1. Fundació Sida i Societat, Technical Advisor Unit (UAT), Escuintla National Hospital, 5001 Escuintla, Guatemala
2. PhD Programme in Methodology of Biomedical Research and Public Health, Department of Paediatrics, Obstetrics, Gynaecology and Preventive Medicine, Universitat Autònoma de Barcelona, Bellaterra, 08193 Catalonia, Spain
3. Clínica Familiar Luis Ángel García, San Juan de Dios Hospital, Asociación de Salud Integral, 1001 Guatemala City, Guatemala
4. TransLab, Department of Medical Sciences, University of Girona, Girona, 17004 Catalonia, Spain
5. Infectious Diseases Clinic, Roosevelt Hospital, 1011 Guatemala City, Guatemala
6. Juan José Ortega de Coatepeque National Hospital, Coatepeque, 09020 Quetzaltenango, Guatemala
7. Hospital del Instituto Guatemalteco de Seguridad Social (IGSS), 1009 Guatemala City, Guatemala
8. National Programme for Prevention and Control of STI and HIV/AIDS (PNS), 1011 Guatemala City, Guatemala
9. CIBER Epidemiología y Salud Pública (CIBERESP), 28029 Madrid, Spain
10. Center for Epidemiological Studies on HIV/AIDS and STI of Catalonia (CEEISCAT), Institut Català d’Oncologia, Generalitat de Catalunya, Badalona, 08916 Catalonia, Spain