In this paper, we study a single serotype transmission model of dengue to determine the optimal vaccination age for Dengvaxia. The transmission dynamics are modelled with an age-dependent force of infection. The force of infection for each serotype is derived from the serological profile of dengue in Brazil without serotype distinction and from serotype-specific reported cases. The risk due to an infection is measured by the probability of requiring hospitalization based on Brazilian Ministry of Health data. The optimal vaccination age is determined for any number and combination of the four distinct dengue virus serotypes DENv1–4. The lifetime expected risk is adapted to include antibody dependent enhancement (ADE) and permanent cross-immunity after two heterologous infections. The risk is assumed to be serostatus-dependent. The optimal vaccination age is computed for constant, serostatus-specific vaccine efficacies. Additionally, the vaccination age is restricted to conform to the licence of Dengvaxia in Brazil and the achievable and minimal lifetime expected risks are compared. The optimal vaccination age obtained for the risk of hospitalization varies significantly with the assumptions relating to ADE and cross-immunity. Risk-free primary infections lead to higher optimal vaccination ages, as do asymptomatic third and fourth infections. Sometimes vaccination is not recommended at all, e.g. for any endemic area with a single serotype if primary infections are risk-free. Restricting the vaccination age to Dengvaxia licensed ages mostly leads to only a slightly higher lifetime expected risk and the vaccine should be administered as close as possible to the optimal vaccination age.

中文翻译：

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根据血清学数据得出的血清型特异性感染力，巴西登革热疫苗接种的最佳年龄

在本文中，我们研究了登革热的单一血清型传播模型，以确定登革热的最佳疫苗接种年龄。传播动力学是用年龄相关的感染力建模的。每种血清型的感染力来自巴西登革热的血清学特征，没有血清型区分，也来自特定血清型的报告病例。根据巴西卫生部的数据，通过需要住院治疗的概率来衡量感染风险。对于四种不同的登革热病毒血清型 DENv1-4 的任意数量和组合，确定最佳疫苗接种年龄。终生预期风险适用于包括抗体依赖性增强 (ADE) 和两次异源感染后的永久性交叉免疫。假定风险与血清状态有关。最佳疫苗接种年龄是针对恒定的、血清状态特异性疫苗效力计算的。此外，疫苗接种年龄被限制为符合巴西 Dengvaxia 的许可，并且比较了可实现的和最小的终生预期风险。针对住院风险获得的最佳疫苗接种年龄因与 ADE 和交叉免疫相关的假设而异。无风险的原发感染导致更高的最佳疫苗接种年龄，无​​症状的第三次和第四次感染也是如此。有时根本不推荐接种疫苗，例如，如果原发感染是无风险的，那么对于任何具有单一血清型的流行地区。