H9N2 avian influenza virus poses a persistent public health concern due to its zoonotic potential. This study investigated the epidemiological and clinical characteristics of human H9N2 avian influenza infection in Changsha City, along with related environmental surveillance data, to provide a scientific basis for disease prevention and control. From January 2015 to December 2025, a total of 11 human H9N2 avian influenza cases were collected from historical surveillance data of the Changsha CDC in Changsha City. Cases occurred sporadically throughout the year; most (90.91%, 10/11) were mild, one severe case was co-infected with two types of respiratory pathogens, and the majority (72.73%, 8/11) were children under 5 years old. Among the 10 cases with available exposure history, 70.00% had been exposed to live poultry or LPMs, with the H9 and N2 subtypes detected in related environmental samples at rates of about 76%. Genetic analysis showed that the H9N2 viruses from human cases were highly homologous to H9N2 viruses found in the live poultry environment in Changsha City, while also exhibiting diverse mutations in key functional sites and domains. Environmental samples from large live poultry markets exhibited a significant year-on-year increase in positive rate (χ 2 =111.30, P <0.001), resulting in a substantially higher average rate in 2020-2024 versus 2014-2019 (77.11% vs. 47.43%; χ 2 =158.24, P <0.001). In conclusion, sporadic human H9N2 infections, predominantly affecting children, were mostly associated with live poultry exposure, with no evidence of human-to-human spread, while environmental data revealed a sharply increasing contamination trend in markets, pointing to a heightened risk.

Objective:To understand the epidemiological and clinical characteristics of human infection with avian influenza A(H3N8) virus and the molecular biological characteristics of the pathogen, and provide scientific evidence for the prevention and control of human infection with avian influenza A(H3N8) virus.Methods:An epidemiological investigation was conducted for a case of human infection with avian influenza A(H3N8) virus in Changsha in May 2022 to collect the information about exposure history, route of infection, onset and treatment, potential contacts and other possible exposures for a descriptive analysis. Nucleic acid detection and gene sequencing were used to detect the pathogen and analyze the genetic characteristics.Results:The case had a history of exposure to live poultry trading market 6 days before the onset of illness. Subtypes H3 and N8 of avian influenza virus were detected in live poultry markets. Deep gene sequencing showed that the virus had adaptive mutations in mammals, reduced sensitivity to alkamine agent, and no resistance mutations related to neuraminidase inhibitors and polymerase inhibitors were detected.Conclusion:The case was infected due to exposure to the live poultry market environment contaminated by avian influenza A(H3N8) virus, and no human to human transmission was found.

Objective To understand the distribution and contamination of avian influenza virus in the external environment of live poultry markets and analyze the serological test results of population with occupational exposure in Changsha, Hunan province, from 2018 to 2021, and provide evidence for the prevention and control of human infection with avian influenza virus and policy-making. Methods From January 1, 2018 to December 31, 2021 in Changsha, the external environmental samples of live poultry markets were collected and detected for avian influenza virus nucleic acid by real-time reverse transcription polymerase chain reaction, and horse blood cell hemagglutination inhibition test（HI） was used to detect H5N6and H7N9 antibodies in serum samples, and turkey blood cell was used to detect H9N2 antibodies in serum samples. Software SPSS 19.0 was used to analyze the data and compare the positive rates of different samples, at different areas and at different times. Results From January 1, 2018 to December 31, 2021, a total of 813 external environmental samples of live poultry markets and 150 serum samples of people with occupational exposure to poultry were collected in Changsha. The average positive rate of avian influenza virus in the external environment of live poultry markets was 64.58% in Changsha from 2018 to2021, the annual positive rate showed an increasing trend from 2019 to 2021, and 254 samples were positive for subtype H9,accounting for the highest proportion. Among the six different types of sample, the positive rate in cage surface swabs was highest（79.03%）, and the positive rate in poultry throat swabs was lowest（10.00%）. Among the districts and counties in Changsha, Yuelu had the highest positive rate of avian influenza virus（94.67%）. In terms of time distribution, the average annual positive rate was highest in the fourth quarter（67.50%）, and lowest in the third quarter（57.82%）, the positive rate was lower in summer than in winter. From 2018 to 2021, one H9N2 antibody positive sample was detected in the serological test for the population with occupational exposure to poultry.There were significant differences in the positive rate of avian influenza virus among different types of samples and different areas （P＜0.05）.Conclusion The main subtype of avian influenza virus was H9 in the external environment of live poultry market in Changsha during 2018-2021.Winter was the season with high detection rate,and there was H9N2 recessive infection in population with occupational exposure.Trading,transportation and personnel flow in live poultry markets were high-risk factors for the cross-species spread of avian influenza virus.Live poultry markets should be regarded as a key places for avian influenza prevention and control,and continuous surveillance for avian influenza virus should be carried out to prevent the spread of avian influenza virus in human.

