Analysis of epidemic characteristics of forty-two COVID-19 cluster outbreaks in Hangzhou / 上海预防医学

Objective To determine the epidemic characteristics of forty-two coronavirus disease 2019 （COVID-19） cluster outbreaks in Hangzhou city and provide scientific evidence for further prevention and control measures. Methods Data of the COVID-19 cluster outbreaks in Hangzhou were obtained from the National Public Health Emergency Management Information System. Epidemic characteristics were summarized by reviewing the epidemiological investigation reports. Results A total of forty-two COVID-19 cluster outbreaks were documented in Hangzhou in 2020， including 130 confirmed cases and 7 cases with asymptomatic infection. The majority occurred from January to February， 2020. Moreover， 92.86% （39/42） of the cluster outbreaks were familial transmission. The proportion of the cluster outbreaks involving 2 cases accounted for 54.7% （23/42）. In the secondary cases， family members accounted for 84.15% （69/82）. Conclusion The COVID-19 cluster outbreaks in Hangzhou mainly occur in families， and the majority of the secondary cases is family members.

Analysis of epidemic characteristics of forty-two COVID-19 cluster outbreaks in Hangzhou / 上海预防医学

Objective To determine the epidemic characteristics of forty-two coronavirus disease 2019 （COVID-19） cluster outbreaks in Hangzhou city and provide scientific evidence for further prevention and control measures. Methods Data of the COVID-19 cluster outbreaks in Hangzhou were obtained from the National Public Health Emergency Management Information System. Epidemic characteristics were summarized by reviewing the epidemiological investigation reports. Results A total of forty-two COVID-19 cluster outbreaks were documented in Hangzhou in 2020， including 130 confirmed cases and 7 cases with asymptomatic infection. The majority occurred from January to February， 2020. Moreover， 92.86% （39/42） of the cluster outbreaks were familial transmission. The proportion of the cluster outbreaks involving 2 cases accounted for 54.7% （23/42）. In the secondary cases， family members accounted for 84.15% （69/82）. Conclusion The COVID-19 cluster outbreaks in Hangzhou mainly occur in families， and the majority of the secondary cases is family members.

Application of nomogram model in predicting mortality of patients infected with avian influenza A (H7 N9) / 中华临床感染病杂志

Objective To develop and validate a mortality risk prediction model for patients infected with avian influenza A H 7N9 virus.Methods A stratified and random sampling method was adopted for selection of subjects .A total of 102 patients infected with avian influenza A H7N9 virus, who were admitted to the designated hospitals in Zhejiang Province during March 2013 and March 2015, were enrolled.Standard questionnaires were used to collect data about demographic , epidemiologic and clinical characteristics , and the data were retrospectively reviewed . Univariate analysis and stepwise logistic regression analysis were used to identify the mortality risk factors of patients infected with avian influenza A H7N9 virus, and nomogram was applied to develop the risk prediction model .The accuracy of the prediction model was assessed using Concordance index (C-index) and receiver operating characteristic (ROC) curve. Results Stepwise multiple logistic regression analysis showed that age ≥60 years (χ2 =3.98, OR=2.99, 95%CI:1.05-9.21, P<0.05), increased initial neutrophil count (χ2 =6.66,OR=5.06, 95%CI:1.56-18.83, P<0.05), C-reactive protein≥120mg/L (χ2 =8.63, OR=5.15, 95%CI:1.79-16.31, P<0. 01), poor hand hygiene (χ2 =6.83, OR =10.29, 95%CI:2.18-81.49, P <0.01) and 5 days of incubation period or shorter (χ2 =7.23, OR=4.75, 95%CI:1.59-15.80, P<0.01) were independent risk factors for mortality of patients .Based on the above study , a risk prediction model of nomogram was developed.Poor hand hygiene (grade A, 100.0 points) ranked on the top of all risk factors, followed by C-reactive protein≥120 mg/L (grade B, 76.5 points), increased initial neutrophil count (grade C, 70.5 points), 5 days of incubation period or shorter (grade D, 62.0 points) and age ≥60 years (grade E, 51.0 points).The C-index and the area under the curve were 0.833 and 0.817 for the nomogram model , respectively;and the nomogram model fitted well .Conclusion Nomogram model can effectively predict and estimate the risk of death for patients infected with avian influenza A H 7N9 virus.

