Objective: To investigate the spatio-temporal clustering characteristics of influenza in Shaoxing City, Zhejiang Province from 2015 to 2024, so as to provide the basis for formulating influenza prevention and control strategies. Methods: Influenza case data in Shaoxing City from 2015 to 2024 were collected through the Infectious Disease Surveillance Reporting System of the Chinese Disease Prevention and Control Information System. Descriptive epidemiological methods analyses were used to analyze the epidemiological characteristics of influenza. Spatial autocorrelation and spatio-temporal scanning were used to analyze the spatio-temporal clustering characteristics of influenza. Results: A total of 328 759 influenza cases were reported in Shaoxing City from 2015 to 2024, with an average annual reported incidence of 639.90/100 000, which showed an upward trend (AAPC=68.95%, P<0.05). The peak incidence period was from December to February of the following year, with 193 051 cases reported, accounting for 58.72%. There were 165 408 male cases and 163 351 female cases, with a male-to-female ratio of 1.01∶1. Children and adolescents aged 0-<15 years constituted the high-incidence population, while students represented the predominant occupational category, comprising 113 589 cases (34.55%). Keqiao District, Shengzhou City, and Yuecheng District had the top three average annual reported incidence of influenza, at 995.64/100 000, 734.66/100 000, and 687.44/100 000, respectively. Spatial autocorrelation analysis showed that, there were 155 high-high aggregation areas in Shaoxing City from 2015 to 2024, which gradually expanded from the local aggregation in the central part of Shengzhou City to Keqiao District and then spread to Yuecheng District. Spatio-temporal scanning analysis showed that, from November 2023 to February 2024, the strongest spatio-temporal clustering of influenza centered on Keqiao Street in Keqiao District, covering 11 towns (streets) in Yuecheng District and Keqiao District. From 2015 to 2018, the primary-type clustering of influenza was mainly concentrated in Xinchang County and Shengzhou City. After 2019, they gradually shifted to Yuecheng District and Keqiao District, with the main clustering period being from November to February of the following year. Conclusions The incidence of influenza in Shaoxing City from 2015 to 2024 showed an upward trend, with obvious spatio-temporal clustering. The clustering area expanded from Shengzhou City in the central region to Keqiao District and Yuecheng District in the northern region, mainly clustering from November to February of the following year.

Objective: To analyze epidemiological characteristics of brucellosis in Shaoxing City, Zhejiang Province from 2005 to 2023, so as to provide the basis for developing targeted control measures. Methods: Data of brucellosis cases and epidemiological investigation in Shaoxing City from 2005 to 2023 were collected from the Monitoring and Reporting Management System of the Chinese Disease Prevention and Control Information System. The epidemiological characteristics of brucellosis were descriptively analyzed, the trend in incidence of brucellosis was analyzed using average annual percent change (AAPC). Results: A total of 270 cases of brucellosis were reported in Shaoxing City from 2005 to 2023, with an average annual incidence of 0.29/105. The AAPC was 0.812%, with no significant changing trend (P>0.05). The incidence of brucellosis peaked from February to March, with 80 cases (29.63%). The reported cases were mainly distributed in Shangyu District (139 cases, 51.48%) and Shengzhou City (74 cases, 27.41%). There were 188 male cases and 82 female cases, with a male-to-female ratio of 2.29∶1. The cases were primarily concentrated in the age group of 40 to <70 years, with 205 cases accounting for 75.93%. Among these, 86 cases were reported in the 50 to <60 years of age group, accounting for 41.95%. The majority of the cases were farmers, with 187 cases accounting for 69.26%. The median interval from onset to diagnosis was 22.73 (interquartile range, 39.97) days, with a delayed diagnosis rate of 62.96%. Infections through breeding, selling and transporting cattle and sheep resulted in 164 cases (60.74%), and through buying and slaughtering resulted in 36 cases (13.33%). An outbreak of brucellosis was reported in Xinchang County in 2018, with three confirmed cases. Conclusions The incidence of brucellosis in Shaoxing City had no significant change from 2005 to 2023. The peak period was from February to March. The cases were mainly distributed in Shangyu District and Shengzhou City. People aged 50 to <60 years, males, and farmers were the key groups for prevention and control.

Objective: To investigate the epidemiological characteristics of hemorrhagic fever with renal syndrome (HFRS) in Shaoxing City from 2006 to 2022, so as provide insights into improvements of the HFRS control strategy. Methods: Data pertaining to HFRS cases in Shaoxing City from 2006 to 2022 were captured from the Surveillance System of China Information System for Disease Control and Prevention. The temporal, population and regional distributions of HFRS were analyzed using the descriptive epidemiological method, and the trends in incidence of HFRS were evaluated using annual percent change (APC). Results: Totally 1 022 HFRS cases were reported in Shaoxing City from 2006 to 2022, with annual average incidence of 1.22/105 and three deaths. The incidence of HFRS appeared a tendency towards a decline in Shaoxing City from 2006 to 2022 (APC=-11.101%, t=-9.930, P<0.001), and the incidence of HFRS peaked from May to June and from November to January of the next year. A higher incidence of HFRS was seen in men than in women (1.76/105 vs. 0.68/105; χ2=201.361, P<0.001). There were 714 HFRS cases at ages of 30 to 59 years (69.86%), and farmers were the predominant occupation (78.18%). The three counties with the largest number of HFRS cases included Zhuji (366 cases), Xinchang (263 cases) and Shengzhou (134 cases). The incidence of HFRS was lower in urban districts (Yuecheng, Keqiao and Shangyu) than in counties (Zhuji, Shengzhou and Xinchang) (0.58/105 vs. 1.96/105; χ2=326.880, P<0.001). Conclusion The incidence of HFRS appeared a tendency towards a decline in Shaoxing City from 2006 to 2022, and the incidence was high in late spring, early summer and winter. The HFRS cases were mainly males, young and middle-aged people, and farmers, and predominantly distributed in counties. Targeted control measures are needed.

Objective: To understand the epidemiological characteristics of viral hepatitis B in Shaoxing from 2008 to 2018,so as to provide basis for formulating the viral hepatitis B prevention and control strategy. Methods: The data of viral hepatitis B cases in Shaoxing from 2008 to 2018 were collected from infectious diseases reporting and management system. Descriptive epidemiological method was employed to analyze the time,place and population characteristics of viral hepatitis B cases in Shaoxing. Annual percentage change（APC）was calculated to analyze the development trend of viral hepatitis B. Results : From 2008 to 2018,a total of 22 764 cases of viral hepatitis B were reported in Shaoxing,with an average annual incidence rate of 42.24/100 000 and a standardized incidence rate of 39.19/100 000. The incidence rate of viral hepatitis B decreased from 2008 to 2018,among which the APC from 2012 to 2018 was -18.00% with a significantly downward trend（P<0.05）. Six counties,cities or districts in Shaoxing reported cases of viral hepatitis B,of which Zhuji（49.40/100 000）,Yuecheng（44.17/100 000）and Xinchang（43.28/100 000）ranked top three in average annual incidence rate. The incidence rate of viral hepatitis B in men was 57.07/100 000,which was higher than 27.33/100 000 in women（P<0.05）.The age of onset was mainly 25-59 years old,with 16 941 cases（74.42%）reported. The top three occupations were farmers,workers and migrant workers,with 15 013（65.95%）,2 730（11.99%）and 1 121（4.92%）cases reported,respectively. Conclusions The incidence of viral hepatitis B in Shaoxing from 2008 to 2018 showed a downward trend. Farmers,workers and migrant workers aged 25-59 years were at high risk of hepatitis B infection.