目的 分析长沙市2014-2018年9个区县(市)其它感染性腹泻病的流行病学特征,为制定长沙市其它感染性腹泻病的防控提供依据.方法 从中国疾病预防控制信息系统获取2014-2018年长沙市其它感染性腹泻病分地区、年龄和职业的发病数,描述该市其它感染性腹泻病流行病学特征.结果 长沙市其它感染性腹泻病发病数呈逐年上升趋势,12月～次年2月出现发病高峰,7～8月出现次高峰;发病年龄集中在0～3岁组,以散居儿童为主;发病总数居前3位地区分别为浏阳市、长沙县和雨花区,年均发病率居前3位地区分别为雨花区、浏阳市和长沙县.聚集性疫情均由诺如病毒感染引起,疫情数呈逐年上升趋势.结论 长沙市其它感染性腹泻病病例数和疫情均有逐年上升的趋势,防控重点人群为0～3岁散居儿童.应有针对性地提早做好其它感染性腹泻病防控.

In this study, we report three cases of sporadic Creutzfeldt–Jakob disease in China, two confirmed cases and one probable case. The aim of this study was to enrich the data regarding clinical and epidemiological features of this disease and to provide reference for the diagnosis, control, and prevention of sporadic Creutzfeldt–Jakob disease.

Objective: Hand, foot, and mouth disease (HFMD) is a serious public health issue in many countries; however, its transmissibility in county-level outbreaks remains unclear. The aim of this study is to estimate the transmissibility of HFMD epidemics on both city level and county level, for a better understanding of the transmission dynamics of HFMD epidemics. Study design: Simulation based on data obtained from the China Information System for Disease Control and Prevention. Methods: The weekly number of reported HFMD cases from April 2009 to December 2017 in nine regions of Changsha City was collected. A susceptible-infectious-recovered model was used to estimate the transmissibility of HFMD. The reproduction number of reported cases during the ascending (denoted as R-ase) and descending (denoted as R-des) period was used to describe the transmissibility of HFMD. Results: The R-asc and R-des for HFMD in Changsha was 1.44 (95% confidence interval [CI]: 1.41 -1.48) and 0.71 (95% CI: 0.69-0.73), respectively. There was no statistical significance of R-asc values among nine regions (F = 1.056, P = 0.396), nor of R-des values among nine regions (F = 1.676, P = 0.106). The average R-asc (1.53, 95% CI: 1.46-1.61) from 2009 to 2012 was higher than the one (1.37, 95% CI: 1.34-1.40) from 2013 to 2017 (t = 3.974, P < 0.001), but the average R-des (0.67, 95% CI: 0.63-0.70) from 2009 to 2012 was lower than the one (0.74, 95% CI: 0.73 -0.76) from 2013 to 2017 (t = -3.751, P < 0.001). Conclusions: The epidemic of HFMD in Changsha City is still grim, and integrated strategies should be taken for controlling and preventing HFMD. (C) 2019 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

