Department of Vaccination and Immune Protection, National Institute for Health and Welfare (THL), Helsinki, Finland.
PLoS One. 2013 Aug 29;8(8):e72088. doi: 10.1371/journal.pone.0072088. eCollection 2013.
The development of high-risk human papillomavirus (hrHPV) infection to cervical cancer is a complicated process. We considered solely hrHPV infections, thus avoiding the confounding effects of disease progression, screening, and treatments. To analyse hrHPV epidemiology and to estimate the overall impact of vaccination against infections with hrHPVs, we developed a dynamic compartmental transmission model for single and multiple infections with 14 hrHPV types. The infection-related parameters were estimated using population-based sexual behaviour and hrHPV prevalence data from Finland. The analysis disclosed the important role of persistent infections in hrHPV epidemiology, provided further evidence for a significant natural immunity, and demonstrated the dependence of transmission probability estimates on the model structure. The model predicted that vaccinating girls at 80% coverage will result in a 55% reduction in the overall hrHPV prevalence and a higher 65% reduction in the prevalence of persistent hrHPV infections in females. In males, the reduction will be 42% in the hrHPV prevalence solely by the herd effect from the 80% coverage in girls. If such high coverage among girls is not reached, it is still possible to reduce the female hrHPV prevalence indirectly by the herd effect if also boys are included in the vaccination program. On the other hand, any herd effects in older unvaccinated cohorts were minor. Limiting the epidemiological model to infection yielded improved understanding of the hrHPV epidemiology and of mechanisms with which vaccination impacts on hrHPV infections.
高危型人乳头瘤病毒（hrHPV）感染发展为宫颈癌是一个复杂的过程。我们仅考虑了 hrHPV 感染，从而避免了疾病进展、筛查和治疗的混杂影响。为了分析 hrHPV 的流行病学，并评估针对 hrHPV 感染的疫苗接种的总体影响，我们针对 14 种 hrHPV 型的单次和多次感染开发了一个动态房室传输模型。使用基于人群的性行为和芬兰的 hrHPV 流行率数据来估计与感染相关的参数。分析揭示了持续性感染在 hrHPV 流行病学中的重要作用，进一步证明了自然免疫力的显著作用，并表明了传输概率估计对模型结构的依赖性。该模型预测，如果以 80%的覆盖率为女孩接种疫苗，将使总体 hrHPV 流行率降低 55%，女性持续性 hrHPV 感染的流行率降低 65%。在男性中，仅通过女孩 80%覆盖率的群体效应，hrHPV 流行率就会降低 42%。如果无法达到如此高的女孩覆盖率，通过群体效应仍然有可能间接地降低女性的 hrHPV 流行率，如果也将男孩纳入疫苗接种计划。另一方面，任何针对年龄较大的未接种人群的群体效应都很小。将流行病学模型限制在感染范围内，可以更好地理解 hrHPV 流行病学以及疫苗接种对 hrHPV 感染的影响机制。
