Drivers of HIV-1 transmission: The Portuguese case

PLoS One. 2019 Sep 30;14(9):e0218226. doi: 10.1371/journal.pone.0218226. eCollection 2019.

Abstract

Background: Portugal has one of the most severe HIV-1 epidemics in Western Europe. Two subtypes circulate in parallel since the beginning of the epidemic. Comparing their transmission patterns and its association with transmitted drug resistance (TDR) is important to pinpoint transmission hotspots and to develop evidence-based treatment guidelines.

Methods: Demographic, clinical and genomic data were collected from 3599 HIV-1 naive patients between 2001 and 2014. Sequences obtained from drug resistance testing were used for subtyping, TDR determination and transmission clusters (TC) analyses.

Results: In Portugal, transmission of subtype B was significantly associated with young males, while transmission of subtype G was associated with older heterosexuals. In Portuguese originated people, there was a decreasing trend both for prevalence of subtype G and for number of TCs in this subtype. The active TCs that were identified (i.e. clusters originated after 2008) were associated with subtype B-infected males residing in Lisbon. TDR was significantly different when comparing subtypes B (10.8% [9.5-12.2]) and G (7.6% [6.4-9.0]) (p = 0.001).

Discussion: TC analyses shows that, in Portugal, the subtype B epidemic is active and fueled by young male patients residing in Lisbon, while transmission of subtype G is decreasing. Despite similar treatment rates for both subtypes in Portugal, TDR is significantly different between subtypes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Antiretroviral Therapy, Highly Active
  • Drug Resistance, Viral
  • Female
  • Follow-Up Studies
  • Genotype
  • HIV Infections / drug therapy
  • HIV Infections / epidemiology*
  • HIV Infections / transmission*
  • HIV Infections / virology
  • HIV-1* / drug effects
  • HIV-1* / genetics
  • Humans
  • Male
  • Odds Ratio
  • Portugal / epidemiology
  • Prevalence
  • Public Health Surveillance
  • Sex Factors
  • Socioeconomic Factors
  • Young Adult

Grants and funding

This study was supported by European Funds through grant ‘Bio-Molecular and Epidemiological Surveillance of HIV Transmitted Drug Resistance, Hepatitis Co-Infections and Ongoing Transmission Patterns in Europe - BEST HOPE - (project funded through HIVERA: Harmonizing Integrating Vitalizing European Research on HIV/Aids, grant 249697)’ to ABA; by L’'Oréal Portugal Medals of Honor for Women in Science 2012 (financed through L’'Oréal Portugal, Comissão Nacional da Unesco and Fundação para a Ciência e Tecnologia (FCT - http://www.fct.pt)) to ABA; by FCT for funds to GHTM-UID/Multi/04413/2013; by the MigrantHIV project (financed by FCT: PTDC/DTP-EPI/7066/2014 to ABA; by Gilead Génese HIVLatePresenters to ABA; by the National Nature Science Foundation of China (31571368) to GL; by the Innovation-driven Project of Central South University (2016CX031) to GL; by the Fonds voor Wetenschappelijk Onderzoek – Flanders (FWO) grant G.0692.14, and G.0611.09N to KT; by the VIROGENESIS project that receives funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 634650 to KT. The computational resources and services used in this work were provided by the Hercules Foundation and the Flemish Government – department EWI-FWO Krediet aan Navorsers (Theys, KAN2012 1.5.249.12.) to KT. KT is supported by a postdoctoral grant from FWO. BV is supported by a postdoctoral grant of the FWO (Fonds Wetenschappelijk Onderzoek – Vlaanderen). L’'Oréal Portugal, Comissão Nacional da Unesco and Gilead Génese HIVLatePresenters had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.