Analysis of epidemiologic and etiology of hepatitis E in Hangzhou, 2004-2011 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To comprehend the epidemiologic of hepatitis E and genetic characteristics of hepatitis E virus (HEV) in Hangzhou from 2004 to 2011.</p><p><b>METHODS</b>Using China information system for disease control and prevention, the incidence of hepatitis E from 2004 to 2011 in Hangzhou city, and the basic information of patients were collected. In 2011, 65 hepatitis E laboratory confirmed cases were selected by random number table sampling method from the hospitals designated infectious diseases in Hangzhou city, and acquisition of the 60 blood specimens and stool specimens of 18 copies. One city and two surrounding counties were selected by cluster random sampling method in the context of Hangzhou city, and the pig slaughters and farmers were selected as the sampling point, and acquisition of pig gallbladder specimens of 52 copies, and 30 stool samples of scatter-feed pigs, 15 stool specimens of scatter-feed rabbits. HEV was tested in samples, gene extraction and analysis of gene sequence were conducted which were compared with gene bank HEV gene sequence, and a phylogenetic tree was formed. The epidemic characteristics of hepatitis E of Hangzhou city from 2004 to 2011 were described. The difference of incidence of hepatitis E was analyzed between years and sexes in Hangzhou city.</p><p><b>RESULTS</b>There were reported a total of 3 490 cases of hepatitis E in Hangzhou from 2004 to 2011, and 3 cases of death; The average annual incidence rate was 5.79/100 000 (3 490/60 276 338). There was the overall upward trend in incidence between different years (χ² = 52.38, P < 0.01) , which the highest was 8.10/100 000 (705/8 700 373) in 2011, and the lowest incidence rate was 4.19/100 000 in 2005. The incidence of males (8.12/100 000 (2 474/30 450 990) ) was significantly higher than that of the females (3.46/100 000 (1 016/29 384 491) ) (χ² = 558.45, P < 0.05). 78 specimens of blood and stool were collected, including 16 positive samples, with positive rate 21%. There were a total of 97 specimens of pig gallbladder, pig manure and rabbit stool, including 2 positive rabbit stool samples, with positive rate of 2%. HEV genes isolated from Hangzhou were mainly type IV, with homology of 91.8% to 100%; compared with human type IV strains, the homology of nucleotide was 84.6%-96.7%; compared with type IV strain of pig genome sequence alignment, homology was 82.6%-95.2%.</p><p><b>CONCLUSION</b>Hepatitis E's incidence showed an increasing trend year by year in Hangzhou. HEV of type IV was dominant, and HEV strains in the human and swine were highly homologous.</p>

Retrospective study of risk factors of mortality in human avian influenza A(H7N9)cases in Hangzhou / 中华传染病杂志

Objective To investigate the risk factors related to mortality in human avian influenza A (H7N9)cases in Hangzhou.Methods The clinical and epidemiological data of 61 H7N9 patients whose diagnoses were confirmed by laboratory tests between 1st March,2013 and 2nd March,2014 in Hangzhou were collected.Descriptive analysis and univariate analysis were used to analyze the demographic,clinical and epidemiological characteristics and treatment outcomes.Patients were classified into improvement group and death group according to treatment outcomes,and risk factors for death were explored.Chi square test and t test were used for statistical analysis.Results A total of 61 patients were included in this study,among which 20(32.8%)patients died.The ratio of men to women for death attributed to H7N9 infection was three to one.The mean age of patients in death group was (63.6 ±3.8)years,which was older than that in improvement group ([55 .4±2.2]years,t =1 .97,P =0.05 ).The univariate analysis showed that the risk factors of mortality included over 60 years (χ2 =5 .16,P =0.02;OR =3.65 ,95 %CI :1 .19-11 .13 ),low education level (χ2 = 5 .42,P =0.02;OR =4.20,95 %CI :1 .24 - 14.00 ), chronic diseases (χ2 =4.67,P =0.03;OR=3.81 ,95 %CI :1 .12-12.69),bad hand hygiene (χ2 =4.05 , P =0.04;OR=4.67,95 %CI :1 .04 -11 .56 ),C-reactive protein (CRP)≥120 mg/L (χ2 =4.04,P =0.04;OR=6.00,95 %CI :1 .04-35 .33),increased initial neutrophil count (χ2 =3.90,P =0.05 ;OR=4.58,95 %CI :1 .01 -34.22)and decreased initial lymphocyte count (χ2 =7.12,P =0.01 ;OR =7.53, 95 %CI :1 .63 - 24.51 ).Conclusion Over 60 years,low education level,chronic diseases,bad hand hygiene,CRP≥ 120 mg/L,increased initial neutrophil count and decreased initial lymphocyte count are identified as risk factors for death in H7N9 cases in Hangzhou.