Marcus Ulrich, Mirandola Massimo, Schink Susanne B, Gios Lorenzo, Schmidt Axel J
Department for Infectious Diseases Epidemiology, Robert Koch Institute, Berlin, Germany.
Department of Diagnostics and Public Health, Infectious Diseases Section, University of Verona, Verona, Italy.
PLoS One. 2021 Mar 15;16(3):e0248582. doi: 10.1371/journal.pone.0248582. eCollection 2021.
BACKGROUND/OBJECTIVES: Many European countries reported increased numbers of syphilis, gonorrhoea and chlamydia diagnoses among men who have sex with men (MSM) in recent years. Behaviour changes and increased testing are thought to drive these increases.
In 2010 and 2017, two large online surveys for MSM in Europe (EMIS-2010, EMIS-2017) collected self-reported data on STI diagnoses in the previous 12 months, diagnostic procedures, STI symptoms when testing, number of sexual partners, and sexual behaviours such as condom use during the last intercourse with a non-steady partner in 46 European countries. Multivariate regression models were used to analyse factors associated with diagnoses of syphilis, gonorrhoea/chlamydia, and respective diagnoses classified as symptomatic and asymptomatic. If applicable, they included country-level screening rates.
Questions on STI diagnoses and sexual behaviours were answered by 156,018 (2010) and 125,837 (2017) participants. Between 2010 and 2017, overall diagnoses with gonorrhoea/chlamydia and syphilis increased by 76% and 83% across countries. Increases were more pronounced for asymptomatic compared to symptomatic infections. The proportion of respondents screened and the frequency of screening grew considerably. Condomless anal intercourse with the last non-steady partner rose by 62%; self-reported partner numbers grew. Increased syphilis diagnoses were largely explained by behavioural changes (including more frequent screening). Gonorrhoea/chlamydia increases were mainly explained by more screening and a change in testing performance. A country variable representing the proportion of men screened for asymptomatic infection was positively associated with reporting symptomatic gonorrhoea/chlamydia, but not syphilis.
DISCUSSION/CONCLUSION: The positive association of country-level screening rates with the proportion of symptomatic infections with gonorrhoea/chlamydia may indicate a paradoxical effect of screening on incidence of symptomatic infections. Treatment of asymptomatic men might render them more susceptible to new infections, while spontaneous clearance may result in reduced susceptibility. Before expanding screening programmes, evidence of the effects of screening and treatment is warranted.
背景/目的：近年来，许多欧洲国家报告称，男男性行为者（MSM）的梅毒、淋病和衣原体感染诊断病例数有所增加。行为改变和检测增加被认为是导致这些增加的原因。
2010年和2017年，针对欧洲男男性行为者开展了两项大型在线调查（EMIS - 2010、EMIS - 2017），收集了46个欧洲国家男男性行为者在过去12个月内自我报告的性传播感染（STI）诊断数据、诊断程序、检测时的STI症状、性伴侣数量以及性行为（如与非固定性伴侣的最后一次性交时的避孕套使用情况）。采用多变量回归模型分析与梅毒、淋病/衣原体感染诊断以及有症状和无症状的相应诊断相关的因素。如适用，模型纳入了国家层面的筛查率。
156,018名（2010年）和125,837名（2017年）参与者回答了关于性传播感染诊断和性行为的问题。2010年至2017年期间，各国淋病/衣原体感染和梅毒的总体诊断病例数分别增加了76%和83%。与有症状感染相比，无症状感染的增加更为明显。接受筛查的受访者比例和筛查频率大幅上升。与最后一位非固定性伴侣进行无保护肛交的比例上升了62%；自我报告的性伴侣数量增加。梅毒诊断病例数的增加在很大程度上可归因于行为改变（包括更频繁的筛查）。淋病/衣原体感染病例数的增加主要归因于更多的筛查和检测性能的变化。一个代表无症状感染筛查男性比例的国家变量与有症状淋病/衣原体感染的报告呈正相关，但与梅毒无关。
讨论/结论：国家层面的筛查率与有症状淋病/衣原体感染比例之间的正相关可能表明筛查对有症状感染发病率具有矛盾的影响。对无症状男性的治疗可能使他们更容易感染新的病原体，而自然清除可能导致易感性降低。在扩大筛查项目之前，有必要提供筛查和治疗效果的证据。
