摘要目的:了解15~17岁校外青少年艾滋病病毒（HIV）感染者的流行特征，为制定校外青少年艾滋病防控策略提供依据。方法:资料来源于我国艾滋病综合防治信息系统，筛选2011-2019年确诊时年龄为15~17岁校外青少年HIV感染者。描述社会人口学特征、感染途径和跨省流动等情况，采用 χ 2检验进行组间比较。运用Joinpoint 4.9.0 软件计算粗新发现率年度变化百分比（annual percent change，APC）并做Joinpoint回归模型的时间趋势检验。运用Excel 2019和SPSS 22.0软件进行数据整理和统计学分析。 结果:2011-2019年我国共报告15~17岁校外青少年HIV感染者4 919例，占报告15~17岁HIV感染者的63.4%（4 919/7 757），时间趋势分析结果显示，2011-2015年该人群粗新发现率呈增长趋势（APC=36.4%， P<0.001），2016年及以后保持平稳趋势（APC=2.5%， P=0.173）。该人群HIV感染者跨省流动占13.9%（684/4 919）。相比于非跨省流动病例，跨省流动病例中男性、务工人员、样本来源为羁押场所、男男性传播及注射吸毒传播的占比高。15~17岁校外青少年HIV感染者主要通过性途径传播，其中2019年，66.5%（280/421）男性通过男男性传播感染，97.8%（182/186）的女性通过异性性传播感染。 结论:15~17岁校外青少年主要通过性途径感染HIV，性与生殖健康意识薄弱，且流动性较大，应重视该人群的性与生殖健康和艾滋病防治教育，提高其自我防护意识，为其提供适应需求的防治服务。

abstractsObjective:To understand the epidemiological characteristics of HIV-infected adolescents outside school in China and provide reference to targeted prevention and control of HIV infection in this population.Methods:All the HIV-infected adolescents aged 15-17 years outside school reported during 2011-2019 were included this study. The information about their demographics, transmission routes and migration were collected from HIV/AIDS Comprehensive Response Information Management System. The χ2 test was done for comparison among groups. The Joinpoint 4.9.0 software was applied to the annual percent change (APC) for time trends analysis using the Joinpoint regression model. The Excel 2019 and SPSS 22.0 software were used for data cleaning and statistical analysis. Results:A total of 4 919 HIV-infected adolescents aged 15-17 years outside school were reported accumulatively in China between 2011 and 2019, accounting for 63.4% (4 919/7 757) of total reported HIV-infected cases in this age group. Analysis on trend revealed that the new HIV infection diagnosis rate has become stable since 2016 (APC=2.5%, P=0.173) after the increase between 2011 and 2015 (APC=36.4%, P<0.001). The migration across provinces was discovered in 13.9% (684/4 919) of the HIV-infected adolescents outside school. Males, workers, and those diagnosed in detention centers or transmitted by injecting drugs or homosexual contacts accounted for a larger proportion in migrated cases compared with non-migrated cases. The adolescents outside school mainly got HIV infected by sexual contacts route, in which 66.5% (280/421) of the males were infected by homosexual contacts, while 97.8% (182/186) of the females were infected by heterosexual contacts in 2019. Conclusions:HIV-infected adolescents aged 15-17 years outside school were mainly infected by sexual contacts. However, adolescents outside school have low awareness of sexual health and high mobility, to whom close attention should be paid to improve their awareness of sexual health and to provide them with appropriate HIV infection prevention and treatment service.