The Study Group consists of the following 62 participating sites in 19 countries (listed with countries, names of participating centers, principal investigators (PI), site coordinators or others centrally involved):

Eastern Europe

Belarus: Belarusian State Medical University, Department of Infectious Disease: I. Karpov (PI), A. Vassilenko (site coordinator); Republican Research and Practical Centre for Pulmonology (Minsk): A. Skrahina (PI), D. Klimuk, A. Skrahin, O. Kondratenko and A. Zalutskaya; Gomel State Medical University (Gomel): V. Bondarenko (PI), V. Mitsura, E. Kozorez, O. Tumash. Gomel Region Centre for Hygiene: O. Suetnov (PI) and D. Paduto;

Estonia: East Viru Central Hospital (Kohtla-Jarve): V. Iljina (PI) and T. Kummik.  

Georgia: Infectious Diseases, AIDS and Clinical Immunology Research Center (Tiblisi): N. Bolokadze (PI), K. Mshvidobadze and N. Lanchava; National Center for Tuberculosis and Lung Diseases of Georgia (Tibilisi): L. Goginashvili, L. Mikiashvili and N. Bablishvili.

Latvia: Infectology Centre of Latvia (Riga): B. Rozentale (PI), I. Zeltina and I. Janushkevich.

Lithuania: Centre for Communicable Diseases and AIDS (Vilnius): I. Caplinskiene (PI), S. Caplinskas, Z. Kancauskiene.

Poland:  Wojewodski Szpital Zakanzy/Medical University of Warsaw (Warszawa): R. Podlasin (PI), A. Wiercinska-Drapalo (PI), M. Thompson and J. Kozlowska; Wojewodski Szpital Specjalistyczny/Medical University Teaching Hospital (Bialystok): A. Grezesczuk (PI). Jozef Strus Multidisciplinary City Hospital (Poznan): M. Bura (PI); Wroclaw University School of Medicine (Wroclaw): B. Knysz (PI) and M. Inglot; Jagiellonian University Medical College (Krakow): A. Garlicki (PI) and J. Loster.

Romania: Dr. Victor Babes Hospital (Bucharest): D. Duiculescu († PI) and S. Tetradov. 
Russia: Botkin Hospital of Infectious Diseases (St. Petersburg): A. Rakhmanova (PI), O. Panteleeva, A. Yakovlev, A. Kozlov, A. Tyukalova and Y. Vlasova; City TB Hospital No. 2 (St. Petersburg): A. Panteleev; Center for Prevention and Control of AIDS (Veliky, Novgorod): T. Trofimov (PI); Medical University Povoljskiy Federal Region.

Ukraine: Crimean Republican AIDS Centre (Simferopol): G. Kyselyova (PI).

Central Northern Europe

Denmark: Rigshospitalet (Cph): N. Obel (PI) and J. Gerstoft; Hvidovre University Hospital: G. Kronborg.

Belgium: CHU Saint-Pierre (Brussels): MC Payen (PI), K. Kabeya and C. Necsoi.

France: Aquitaine Cohort: Cohorte administration: F. Dabis (PI) and A. Tsaranazy (public health resident). Participating Centers and Physicians: Bayonne Hospital; Bordeaux University Hospital: C. Cazanave.   

Switzerland: Swiss HIV Cohort Study (SHCS): Cohorte administration: H. Furrer (PI), M. Sagette (site manager) and M. Rickenbach (head data center). Participating Centers and Physicians: University Hospital Basel:  L. Elzi  and M. Battegay; University Hospital Bern: H. Furrer; Hopital Cantonal Universitaire, Geneve: D. Sculier and A. Calmy; Centre Hospitalaire Universitaire Vaudois, Lausanne: M. Cavassini; Hospital of Lugano:  A. Bruno and E. Bernasconi; Cantonal Hospital St. Gallen: M. Hoffmann and P. Vernazza; University Hospital Zurich: J. Fehr and Prof. R. Weber. 

United Kingdom: Mortimer Market Centre (London): R. Miller (PI) and N. Vora; St. Mary’s Hospital: G. Cooke (PI) and S. Mullaney; North Manchester General Hospital: E. Wilkins (PI) and V. George; Sheffield Teaching Hospitals: P. Collini (PI) and D. Dockrell; King’s College Hospital (London): F. Post (PI), L. Campbell, R. Brum, E. Mabonga and P. Saigal. Queen Elizabeth Hospital: S. Kegg (PI); North Middelsex University Hospital: J. Ainsworth (PI) and A. Waters. Leicester Royal Infirmary: J. Dhar (PI) and K. Ellis.

Southern Europe

Italy: IRCCS - Ospedale L. Spallanzani (Rome): E. Girardi (PI), A Rianda, V. Galati, C. Pinnetti and C. Tommasi; AO San Gerardo (Monza): G. Lapadula (PI); IRCCS AOU San Martino – IST di Genoa (Genova): A. Di Biagio (PI) and A. Parisini; Clinic of Infectious Diseases, University of Bari (Bari): S. Carbonara (PI), G. Angarano  and M. Purgatorio; University of Brescia Spedali Civili: A. Matteelli (PI) and A. Apostoli.

Spain: Barcelona Cohort funded by the Spanish HIV/AIDS Research Network: Hospital Clinic of Barcelona: JM. Miro (PI), C. Manzardo, C. Ligero and J. Gonzalez and Jose A. Martinez-Martinez; Hospital del Mar: F. Sanchez, H. Knobel, M. Salvadó and J.L. Lopez-Colomes; Mutua de Terrassa: X. Martínez-Lacasa and E. Cuchí; Hospital Universitari Vall d’Hebrón: V. Falcó, A. Curran, M.T. Tortola, I. Ocaña and R. Vidal; Hospital Universitari de la Santa Creu i Sant Pau: MA. Sambeat, V. Pomar and P. Coll; Hospital Universitari de Bellvitge: D. Pozamczer, M. Saumoy and F. Alcaide; Agencia de Salud Pública de Barcelona: J. Caylà, A. Moreno, J.P. Millet, A. Orcau, L. Fina, A. Romero, L.L. Roldan. Hospital Universitaria Donostia (San Sebastian): JA. Iribarren (PI) and M. Ibarguren; Hospital Ramon y Cajal (Madrid): S. Moreno (PI) and A. González; Hospital Universitaria ’Gregorio Marañon’’ (Madrid): P. Miralles (PI) and T. Aldámiz-Echevarría.

Latin America: 

Argentina: The CICAL Cohort: Cohorte administration: M. Losso (PI), J. Toibaro and L. Gambardella. Participating Centers and Physicians: Hospital J. M. Ramos Mejía (Buenos Aires): J. Toibaro and L. Moreno Macias; Hospital Paroissien (BA): E. Warley (PI) and S. Tavella; Hospital Piñero (BA): O. Garcia Messina and O. Gear; Hospital Nacional Profesor Alejandro Posadas: H. Laplume;  Hospital Rawson (Cordoba): C. Marson (PI); Hospital San Juan de Dios (La Plata): J. Contarelia and M. Michaan; Hospital General de Agudos Donación F. Santojani: P. Scapellato; Hospital Francisco Javier Muñiz (BA): B. Bartoletti and D. Palmero; Hospital Jujuy: C. Elias.  

Chile: Fundación Arriaran (Santiago): C. Cortes.

México: INNcMZS (México DF): B. Crabtree (PI); Hospital General Regional de Leon- CAPACITS: JL Mosqueda Gomez;  Hospital Civil de Guadalajara: J. A. Villanueva (PI); LA Gonzalez Hernandez and F. Badial