BACKGROUND: Detecting avian influenza virus has become an important public health strategy for controlling the emerging infectious disease. METHODS: The HIS (hospital information system) modified influenza surveillance system (ISS) and a newly built pneumonia surveillance system (PSS) were used to monitor the influenza viruses in Changsha City, China. The ISS was used to monitor outpatients in two sentinel hospitals and to detect mild influenza and avian influenza cases, and PSS was used to monitor inpatients in 49 hospitals and to detect severe and death influenza cases. RESULTS: From 2005 to 2016, there were 3,551,917 outpatients monitored by the ISS system, among whom 126,076 were influenza-like illness (ILI) cases, with the ILI proportion (ILI%) of 3.55%. After the HIS was used, the reported incident cases of ILI and ILI% were increased significantly. From March, 2009 to September, 2016, there were 5,491,560 inpatient cases monitored by the PSS system, among which 362,743 were pneumonia cases, with a proportion of 6.61%. Among pneumonia cases, about 10.55% (38,260/362,743) of cases were severe or death cases. The pneumonia incidence increased each year in the city. Among 15 avian influenza cases reported from January, 2005 to September, 2016, there were 26.7% (4/15) mild cases detected by the HIS-modified ISS system, while 60.0% (9/15) were severe or death cases detected by the PSS system. Two H5N1 severe cases were missed by the ISS system in January, 2009 when the PSS system was not available. CONCLUSIONS: The HIS was able to improve the efficiency of the ISS for monitoring ILI and emerging avian influenza virus. However, the efficiency of the system needs to be verified in a wider area for a longer time span in China.

Seven cases of avian influenza A H7N9 virus infection were reported from February to April 2017 in Changsha City. Viral genome was acquired by RT-PCR, aligned with other H7N9 viruses using Clustal W, and phylogenetic trees were constructed using the neighbor-joining method. Our results showed the representativeness of H7N9 virus infections in Middle Yangtze River City. The hemagglutinin segment contained Thr160Ala, Gly186Val and Gln226Leu substitutions, which are associated with increased binding affinity in humans. Phylogenetic analysis indicated that H7N9 viruses had an avian origin, and belonged to the Yangtze River Delta lineage. The proportion of PB2 Ala588Val substitutions in viruses revealed a significantly increasing in recent years, from 0.8 % (1 of 128 cases) to 84.9 % (275 of 324 cases). The data indicate that H7N9 viruses may be more capable of infecting mammals, even though they are still considered low pathogenic avian influenza virus. Hence, the prevalence and genetic evolution of this virus should be closely monitored to prevent more severe human pandemics.

Objectives: By adopting a new method, this study aimed to analyse the epidemiological characteristics of hand, foot, and mouth disease (HFMD) in nine districts and counties (cities) of Changsha City, China, from 2009 to 2017. Methods: The reported HFMD cases were collected in Changsha from 2009 to 2017. The traditional descriptive method and a new method (index system) including six indices (richness index N, Simpson diversity index D, Shannon diversity index H, Berger-Parker dominance index d, Shannon evenness index E, and Morisita?Horn similarity index C) were used to describe the epidemiological characteristics of HFMD in Changsha. Results: There were 214155 HFMD reported in Changsha during the study period. The incidence of the disease was higher in even-numbered years (2010, 2012, 2014, and 2016) than in uneven-numbered years (2009, 2011, 2013, 2015, and 2017), with two peaks in May to June and October to November every year. The age of onset was mainly from 0 to 5?years old, and the death was mainly from 0 to 2?years old. According to occupational classification, districts and counties (cities) had a high degree of similarity of the composition of HFMD, and there was no regional difference. Conclusions: Changsha had a yearly increasing trend of HFMD from 2009 to 2017, and the key population for prevention and control was children aged in 0?5?years old. Seasonal distribution of high incidence and peak incidence were occurred in even-numbered years. The sub-regions of the city shared moderate diversity and high similarity of occupational distribution of HFMD.

