Division of Epidemiology & Community Health, School of Public Health, University of Minnesota Twin Cities, Minneapolis, MN, USA.
Li Ka Shing Centre for Health Information and Discovery, Oxford, UK.
Sex Health. 2023 Apr;20(2):126-133. doi: 10.1071/SH22163.
Age-based sexual mixing patterns in men who have sex with men (MSM) can greatly inform strategic allocation of intervention resources to subsets of the population for the purpose of preventing the greatest number of new HIV infections.
Egocentric network data collected from MSM participating in annual HIV sentinel surveillance surveys were used to assess age-dependent mixing and to explore its epidemiological implications on the risk of HIV transmission risk (among those HIV-infected) and HIV acquisition risk (among those not infected).
Mixing in this sample of 1605 Chinese MSM is relatively age assortative (the average of values expressing the degree of preferential mixing were 2.01 in diagonal cells vs 0.87 in off-diagonal cells). Expected numbers of HIV acquisition were highest in the 20-24years age group; those for HIV transmissions were highest among 25-29year olds. The risk of both acquisition and transmission was highest in age groups that immediately follow the most commonly reported ages of sexual debut in this population (i.e. age 20).
These findings suggest that combination prevention resources should be targeted at younger MSM who are at higher risk of both transmission and acquisition. Programs may also do well to target even younger age groups who have not yet debuted in order to establish prevention effects before risky sexual behaviours begin. More research on optimal strategies to access these harder-to-reach subsets of the MSM population is needed. Findings also support ongoing efforts for public health practitioners to collect network data in key populations to support more empirically driven strategies to target prevention resources.
男男性行为者（MSM）的年龄相关的性混合模式可以为干预资源在人口亚群中的战略分配提供重要信息，目的是预防新的 HIV 感染数量达到最大。
从参加年度 HIV 哨点监测调查的 MSM 中收集的自我中心网络数据用于评估年龄依赖的混合，并探讨其对 HIV 传播风险（在那些 HIV 感染者中）和 HIV 感染风险（在那些未感染者中）的流行病学意义。
在这个 1605 名中国 MSM 的样本中，混合相对年龄聚集（表示优先混合程度的值的平均值在对角单元格中为 2.01，在非对角单元格中为 0.87）。预计在 20-24 岁年龄组中 HIV 感染的数量最高；在 25-29 岁年龄组中 HIV 传播的数量最高。在该人群中首次性行为最常见的年龄组之后的年龄组中，感染和传播的风险最高（即 20 岁）。
这些发现表明，应将组合预防资源针对那些感染和传播风险较高的年轻 MSM。为了在危险性行为开始之前建立预防效果，计划也可以很好地针对尚未首次性行为的更年轻年龄组。需要对接触这些更难接触的 MSM 人群的亚群的最佳策略进行更多研究。这些发现还支持公共卫生从业人员继续收集网络数据的努力，以支持更具经验驱动的策略来针对预防资源。
