Infectious Disease Prevention and Control, Chongqing Municipal Center for Disease Control and Prevention, Chongqing, China.
School of Public Health, Southwest Medical University, Luzhou, Sichuan, China.
Hum Vaccin Immunother. 2024 Dec 31;20(1):2363076. doi: 10.1080/21645515.2024.2363076. Epub 2024 Jun 7.
To optimize seasonal influenza control and prevention programs in regions with potentially complicated seasonal patterns. Descriptive epidemiology was used to analyze the etiology of influenza, and chi-square tests were used to compare the epidemic patterns among different influenza virus types and subtypes/lineages. From January 2010 to December 2019, a total of 63,626 ILI cases were reported in Chongqing and 14,136 (22.22%) were laboratory-confirmed influenza cases. The proportions of specimens positive for influenza A and influenza B were 13.32% (8,478/63,626) and 8.86% (5,639/63,626), respectively. The proportion of positive specimens for influenza A reached the highest in winter (23.33%), while the proportion of positive specimens for influenza B reached the highest in spring (11.88%). Children aged 5-14 years old had the highest proportion of positive specimens for influenza. The influenza virus types/subtypes positive was significantly different by seasons and age groups (<.001), but not by gender ( = .436). The vaccine strains were matched to the circulating influenza virus strains in all other years except for 2018 (vaccine strain was B/Colorado/06/2017; circulating strain was B/Yamagata). The study showed significant variations in epidemic patterns, including seasonal epidemic period and age distributions, among different influenza types, subtypes/lineages in Chongqing. Influenza vaccines matched to the circulating influenza virus strain in nine of the ten years. To prevent and mitigate the influenza outbreaks in this area, high risk population, especially children aged 5-14 years, are encouraged to get vaccinated against influenza before the epidemic seasons.
为优化潜在季节模式复杂地区的季节性流感防控计划。采用描述性流行病学方法分析流感病因，采用卡方检验比较不同流感病毒型别和亚型/谱系的流行模式。2010 年 1 月至 2019 年 12 月，重庆市共报告流感样病例（ILI）63626 例，实验室确诊流感病例 14136 例（22.22%）。流感 A 型和 B 型标本阳性率分别为 13.32%（8478/63626）和 8.86%（5639/63626）。流感 A 型阳性标本比例冬季最高（23.33%），流感 B 型阳性标本比例春季最高（11.88%）。5-14 岁儿童流感阳性标本比例最高。流感病毒型别/亚型在不同季节和年龄组的阳性率存在显著差异（<0.001），但在不同性别间差异无统计学意义（=0.436）。除 2018 年（疫苗株为 B/Colorado/06/2017，流行株为 B/Yamagata）外，其余年份疫苗株与流行株均匹配。研究表明，重庆市不同流感型别、亚型/谱系的流行模式存在显著差异，包括季节性流行期和年龄分布。在十年中的九年，流感疫苗株与流行株相匹配。为预防和减轻该地区流感疫情，鼓励高风险人群，尤其是 5-14 岁儿童，在流行季节前接种流感疫苗。
