3. To determine the type-specific prevalence of anal HPV infection in HIV positive Peruvian MSM. Linear array testing will estimate prevalence of 37 HPV types including carcinogenic (16,18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66) and non-carcinogenic types (6, 11, 26, 40, 42, 53, 54, 61, 62, 64, 67, 68, 69, 70, 72, 73, 81, 82, 82var, 83, 84, and 89) as defined at the 2005 meeting of the International Agency for Research on Cancer.