Investigating the impact of Britain's HPV vaccination program to inform national public health interventions in the next decade

大多数子宫颈癌病例是由感染高危人乳头瘤病毒（HPV），特别是16型和18型HPV引起的。在英国，每年大约有3,200例新的子宫颈癌病例。然而，hpv相关的癌症，如宫颈癌，可以通过接种疫苗来预防。宫颈癌也可以通过常规宫颈癌筛查（向所有25岁及以上的妇女提供）及早发现和治疗异常细胞来预防。在英国，自2008年以来，HPV疫苗（2012年9月之前为二价Cervarix， 2012-2021年期间为四价Gardasil， 2021/2022年期间为9价Gardasil 9）已向所有12或13岁的女孩提供。该计划于2018年7月扩大到同一年龄段的男孩，并于2018年4月扩大到男男性行为者（MSM）。在英国和全球范围内的早期证据表明，疫苗接种计划在降低接种者的HPV患病率方面非常成功，因此可以预防HPV相关癌症，尽管目前尚不清楚其效果和吸收是否在人群中一致。目前还不清楚疫苗可预防的HPV类型（例如16/18型高危HPV）是否会与非疫苗类型或非疫苗类型的交叉保护发生“类型替代”。十年一次的国家性态度和生活方式调查（Natsal）研究是英国一项有代表性的性健康人口调查。Natsal-2（1999-2001）提供了用于疫苗接种规划设计的基线类型特异性HPV流行率，最近的Natsal研究（Natsal-3; 2010-12）捕获了最初的追赶HPV疫苗接种计划的早期效果和宫颈癌筛查吸收的不平等。来自Natsal-4（2022-23）的数据对于确定这些HPV干预措施在人群水平上的影响至关重要。该项目将使用Natsal-4研究的数据以及常规监测数据，分析与一系列人口和行为因素独特相关的特定类型的HPV患病率和HPV疫苗接种以及宫颈癌筛查，以评估对不平等和有针对性干预措施的机会的影响。在今后十年中，这些数据对于为国家公共卫生政策和估计一系列干预措施的数学模型提供信息至关重要，这些干预措施包括适应疫苗接种计划（例如单剂）、宫颈癌筛查以及向更年轻的年龄组推广。

Most cervical cancer cases are caused by infection with high-risk human papillomavirus (HPV), particularly HPV types 16 and 18. Annually, there are approximately 3,200 new cases of cervical cancer in the UK. However, HPV-related cancers, such as cervical cancer, can be prevented through vaccination. Cervical cancer can also be prevented through early detection and treatment of abnormal cells through routine cervical cancer screening (offered to all women aged 25 and over). In the UK, the HPV vaccine (bivalent Cervarix until September 2012, quadrivalent Gardasil from 2012-2021, and 9-valent Gardasil 9 in 2021/2022) has been offered to all girls aged 12 or 13 years since 2008. The program was expanded to include boys in the same age bracket in July 2018, as well as men who have sex with men (MSM) in April 2018. Early evidence, both in the UK and globally, suggests that the vaccination program has been highly successful at reducing HPV prevalence among vaccinated individuals and therefore preventing HPV-related cancers, though it is unclear whether the effects and uptake are consistent across population groups. It is also unclear whether 'type replacement' of the vaccine-preventable HPV types (e.g. high-risk HPV types 16/18) with non-vaccine types, or cross-protection of non-vaccine types, will occur. The decennial National Survey of Sexual Attitudes and Lifestyles (Natsal) study is a representative population survey on sexual health in Britain. Natsal-2 (1999-2001) provided baseline type-specific HPV prevalence used to inform the design of the vaccination program, and the most recent Natsal study (Natsal-3; 2010-12) captured the early effects of the initial catch-up HPV vaccination program and inequalities in cervical cancer screening uptake. Data from Natsal-4 (2022-23) will be crucial to determine the effect of these HPV interventions at a population level. This project will use data from the Natsal-4 study, as well as routine surveillance data, to analyse type-specific HPV prevalence and uptake of HPV vaccination and cervical cancer screening uniquely linked to a range of demographic and behavioural factors to assess impact on inequalities and opportunities for targeted interventions. Over the next ten years, these data will be critical to inform national public health policy and mathematical models estimating a range of interventions, including adaptations to vaccine schedule (e.g. to single dose), cervical cancer screening, and roll out to younger age groups.