^aIrsiCaixa AIDS Research Institute – HIVACAT, Hospital Germans Trias i Pujol, Badalona, Barcelona, Spain

^bAsociación Civil IMPACTA Salud y Educacion, Lima, Peru

^cUniversitat Autònoma de Barcelona, Barcelona, Spain

^dUniversity of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma

^eDepartment of Global Health, University of Washington, Seattle, Washington, USA

^fInstitució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona

^gUniversitat de Vic, Spain.

Correspondence to Alex Olvera, IrsiCaixa AIDS Research Institute, Hospital Germans Trias i Pujol, Ctra. de Canyet s/n, 08916 Badalona, Barcelona, Spain. Tel: +34 934 656 374; e-mail: [email protected]

Received 31 May, 2014

Revised 1 July, 2014

Accepted 2 July, 2014