Jessy J Duran Ramirez1,2, Tala Ballouz1,2,3, Huyen Nguyen1,2, Katharina Kusejko1,2, Sandra E Chaudron1,2, Michael Huber2, Hans H Hirsch4,5, Matthieu Perreau6, Alban Ramette7, Sabine Yerly8, Matthias Cavassini9, Marcel Stöckle4, Hansjakob Furrer10, Pietro Vernazza11, Enos Bernasconi12, Huldrych F Günthard1,2, Roger D Kouyos1,2. 1. Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, Zurich, Switzerland. 2. Institute of Medical Virology, University of Zurich, Zurich, Switzerland. 3. Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland. 4. Division of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, University of Basel, Basel, Switzerland. 5. Transplantation and Clinical Virology, Department of Biomedicine, University of Basel, Basel, Switzerland. 6. Division of Immunology and Allergy, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland. 7. Institute for Infectious Diseases, University of Bern, Bern, Switzerland. 8. Laboratory of Virology and Division of Infectious Diseases, Geneva University Hospital, University of Geneva, Geneva, Switzerland. 9. Division of Infectious Diseases, Lausanne University Hospital, Lausanne, Switzerland. 10. Department of Infectious Diseases, Bern University Hospital, University of Bern, Bern, Switzerland. 11. Division of Infectious Diseases, Cantonal Hospital St Gallen, St Gallen, Switzerland. 12. Division of Infectious Diseases, Regional Hospital Lugano, Lugano, Switzerland.
Abstract
BACKGROUND: In Switzerland, HIV-1 transmission among men who have sex with men (MSM) has been dominated by subtype B, whilst non-B subtypes are commonly attributed to infections acquired abroad among heterosexuals. Here, we evaluated the temporal trends of non-B subtypes and the characteristics of molecular transmission clusters (MTCs) among MSM. METHODS: Sociodemographic and clinical data and partial pol sequences were obtained from participants enrolled in the Swiss HIV Cohort Study. For non-B subtypes, maximum likelihood trees were constructed, from which Swiss MTCs were identified and analyzed by transmission group. RESULTS: Non-B subtypes were identified in 8.1% (416/5116) of MSM participants. CRF01_AE was the most prevalent strain (3.5%), followed by subtype A (1.2%), F (1.1%), CRF02_AG (1.1%), C (0.9%), and G (0.3%). Between 1990 and 2019, an increase in the proportion of newly diagnosed individuals (0/123 [0%] to 11/32 [34%]) with non-B subtypes in MSM was found. Across all non-B subtypes, the majority of MSM MTCs were European. Larger MTCs were observed for MSM than heterosexuals. CONCLUSIONS: We found a substantial increase in HIV-1 non-B subtypes among MSM in Switzerland and the occurrence of large MTCs, highlighting the importance of molecular surveillance in guiding public health strategies targeting the HIV-1 epidemic.
BACKGROUND: In Switzerland, HIV-1 transmission among men who have sex with men (MSM) has been dominated by subtype B, whilst non-B subtypes are commonly attributed to infections acquired abroad among heterosexuals. Here, we evaluated the temporal trends of non-B subtypes and the characteristics of molecular transmission clusters (MTCs) among MSM. METHODS: Sociodemographic and clinical data and partial pol sequences were obtained from participants enrolled in the Swiss HIV Cohort Study. For non-B subtypes, maximum likelihood trees were constructed, from which Swiss MTCs were identified and analyzed by transmission group. RESULTS: Non-B subtypes were identified in 8.1% (416/5116) of MSM participants. CRF01_AE was the most prevalent strain (3.5%), followed by subtype A (1.2%), F (1.1%), CRF02_AG (1.1%), C (0.9%), and G (0.3%). Between 1990 and 2019, an increase in the proportion of newly diagnosed individuals (0/123 [0%] to 11/32 [34%]) with non-B subtypes in MSM was found. Across all non-B subtypes, the majority of MSM MTCs were European. Larger MTCs were observed for MSM than heterosexuals. CONCLUSIONS: We found a substantial increase in HIV-1 non-B subtypes among MSM in Switzerland and the occurrence of large MTCs, highlighting the importance of molecular surveillance in guiding public health strategies targeting the HIV-1 epidemic.
Authors: Horacio Gil; Elena Delgado; Sonia Benito; Leonidas Georgalis; Vanessa Montero; Mónica Sánchez; Javier E Cañada-García; Elena García-Bodas; Asunción Díaz; Michael M Thomson Journal: Front Microbiol Date: 2022-03-31 Impact factor: 5.640
Authors: Katharina Kusejko; Nadine Tschumi; Sandra E Chaudron; Huyen Nguyen; Manuel Battegay; Enos Bernasconi; Jürg Böni; Michael Huber; Alexandra Calmy; Matthias Cavassini; Alexander Egle; Katharina Grabmeier-Pfistershammer; Bernhard Haas; Hans Hirsch; Thomas Klimkait; Angela Öllinger; Matthieu Perreau; Alban Ramette; Baharak Babouee Flury; Mario Sarcletti; Alexandra Scherrer; Patrick Schmid; Sabine Yerly; Robert Zangerle; Huldrych F Günthard; Roger D Kouyos Journal: J Acquir Immune Defic Syndr Date: 2022-08-01 Impact factor: 3.771