High prevalence of primary antiretroviral resistance among HIV-1-infected adults and children in Bahia, a northeast state of Brazil - Pedroso, Célia; Queiroz, Artur Tl; Alcântara, Luis C; Drexler, Jan F; Diaz, Ricardo S; Weyll, Neide; Brites, Carlos (Journal of acquired immune deficiency syndromes (1999), 2007)