Sources of HIV infections among MSM with a migration background: a viral phylogenetic case study in Amsterdam, the Netherlands

Alexandra Blenkinsop; Nikos Pantazis; Evangelia Georgia Kostaki; Lysandros Sofocleous; Ard van Sighem; Daniela Bezemer; Thijs van de Laar; Marc van der Valk; Peter Reiss; Godelieve de Bree; Oliver Ratmann

arXiv · 2401.08308

Sources of HIV infections among MSM with a migration background: a viral phylogenetic case study in Amsterdam, the Netherlands

Alexandra Blenkinsop·Nikos Pantazis·Evangelia Georgia Kostaki·Lysandros Sofocleous·Ard van Sighem·Daniela Bezemer·Thijs van de Laar·Marc van der Valk·Peter Reiss·Godelieve de Bree·Oliver Ratmann

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Abstract

Background: Men and women with a migration background comprise an increasing proportion of incident HIV cases across Western Europe. Several studies indicate a substantial proportion acquire HIV post-migration. Methods: We used partial HIV consensus sequences with linked demographic and clinical data from the opt-out ATHENA cohort of people with HIV in the Netherlands to quantify population-level sources of transmission to Dutch-born and foreign-born Amsterdam men who have sex with men (MSM) between 2010-2021. We identified phylogenetically and epidemiologically possible transmission pairs in local transmission chains and interpreted these in the context of estimated infection dates, quantifying transmission dynamics between sub-populations by world region of birth. Results: We estimate the majority of Amsterdam MSM who acquired their infection locally had a Dutch-born Amsterdam MSM source (56% [53-58%]). Dutch-born MSM were the predominant source population of infections among almost all foreign-born Amsterdam MSM sub-populations. Stratifying by two-year intervals indicated shifts in transmission dynamics, with a majority of infections originating from foreign-born MSM since 2018, although uncertainty ranges remained wide. Conclusions: In the context of declining HIV incidence among Amsterdam MSM, our data suggest whilst native-born MSM have predominantly driven transmissions in 2010-2021, the contribution from foreign-born MSM living in Amsterdam is increasing.

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Alexandra Blenkinsop, Nikos Pantazis, Evangelia Georgia Kostaki, Lysandros Sofocleous, Ard van Sighem, Daniela Bezemer, Thijs van de Laar, Marc van der Valk, Peter Reiss, Godelieve de Bree, Oliver Ratmann. 2024-01-16. Sources of HIV infections among MSM with a migration background: a viral phylogenetic case study in Amsterdam, the Netherlands. https://arxiv.org/abs/2401.08308

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