Objective: To estimate the epidemic threshold and graded intensity thresholds of influenza in Zhejiang Province from 2012 to 2023 using the moving epidemic method (MEM), and evaluate the intensity of influenza epidemics, so as to provide the reference for influenza prevention and control in Zhejiang Province. Methods: The positive rates of influenza virus per week during the influenza epidemic seasons (from 40th week to 20th week of the following year) in Zhejiang Province from 2012 to 2022 were collected through the Chinese Influenza Surveillance Information System. A MEM model was established and optimized using cross-validation. The maximum accumulated rates percentage was used to divide the epidemic into pre-epidemic, epidemic, and post-epidemic periods, and to estimate the epidemic thresholds and graded intensity thresholds. The intensity of influenza epidemics in Zhejiang Province during the 2022-2023 epidemic season were assessed. Results: The positive rates of influenza virus in five epidemic seasons from 2012 to 2022 were included in the model. The MEM model performed best when the parameter δ was set to 1.5, with a sensitivity of 0.971, a specificity of 0.745, and a Youden's index of 0.716. According to the model analysis, the epidemic beginning and ending thresholds of influenza in Zhejiang Province during the 2022-2023 epidemic season were 19.32% and 10.92%, respectively, and the medium, high, and extremely high intensity thresholds were 48.65%, 63.49%, and 68.47%, respectively. During 2022-2023, the influenza epidemic was in the pre-epidemic period from the 40th week in 2022 to the 7th week in 2023; the epidemic period was from the 8th to the 18th week, the epidemic intensity was low in the 8th week and increased to a high level in the 9th week, and reached to a extremely high level from the 10th to the 13th week, then fell to the high and the medium level in the 14th week and 15th week, respectively, and fell to a low level from the 16th to the 18th week; the influenza epidemic entered the post-epidemic period since the 19th week. Conclusion MEM could be applied for evaluation of influenza epidemic intensity, providing the reference for early identification and taking graded preventive and control measures.

Objective:To evaluate the impact of colonoscopy on the incidence of colorectal cancer (CRC).Methods:This study was based on the Screening Project of Early Diagnosis and Treatment of CRC in Jiashan county, Zhejiang province. After excluding participants with incomplete information, these with individual history of CRC, those with CRC, enteritis or ulcer, noticed through colonoscopy exam at baseline, a total of 25 894 participants were finally included. Cox proportional hazards regression model was used to analyze the association between colonoscopy and the incidence of CRC.Results:This study was followed up for 160 113 person-years with a median of 5.67 years. During the follow-up period, 127 of them developed the CRC. The incidence rates of CRC in participants, were 202.35 per 100 000 person-years, 40.93 per 100 000 person-years and 63.62 per 100 000 person-years, respectively among the following three groups: who did not take the colonoscopy, without colorectal lesions or with benign colorectal lesions noticed by the colonoscopy and the differences were statistically significant ( P<0.05). After adjusting for potential confounding factors, the HRs(95 %CI) of CRC were 0.24 (0.16-0.36) and 0.29 (0.17-0.49), among those who did not have or had colorectal lesions in the participants who underwent the colonoscopy. Stratified by anatomic site, age and sex, results showed that the associations among the aforementioned groups were relatively stable. Conclusion:Colonoscopy could effectively contribute to the reduction of CRC incidence in the high-risk population.

Objective: To explore the correlation between obesity and the risk of colorectal adenoma, so as to provide theoretic evidence for the intervention of the high-risk population for colorectal cancer. Methods: Based on the Screen Project of Early Diagnosis and Treatment of Colorectal Cancer in Jiashan County, from August 2012 to March 2018, the results of colonoscopy and body measurement information of the high-risk population for colorectal cancer were collected. According to the results of colonoscopy, 3 895 patients with colorectal adenoma and 11 232 healthy controls were enrolled. Multivariate logistic regression was used to analyze the correlation between overweight (body mass index (BMI) 24.0 to 27.9 kg/m²), obesity (BMI≥28.0 kg/m²) and the risk of colorectal adenoma. Results: After adjusting for gender and age, compared with that of individuals with normal weight (BMI 18.5 to 23.9 kg/m²), the risk of colorectal adenoma of obese patients increased by 36% (odds ratio (OR)=1.36, 95% confidence interval (CI) 1.18 to 1.56). After stratifing by gender, compared with that of individuals with normal weight, the risk of colorectal adenoma of obese males increased by 30% (OR=1.30, 95%CI 1.07 to 1.59), the risk of colorectal adenoma of overweight females and obese females increased by 15% (OR=1.15, 95%CI 1.01 to 1.31) and 40% (OR=1.40, 95%CI 1.14 to 1.71), respectively. After stratifing by age, compared with that of individuals with normal weight, the risk of colorectal adenoma of obese patients aged between 40 and 59 years increased by 31% (OR=1.31, 95%CI 1.07 to 1.61), and the risk of colorectal adenoma of overweight and obese patients aged between 60 and 74 years increased by 13% (OR=1.13, 95%CI 1.01 to 1.27) and 39% (OR=1.39, 95%CI 1.15 to 1.70), respectively. The results of subgroup analysis according to pathological types indicated that the risk of non-advanced adenoma and advanced adenoma of obese patients increased by 35% (OR=1.35, 95%CI 1.16 to 1.57) and 39% (OR=1.39, 95%CI 1.06 to 1.83), respectively. Conclusions Obesity is correlated with colorectal adenoma, which is more significant in women, individuals aged between 60 and 74 years and advanced adenoma. The intervention of high-risk population for colorectal cancer should include body mass control.