Objective To quantitatively evaluate the impact of heat wave on the prevalence of three kinds of common infectious diseases. Methods An interrupted time series (ITS) technique was used to detect the trend changes in the daily-reported case number of three kinds of infectious diseases (including bacillary dysentery, hand-foot-mouth disease (HFMD) and mumps) during the period of heat wave from June 30th to August 16th in 2013 in Changsha City, Hunan Province. Results The dailyreported case number of bacillary dysentery declined after the occurence of heat wave (b2 =-0.20, P =0.30), but it showed a significantly increasing trend over time (b3 =0.10, P =0.56). The daily-reported case number of HFMD increased after the occurence of heat wave (b2 =0.04, P=0.63), but it showed a significantly decreasing trend over time (b3 =-0.18, P=0.76). The daily-reported case number of mumps decreased after the occurence of heat wave (b2 =-0.34, P =0.06), but it reversed from a decreasing trend to an increasing trend over time (b3 =3.82, P=0.00). Durbin-Watson test indicated the possibility of auto-correlation (DW: 1.43-1.81). Conclusions In terms of possible impact of auto-correlation, it can not be ascribed changes in the daily-reported case number of three kinds of infectious diseases and their trends over time to heat wave.

[Objective] To understand the epidemic situation of influenza and distribution of dominant virus types in Changsha City,find out the epidemic law of influenza,and provide scientific evidence for influenza prevention and control.[Methods] The data of influenza like illness (ILI) and pathogenic monitoring from January,2012 to December,2016 were collected.The descriptive analysis was used in results of epidemiological and etiological monitoring.[Results] The difference in the percentage of influenza like illness in the outpatients (ILI％) was statistically significant among different years (x2=5 692.835,P＜0.01).There were two peaks of ILI％ in Changsha City in a year,the first peak appeared during the 2nd and 8th week (January to February) and second appeared during the 22nd and 30th week (July to August).The difference in ILI distribution was statistically significant among age groups (x2=1 569.46,P＜0.01).From 2012-2016,there was statistically significant difference in the positive rate of influenza virus among different years (x2=107.55,P＜0.01).[Conclusion] The influenza epidemic in Changsha City is characterized by two peaks in winter to spring and in summer,and the types of virus type change frequently.It is necessary to carry out the influenza surveillance to provide further guidance for the prevention and control of the disease.

Objective To use a mathematical model to simulate an influenza outbreak in a school in order to assess the effectiveness of isolation (Iso), antiviral therapeutics, antiviral prophylactics (P), vaccination prior to the outbreak, and school closure (for 1 [S1w], 2 or 3 weeks). Methods This study developed a susceptible–exposed–infectious/asymptomatic–recovered model to estimate the effectiveness of commonly used interventions for seasonal influenza outbreaks in school. Results The most effective single-intervention strategy was isolation with a total attack rate of 1.99% and an outbreak duration of 30 days. The additional effectiveness of antiviral therapeutics and prophylactics and vaccination (prior to the outbreak) strategies were not obvious. Although Iso+P, P+Iso+S1w, four-, and five-combined intervention strategies had commendable effectiveness, total attack rate decreased only slightly, and outbreak duration was shortened by 9 days maximum, compared with the single-intervention isolation strategy. School closure for 1, 2 or 3 weeks was futile or even counterproductive. Conclusion Isolation, as a single intervention, was the most effective in terms of reducing the total attack rate and the duration of the outbreak.

Three cases of the avian influenza A (H9N2) virus have been documented in Changsha, which is a large city that has nine districts and a population of 7.04 million in central South China. Among these patients, one was a girl and two were boys. The ages of the patients were 9 months, 2 years, and 15 years. Two cases of H9N2 were detected in September, 2015 and one was detected in 2017. Two patients were children who had not reached the age for kindergarten and one was a student. These three cases were all mild and were detected in a sentinel hospital of the Chinese Influenza Surveillance System. We describe the clinical and epidemiological features of the youngest patient with H9N2 in 2017 and the surveillance results of the H9N2 virus in live poultry markets in Changsha. From January 2014 to December 2017, 4212 samples were collected in live poultry markets in Changsha, among which 25.81% (1087/4212) were H9N2-positive. Public health concerns should be addressed for emerging H9N2 virus infection, and more strategies should be performed before this virus mutates to be more transmissible and highly pathogenic.

