Background: More than 300 cities including the city of Amsterdam in the Netherlands have joined the UNAIDS Fast-Track Cities initiative, committing to accelerate their HIV response and end the AIDS epidemic in cities by 2030. To support this commitment, we aimed to estimate the number and proportion of Amsterdam HIV infections that originated within the city, from Amsterdam residents. We also aimed to estimate the proportion of recent HIV infections during the 5-year period 2014-2018 in Amsterdam that remained undiagnosed.
Methods: We located diagnosed HIV infections in Amsterdam using postcode data (PC4) at time of registration in the ATHENA observational HIV cohort, and used HIV sequence data to reconstruct phylogeographically distinct, partially observed Amsterdam transmission chains. Individual-level infection times were estimated from biomarker data, and used to date the phylogenetically observed transmission chains as well as to estimate undiagnosed proportions among recent infections. A Bayesian Negative Binomial branching process model was used to estimate the number, size and growth of the unobserved Amsterdam transmission chains from the partially observed phylogenetic data.
Results: Between January 1 2014 and May 1 2019, there were 846 HIV diagnoses in Amsterdam residents, of whom 516 (61%) were estimated to have been infected in 2014-2018. The rate of new Amsterdam diagnoses since 2014 (104 per 100,000) remained higher than the national rates excluding Amsterdam (24 per 100,000), and in this sense Amsterdam remained a HIV hotspot in the Netherlands. An estimated 14% [12-16%] of infections in Amsterdan MSM in 2014-2018 remained undiagnosed by May 1 2019, and 41% [35-48%] in Amsterdam heterosexuals, with variation by region of birth. An estimated 68% [61-74%] of Amsterdam MSM infections in 2014-2018 had an Amsterdam resident as source, and 57% [41-71%] in Amsterdam heterosexuals, with heterogeneity by region of birth. Of the locally acquired infections, an estimated 43% [37-49%] were in foreign-born MSM, 41% [35-47%] in Dutch-born MSM, 10% [6-18%] in foreign-born heterosexuals, and 5% [2-9%] in Dutch-born heterosexuals. We estimate the majority of Amsterdam MSM infections in 2014-2018 originated in transmission chains that pre-existed by 2014.
Conclusions: This combined phylogenetic, epidemiologic, and modelling analysis in the UNAIDS Fast-Track City Amsterdam indicates that there remains considerable potential to prevent HIV infections among Amsterdam residents through city-level interventions. The burden of locally acquired infection remains concentrated in MSM, and both Dutch-born and foreign-born MSM would likely benefit most from intensified city-level interventions.
Funding: This study received funding as part of the H-TEAM initiative from Aidsfonds (project number P29701). The H-TEAM initiative is being supported by Aidsfonds (grant number: 2013169, P29701, P60803), Stichting Amsterdam Dinner Foundation, Bristol-Myers Squibb International Corp. (study number: AI424-541), Gilead Sciences Europe Ltd (grant number: PA-HIV-PREP-16-0024), Gilead Sciences (protocol numbers: CO-NL-276-4222, CO-US-276-1712, CO-NL-985-6195), and M.A.C AIDS Fund.
Anonymised data are available in the public Github repository https://github.com/alexblenkinsop/locally.acquired.infections. These include aggregated time-to-diagnosis data, and reconstructed phylogenetic trees labelled by one of the 9 Amsterdam risk groups and year of sequence sample. Statistical information or data for separate research purposes from the ATHENA cohort can be requested by submitting a research proposal (https://www.hiv-monitoring.nl/english/research/research-projects/). HIV physicians can review the data of their own treatment centre and compare these data with the full cohort through an online report builder. For correspondence: firstname.lastname@example.org.
- Alexandra Blenkinsop
- Godelieve J de Bree
- Oliver Ratmann
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Human subjects: As from 2002 ATHENA is managed by Stichting HIV Monitoring, the institution appointed by the Dutch Ministry of Public health, Welfare and Sport for the monitoring of people living with HIV in the Netherlands. People entering HIV care receive written material about participation in the ATHENA cohort and are informed by their treating physician on the purpose of data collection, thereafter they can consent verbally or elect to opt-out. Data are pseudonymised before being provided to investigators and may be used for scientific purposes. A designated data protection officer safeguards compliance with the European General Data Protection Regulation (Boender et al. 2018).
- Joshua T Schiffer, Fred Hutchinson Cancer Research Center, United States
- Received: December 17, 2021
- Accepted: August 1, 2022
- Accepted Manuscript published: August 3, 2022 (version 1)
© 2022, Blenkinsop et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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