Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom.
PLoS One. 2013 Sep 26;8(9):e75552. doi: 10.1371/journal.pone.0075552. eCollection 2013.
Recent trials have indicated that women with prior exposure to Human papillomavirus (HPV) subtypes 16/18 receive protection against reinfection from the HPV vaccines. However, many of the original models investigating the cost effectiveness of different vaccination strategies for the protection of cervical cancer assumed, based on the trial results at that time, that these women received no protection. We developed a deterministic, dynamic transmission model that incorporates the vaccine-induced protection of women with prior exposure to HPV. The model was used to estimate the cost effectiveness of progressively extending a vaccination programme using the bivalent vaccine to older age groups both with and without protection of women with prior exposure. We did this under a range of assumptions on the level of natural immunity. Our modelling projections indicate that including the protection of women with prior HPV exposure can have a profound effect on the cost effectiveness of vaccinating adults. The impact of this protection is inversely related to the level of natural immunity. Our results indicate that adult vaccination strategies should potentially be reassessed, and that it is important to include the protection of non-naive women previously infected with HPV in future studies. Furthermore, they also highlight the need for a more thorough investigation of this protection.
最近的试验表明，先前接触过 HPV 亚型 16/18 的女性可以通过 HPV 疫苗获得免受再感染的保护。然而，许多最初研究不同疫苗接种策略在预防宫颈癌成本效益的模型都基于当时的试验结果假设，这些女性没有得到任何保护。我们开发了一个确定性的、动态的传播模型，其中纳入了先前接触 HPV 的女性的疫苗诱导保护。该模型用于估计使用二价疫苗逐步向更年长的年龄组扩展疫苗接种计划的成本效益，同时考虑和不考虑对先前接触 HPV 的女性的保护。我们在一系列关于自然免疫力水平的假设下进行了这项研究。我们的建模预测表明，包括先前接触 HPV 的女性的保护可以对成年人接种疫苗的成本效益产生深远影响。这种保护的效果与自然免疫力水平成反比。我们的结果表明，成人疫苗接种策略可能需要重新评估，并且在未来的研究中，纳入对先前感染 HPV 的非初染女性的保护非常重要。此外，它们还强调了需要更深入地研究这种保护。