目的 探讨活禽“养殖-交易-消费”的网络式消费模式,了解长沙市禽类养殖和交易场所H5N1亚型流感病毒传播的流行病学特征.方法 本研究采用现场调查的方式,调查长沙市活禽养殖交易网络,养殖场、批发市场、零售市场活禽中禽流感病毒的感染情况.采用基因测序方法,开展病毒基因特征分析.结果 长沙市平均每日生产活禽9万余只,批发市场每日进货和销售量为13万余只,零售市场每日进货和销售量为15万余只.活禽监测结果显示,养殖场未检出H5N1阳性,批发市场和零售市场病毒分离阳性率分别为7.57％和13.30％.环境监测结果显示,养殖场、批发市场和零售市场病毒核酸阳性率分别为8.73％、23.37％、34.32％,经logistic回归分析,批发市场传播禽流感的风险高于养殖场所、零售市场传播禽流感的风险高于批发市场,OR值为2.010 (95％CI:1.602～2.522).基因测序结果显示,活禽交易场所检出的病毒为高致病性禽流感H5N1病毒.结论 长沙市活禽养殖和交易网络庞大而复杂,非常有利于禽流感病毒的传播,而且传播速度非常快,溯源难度大.长沙市活禽H5N1感染率高,需要建立长效的多部门联防联控机制.

We report rabies virus transmission among solid organ transplantation recipients in Changsha, China, in 2016. Two recipients were confirmed to have rabies and died. Our findings suggest that more attention should be paid to the possibility of rabies virus transmission through organ transplantation for clinical and public health reasons.

Objective To predict the incident number of mumps in Changsha using seasonal autoregressive integrated moving average(SARIMA)model. Methods We collected the data of incident number of mumps reported in Changsha from 2005 to 2015,then,with the data between 2005 and 2014 as the modeling data,and that in 2015 as the validation data,we built and validated a SARIMA model and used it to predict the incident number of mumps in Changsha in 2016. Results SARIMA(3,0,0) × (1,0,0)12 model could well fit the actual data,the expansion of the model was:Yt = 222. 545 +1. 225Yt - 1 - 0. 713Yt - 2 + 0. 291Yt - 3 + 0. 366Yt - 12 - 0. 448Yt - 13 + 0. 261Yt - 14 - 0. 107Yt - 15 + at . The validation data and model prediction data were analyzed,and the results demonstrated that there was significant correlation between them(r = 0. 61,P <0. 001). SARIMA model predicted that the incident number of mumps occurred in Changsha in the whole year of 2016 would reach 3 032,the average monthly incident number was 253. Conclusion SARIMA model can be used to predict the incident number of mumps. It predicted that the mumps outbreak might still show a trend of high incidence in Changsha in 2016.

Objective To calculate the proportion of asymptomatic (p) and transmissibility (basic reproduction number,R0) in influenza outbreaks,and assess the effectiveness of control countermeasures for the influenza outbreaks under these conditions.Methods The data of all influenza outbreaks occurred from January 1,2004 to December 31,2013 were collected for estimating the p and R0,and the data of outbreaks reported from January 1,2011 to December 31,2013 were used to calculate the period of infection of influenza.A susceptible-exposed-infectious/asymptomatic-removed (SEIAR) model was built based on the natural history of influenza.Thus the p and R0 were calculated by curve fitting,and the effectiveness of case isolation,antivirals for treatment and prophylaxis use,school closure for one week,and the vaccination prior to or during the outbreak were estimated by the modeling.Results The mean value of infection period was (4.27± 1.98),and the mean value ofp of seasonal influenza was (0.190 3±0.295 3).The mean value of R0 was (10.12±5.16),and among which the mean value of R0 of influenza H1N 1 was (11.32±5.74) and the mean value of R0 of seasonal influenza was (7.79±2.67).There was a significant difference of R0 between the two subtypes of influenza (P=0.006).Under the condition of different values ofp and R0,there was a large heterogeneity of the effectiveness of isolation;the effect of vaccination prior to the outbreak and antivirals for prophylaxis use were not impacted by the two parameters;but differently,the effect of vaccination during the outbreak and antiviral for treatment use were negative related to the two parameters;the effect of school closure for one week was not obvious no matter if the values ofp and R0.Conclusions The p and R0 of influenza H1N1 are higher than those of seasonal influenza.It is needed to control the influenza outbreak based on the values ofp and R0.

