultry products, were selected randomly in Guangzhou to conduct environment surveillance in 80 poultry stalls every 4 months from July 2014 to April 2015. Four smear samples were collected from different sites of each poultry stall to detect nucleic acid of AIV. The positive samples were further detected for AIV subtype H5, H7 and H9 nucleic acids.</p><p><b>RESULTS</b>Among 40 alive poultry stalls, 95.0% (38/40) kept alive poultry overnight, 25.0% (10/40) were disinfected daily, 95.0% (38/40) were cleaned up weekly, 95.0% (38/40) were closed for one day every month. Among 40 fresh poultry product stalls, 20.0% (8/40) were disinfected daily, 90.0% (36/40) were cleaned up weekly, and 96.0% (38/40) ever sold dressed poultry from alive poultry markets. The positive rate of AIV in alive poultry markets was 40.4% (252/623), higher than that in fresh poultry product markets (32.3%, 197/610), the difference was significant (χ(2)=8.85, P=0.003), and the positive rate of subtype H9 virus in alive poultry markets was 28.6% (178/623), higher than that in fresh poultry product markets (16.2%, 99/610), the difference was significant (χ(2)=26.95, P<0.001). In fresh poultry product markets, the positive rate of AIV in stalls selling dressed poultry was 37.3% (180/482), higher than that in stalls selling no dressed poultry (13.3%, 17/128), the difference was significant (χ(2)=26.78, P<0.001), and the positive rate of subtype H9 virus in stalls selling dressed poultry was 19.1% (92/482), higher than that in stalls selling no dressed poultry (5.5%, 7/128), the difference was significant (χ(2)=13.80, P<0.001). Both the positive rate of AIV and the positive rate of subtype H9 virus were highest in the second round surveillance (October 2014). The differences in AIV and its subtype H5, H7 and H9 virus positive rates of environmental samples from four different sites were not significant, respectively. In the same sample site, the positive rate of subtype H9 virus in alive poultry markets was higher than that in fresh poultry product markets the difference was significant (P<0.05).</p><p><b>CONCLUSIONS</b>The supply of fresh poultry products could effectively reduce the level of environment contamination of AIV in markets. Dressed poultry supplement caused the risk of AIV spread in fresh poultry product markets.</p>
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Animals , China , Commerce , Disinfection , Environmental Microbiology , Influenza A virus , Poultry , Poultry ProductsABSTRACT
<p><b>OBJECTIVES</b>To investigate a survey about acceptance of central slaughtering of live poultry in residents of Guangzhou.</p><p><b>METHODS</b>We conducted a telephone survey by sampling residents with fixed-line telephone and with normal hearing, whose age is more than 15 years, by Mitofsky-Waksberg two-stage method during Jan 6(th) to 8(th), 2014. 358 residents finished the telephone questionnaire by 12 320 health hot line. We investigated the acceptance rate of city-wide central slaughtering permanently. We compared the difference between the respondents and the 2010 Guangzhou census data by Cohen's effect sizes (w) and weighted by population age and sex. We used χ(2) test to compare the acceptance rate of central slaughtering in residents with different characteristic. We used multiple logistic regression analysis to analyze the factors.</p><p><b>RESULTS</b>The difference in gender and age was small between respondents and the 2010 Guangzhou census data (w value was 0.13, 0.28, respectively), but that in education and marital status was large (w value was 0.52, 0.31, respectively). 49.0% (95% CI: 43.7%-54.3%) accept city-wide central slaughtering permanently. The acceptance rate of city-wide central slaughtering permanently in those who bought fresh, chilled and frozen poultry in their family in previous year was 54.3% (133/245), 60.0% (57/95) and 59.8% (49/82), respectively. It was more than those who didn't buy fresh, chilled and frozen poultry (38.1% (43/113), 44.9% (118/263) and 45.7% (126/276); χ(2) values were 8.15, 6.40 and 5.03; P values were 0.004, 0.011 and 0.025, respectively). The acceptance rate of city-wide central slaughtering permanently in those who deem fresh poultry taste better than live poultry was 64.9% (24/38). It more than those who deem not (47.0%, 151/320) (χ(2) = 4.22, 6.02, P = 0.040, 0.014, respectively). The acceptance rate of city-wide central slaughtering permanently in the male (OR = 2.68, 95% CI: 1.64-4.37) and those who deem getting sick due to buying live birds from LPM (OR = 1.72, 95% CI: 1.05-2.82), who can accept only fresh poultry carcass supply (OR = 2.39, 95% CI: 1.33-4.30), Who bought live poultry in their family in previous year (OR = 0.29, 95% CI: 0.11-0.74), who will decrease the consumption after ban on live poultry sale (OR = 0.50, 95% CI: 0.30-0.83) was 58.6% (109/186), 59.0% (92/156), 60.7% (139/230), 44.9% (132/295), 36.6% (68/186), respectively.</p><p><b>CONCLUSION</b>In the early stage of avian influenza A(H7N9) epidemic in Guangzhou, the rate of acceptance of central slaughtering permanently in residents was not so high. Who deem getting sick due to buying live birds from LPM, who could accept only fresh poultry carcass supply and the male more accept city-wide central slaughtering permanently.</p>