Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, Zurich, Switzerland; Institute of Medical Virology, University of Zurich, Zurich, Switzerland
Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, Zurich, Switzerland; Institute of Medical Virology, University of Zurich, Zurich, Switzerland
Claus Kadelka
Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, Zurich, Switzerland; Institute of Medical Virology, University of Zurich, Zurich, Switzerland
Jürg Böni
Institute of Medical Virology, University of Zurich, Zurich, Switzerland
Sabine Yerly
Laboratory of Virology, Geneva University Hospitals, Geneva, Switzerland
Vincent Aubert
Division of Immunology and Allergy, University Hospital Lausanne, Lausanne, Switzerland
Thomas Klimkait
Molecular Virology, Department of Biomedicine - Petersplatz, University of Basel, Basel, Switzerland
Manuel Battegay
Division of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, Basel, Switzerland
Enos Bernasconi
Division of Infectious Diseases, Regional Hospital Lugano, Lugano, Switzerland
Alexandra Calmy
Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
Matthias Cavassini
Service of Infectious Diseases, Department of Medicine, Lausanne University Hospital, Lausanne, Switzerland
Department of Infectious Diseases, Bern University Hospital, University of Bern, Bern, Switzerland
Matthias Hoffmann
Division of Infectious Diseases, Cantonal Hospital St. Gallen, St. Gallen, Switzerland
Huldrych F Günthard
Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, Zurich, Switzerland; Institute of Medical Virology, University of Zurich, Zurich, Switzerland
Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, Zurich, Switzerland; Institute of Medical Virology, University of Zurich, Zurich, Switzerland
Assessing the danger of transition of HIV transmission from a concentrated to a generalized epidemic is of major importance for public health. In this study, we develop a phylogeny-based statistical approach to address this question. As a case study, we use this to investigate the trends and determinants of HIV transmission among Swiss heterosexuals. We extract the corresponding transmission clusters from a phylogenetic tree. To capture the incomplete sampling, the delayed introduction of imported infections to Switzerland, and potential factors associated with basic reproductive number [Formula: see text], we extend the branching process model to infer transmission parameters. Overall, the [Formula: see text] is estimated to be [Formula: see text] ([Formula: see text]-confidence interval [Formula: see text]—[Formula: see text]) and it is decreasing by [Formula: see text] per [Formula: see text] years ([Formula: see text]—[Formula: see text]). Our findings indicate rather diminishing HIV transmission among Swiss heterosexuals far below the epidemic threshold. Generally, our approach allows to assess the danger of self-sustained epidemics from any viral sequence data.
