BACKGROUND Young people are at particularly high risk of acquiring sexually transmitted infections (STIs). We conducted a trial to investigate the effect of a community-based intervention that included STI screening among youth on population-level prevalence of STIs in Zimbabwe. METHODS STICH was a parallel-arm, cluster-randomised controlled trial nested within CHIEDZA, a trial of community-based integrated HIV and sexual and reproductive health services for youth in Zimbabwe. STICH was conducted in Harare and Bulawayo provinces with eight clusters in each province, randomised 1:1 to control (existing health services) or to the intervention: community-based screening and treatment for Chlamydia trachomatis and Neisseria gonorrhoeae (males and females) and Trichomonas vaginalis (females only) offered over 12 months to intervention cluster residents aged 16-24 years who were attending CHIEDZA. Outcomes were ascertained through a population-level survey immediately after the intervention period, which included young people aged 18-24 years who lived in randomly selected households in each of the 16 clusters. The primary outcome was population prevalence of any (one or more) of the three STIs; secondary outcomes were prevalence of each of the three STIs. The STICH trial is registered with ISRCTN registry, ISRCTN15013425, and the CHIEDZA trial is registered with ClinicalTrials.gov, NCT03719521. FINDINGS From Oct 6, 2021, to March 8, 2022, 6361 randomly sampled young people were recruited into the outcome survey (median age 20 years [IQR 19-22], 3500 female and 2101 male, 3066 in intervention clusters and 3295 in control clusters). 5601 participants were included in the primary outcome analysis (2756 in intervention clusters and 2845 in control clusters). In the intervention clusters, 612 (22·2%) of 2756 participants reported that they had attended CHIEDZA and 298 (10·8%) had been tested for C trachomatis and N gonorrhoeae. In the control clusters, 113 (4·0%) of 2845 participants had attended CHIEDZA and 40 (1·4%) had been tested for C trachomatis and N gonorrhoeae. In the outcome survey, the cluster-level geometric mean prevalence of the primary outcome (any of C trachomatis, N gonorrhoeae, and T vaginalis) was 19·07% (geometric standard deviation [GSD] 1·20) in the intervention arm versus 19·95% (GSD 1·10) in the control arm (risk ratio [RR] 0·93 [95% CI 0·78-1·10]; p=0·35). There was no difference between arms in geometric mean prevalence of C trachomatis (12·86% [GSD 1·14] in the intervention arm vs 12·94% [GSD 1·15] in the control arm, RR 0·97 [95% CI 0·84-1·11]; p=0·60) or T vaginalis (7·06% [GSD 1·48] vs 6·20% [1·38], RR 1·09 [95% CI 0·74-1·60]; p=0·66). N gonorrhoeae prevalence was significantly lower in the intervention arm, with a 43% risk reduction (geometric mean 1·65% [GSD 1·77] vs 2·87% [1·43], RR 0·57 [95% CI 0·34-0·96]; p=0·036). INTERPRETATION Our study showed high population prevalence of curable STIs. Community-based STI screening appeared to reduce population-level prevalence of N gonorrhoeae, but not of C trachomatis or T vaginalis, probably due to low intervention coverage. Future research is needed on the effects of screening interventions on morbidity, antimicrobial resistance, and re-infection rates. FUNDING Medical Research Council, Economic and Social Research Council, Department for International Development, National Institute for Health and Care Research, and the Wellcome Trust.

中文翻译：

---

基于社区的性传播感染干预对津巴布韦青年人口水平患病率 （STICH） 的影响：一项整群随机试验。


背景 年轻人获得性传播感染 （STI） 的风险特别高。我们进行了一项试验，以调查基于社区的干预措施（包括在青少年中进行 STI 筛查）对津巴布韦人群水平 STI 患病率的影响。方法 STICH 是一项平行臂、整群随机对照试验，嵌套在 CHIEDZA 中，这是一项针对津巴布韦青年的社区综合 HIV 和性与生殖健康服务的试验。STICH 在哈拉雷省和布拉瓦约省进行，每个省有 8 个集群，以 1：1 的比例随机分配至对照（现有卫生服务）或干预组：以社区为基础的沙眼衣原体和淋病奈瑟菌（男性和女性）和阴道毛滴虫（仅限女性）的筛查和治疗，为期 12 个月，提供给参加 CHIEDZA 的 16-24 岁的干预集群居民。干预期后立即通过人口水平调查确定结果，其中包括 18 个集群中随机选择的 24-16 个集群中随机选择的家庭中的年轻人。主要结局是三种 STI 中任何（一种或多种）的人群流行率;次要结局是 3 种 STI 的患病率。STICH 试验已在 ISRCTN15013425 的 ISRCTN 注册处注册，CHIEDZA 试验已在 ClinicalTrials.gov NCT03719521注册。结果从 2021 年 10 月 6 日至 2022 年 3 月 8 日，随机抽样的 6361 名年轻人被招募到结果调查中（中位年龄 20 岁 [IQR 19-22]，3500 名女性和 2101 名男性，干预集群 3066 名，对照组 3295 名）。主要结局分析纳入了 5601 名参与者 （干预组 2756 名，对照组 2845 名）。 在干预集群中，2756 名参与者中有 612 名 （22·2%） 报告他们参加了 CHIEDZA，298 名 （10·8%） 接受了沙眼衣原体和淋病奈瑟菌检测。在对照组中，2845 名参与者中有 113 名 （4·0%） 参加了 CHIEDZA，40 名 （1·4%） 接受了沙眼衣原体和淋病奈瑟菌检测。在结果调查中，干预组主要结果（沙眼衣原体、淋病奈瑟菌和阴道毛滴虫中的任何一种）的整群水平几何平均患病率为 19·07%（几何标准差 [GSD] 1·20），而对照组为 19·95% （GSD 1·10）（风险比 [RR] 0·93 [95% CI 0·78-1·10];p=0·35）。沙眼衣原体的几何平均患病率（干预组为 12·86% [GSD 1·14] vs 对照组为 12·94% [GSD 1·15]，RR 0·97 [95% CI 0·84-1·11];p=0·60）或阴道毛滴虫（7·06% [GSD 1·48] vs 6·20% [1·38]，两组之间没有差异。 RR 1·09 [95% CI 0·74-1·60];p=0·66）。干预组淋病奈瑟菌患病率显著降低，风险降低 43% （几何平均值 1·65% [GSD 1·77] vs 2·87% [1·43]，RR 0·57 [95% CI 0·34-0·96];p=0·036）。解释 我们的研究表明，可治愈的 STI 的人群患病率很高。基于社区的 STI 筛查似乎降低了人群层面的淋病奈瑟菌患病率，但没有降低沙眼衣原体或阴道毛滴虫的患病率，这可能是由于干预覆盖率低。需要进一步研究筛查干预对发病率、抗菌素耐药性和再感染率的影响。资助医学研究委员会、经济和社会研究委员会、国际发展部、国家健康与护理研究所和惠康信托基金。