Objective To conduct early warning of infectious diarrhea by using logistic differential equation model.Methods Reported infectious diarrhea cases from 2010 to 2015 in Changsha City were collected to build a dataset for the modeling.Curve fitting of the logistic model and the dataset was conducted by software Berkeley Madonna 8.3.18.R2 was employed to evaluate the effectiveness of the curve fitting.The difference was statistically significant(P ＜ 0.05).The months of early warning in each year were calculated by the parameters of the model accordingly.Results The epidemic cycle of infectious diarrhea was relatively sta ble and obvious in Changsha City.R2 of model fitting in each year was larger than 0.9,with the difference was statistically significant(P ＜0.05).The incidence of infectious diarrhea speeded up in June from the year from 2010 to 2013,but it was in July in 2014 and in May in 2015.The early warning months were May,June and April correspondingly.Conclusion Logistic model could be used for the early warning of infectious diarrhea.The early warning month could be May in Changsha City.

[Objective] To forecast the incidence rate of AIDS in Changsha with ARIMA model and GM (1,1) model and compare their effects.[Methods] The incidence data of AIDS in Changsha from 2006-2016 were collected to establish ARIMA model and GM (1,1) model,and the two models were fitted and applied to forecast the incidence rate of AIDS in 2017 and 2018,and the effects of fitting and prediction of two models were compared.[Results] The incidence rates of AIDS in Changsha in 2017 and 2018 forecasted by ARIMA (1,1,1) model were 6.19/100 000 and 8.19/100 000,and forecasted by GM (1,1) model were 6.19/100 000 and 8.19/100 000.[Conclusion] The fitting results of ARIMA and GM (1,1) are similar with the incidence trend of AIDS in Changsha,but the forecast effect of ARIMA model on the incidence rates of HIV/AIDS in Changsha from 2006-2016 is better than that of GM (1,1) model,the prediction accuracy P is higher than that of GM (1,1) model,and the mean absolute error (MAE) is less than that of GM (1,1) model.

Objective To explore the relationship between hepatitis E and meteorological factors.Methods The monthly reported cases of hepatitis E and meteorological data in Changsha from 2004 to 2015 were collected.Through the comparison of discrete test and model fitting effect indicators,advantages and disadvantages of Poisson regression model and negative binomial regression model were evaluated.The optimal model was selected to analyze the meteorological factors of the incidence of hepatitis E.Results From 2004 to 2015,there were 1 355 cases reported with hepatitis E in Changsha.The annual incidence was (0.21-2.77) per 100 000 people.There were sporadic cases in each month,but most occurred between February and May.According to the results of correlation analysis of meteorological data,monthly total precipitation,monthly average air pressure,monthly average wind speed,monthly average temperature,monthly average relative humidity,monthly days of raining and monthly sunshine hours were enrolled into the model.The indicators of discrete test and model fitting effect showed that the effect of negative binomial regression model was better than that of Poisson regression model.Negative binomial regression model analysis showed that monthly average temperature 〔b=-0.024,95%CI (-0.036,-0.013)〕,monthly days of raining 〔b=0.047,95%CI(0.032,0.062)〕,monthly sunshine hours 〔b =0.003,95%CI (0.001,0.005)〕 were influence factors of hepatitis E in Changsha (P<0.05).Conclusion Lowered average temperature,more rainy days and longer sunshine hours are the meteorological factors of increased number of cases with hepatitis E.