Abstract:
BackgroundIn 2022 and 2023, a global outbreak of mpox affected mostly gay, bisexual and other men having sex with men (GBMSM). Outbreak control in the Netherlands included isolation, quarantine, post-exposure prophylaxis vaccination and primary preventive vaccination (PPV).AimWe describe the course of the outbreak, the vaccination programme, vaccine effectiveness (VE) of full vaccination against symptomatic disease, and trends in behaviour to generate hypotheses about factors that influenced the outbreak\'s decline.MethodsIn this observational study, we collected data from public health services on notified cases, number of PPV invitations and PPV doses administered. We calculated PPV uptake and coverage. Trends in behavioural data of GBMSM visiting sexual health centres were analysed for all consultations in 2022. We estimated VE using the screening method.ResultsUntil 31 December 2023, 1,294 mpox cases were reported. The outbreak peaked in early July 2022 and then declined sharply. PPV started on 25 July 2022; in total 29,851 doses were administered, 45.8% received at least one dose, 35.4% were fully vaccinated. The estimated VE was 68.2% (95% CI 4.3-89.5%). We did not observe an evident decrease in high-risk behaviour.DiscussionIt is unlikely that PPV was a driver of the outbreak\'s decline, as incidence started to decline well before the start of the PPV programme. The possible impact of behavioural change could not be demonstrated with the available indicators, however, the data had limitations, hampering interpretation. We hypothesise that infection-induced immunity in high-risk groups was an important factor explaining the decline.
摘要:
背景在2022年和2023年,全球爆发的水痘主要影响同性恋,双性恋和其他男性与男性发生性关系(GBMSM)。荷兰的疫情控制包括隔离,检疫,暴露后预防性疫苗接种和初级预防性疫苗接种(PPV)。我们描述了爆发的过程,疫苗接种计划,针对有症状疾病的全面疫苗接种的疫苗有效性(VE),和行为趋势,以产生关于影响疫情下降的因素的假设。方法在这项观察性研究中,我们从公共卫生服务机构收集了通报病例的数据,给予的PPV邀请和PPV剂量的数量。我们计算了PPV摄取和覆盖率。在2022年的所有咨询中,对GBMSM访问性健康中心的行为数据趋势进行了分析。我们使用筛选方法估计了VE。结果截至2023年12月31日,共报告1,294例水痘病例。疫情在2022年7月初达到峰值,随后大幅下降。PPV于2022年7月25日开始;总共施用了29,851剂,45.8%的人接受了至少一次剂量,35.4%完全接种疫苗。估计VE为68.2%(95%CI4.3-89.5%)。我们没有观察到高风险行为的明显减少。讨论PPV不太可能是疫情下降的驱动因素,由于发病率在PPV计划开始之前就开始下降。行为改变的可能影响无法用现有指标来证明,然而,数据有局限性,妨碍解释。我们假设高危人群中感染诱导的免疫力是解释这种下降的重要因素。