Specific Aims: Recent studies suggest that very early initiation of ART (prior to seroconversion) does not prevent the establishment of HIV reservoirs, which eventually expand when ART is discontinued (1, 2). Early ART initiation is, however, associated with preservation of CD4+ T cells and lower levels of total HIV DNA and cell-associated RNA (3) as well as preservation of gut Th17 cells, thereby averting a major driver of HIV-related immune activation and limiting the size of the HIV reservoir (4). When, by contrast, ART is initiated in Fiebig III (FIII) or later, many HIV-associated changes have already occurred, including seeding of HIV reservoirs, damage to GI mucosa, and initiation of inflammatory cascades (4). Some if not all of these effects may be related to the development of dysbiosis (a markedly different composition of the gut microbiota that might itself drive continued inflammation). Since ART initiation within weeks of HIV acquisition is not a viable public health strategy, it is important to more completely understand the relative long-term benefits of initiating ART at very early times after infection (FI-II) as opposed to after a short (during FIII-V) or longer delay (at 24 weeks). The effects of alcohol on microbial translocation and pro-inflammatory cytokines are not unlike early changes after HIV infection (5-7); however, alcohol's role in HIV pathogenesis and progression is not well defined. Since the possibility that high-level alcohol use can mitigate the benefits of early ART is emerging as a potentially important public health issue, the investigators will evaluate the impact of time of ART initiation as well as alcohol use on HIV pathogenesis in Peruvian men who have sex with men (MSM), in whom high-level alcohol use is common. They will study outcomes after 1.5 and 3.5 years in MSM diagnosed with acute (Ab-, HIV RNA+) or recent (≤3 months) HIV infection. Three groups based on time of ART initiation will be studied: a) immediate: during FI-II (N~30), b) early: during FIII-V (N~50) or c) delayed: at 24 weeks after diagnosis (N~80).