A network “sexiogram” differentiates sexual linkages that may or may not have caused new infections.

<p>The individuals represented by the labels A–B and C–D were couples enrolled in the study. The other nodes are sexual partners described by the enrollees. The partnerships were not necessarily concurrent and included all those reported during the 3 months before A's enrollment and those of D, who enrolled 6 months later. Thus, the partnerships spanned a 9-month interval altogether. In some analyses, all partnerships of these HIV-positive individuals known to practice UAI would be counted as potential transmission linkages. This diagram illustrates the preponderance of low-risk partnerships (solid lines) compared with potential transmission linkages (broken lines).</p

General estimating equation models predicting UAI in partnerships.

<p>The HIV-positive status of partner was a strong predictor of sexual practices in partnerships and for individual episodes of intercourse; partners of unknown status were not treated very differently from HIV-negative partners. The analysis also revealed strategic positioning by showing that positive participants were several times more likely to practice insertive rather than receptive UAI in serodiscordant partnerships. ^A HIV-negative partners are the reference group in all cases. ^B Designates the sexual position of the HIV-positive participant.</p

Characteristics of HIV-positive men who have sex with men (MSM) in San Francisco in the Options cohort at the time of first ACASI, 2009–2010.

<p>Characteristics of HIV-positive men who have sex with men (MSM) in San Francisco in the Options cohort at the time of first ACASI, 2009–2010.</p

Estimated mean number of sexual partners per prior 3-month period and 95% confidence intervals [CI] for each sexual behavior variable of interest among MSM in Options/San Francisco, 2009–2010.

∧<p>Number of participants who contribute to each time point varies because this was not a strictly longitudinal cohort study. All participants started contributing data in 2009, and were at various times since diagnosis when they completed their ACASIs.</p>∧∧<p>PDP = potentially discordant partners (HIV-negative or unknown-status partners).</p>*<p>UAI = unprotected anal intercourse.</p>**<p>uIAI = unprotected insertive anal intercourse.</p>***<p>For participants with plasma viral load <500 copies/ml, number of PDP with whom uIAI occurred was set to 0.</p

Mean number of partners of various types per 3 months since HIV diagnosis among HIV-positive MSM in San Francisco, 2009–2010.

<p>An immediate drop in the total number of male partners in the first year of infection was followed by increases in number of partners over the following 3–4 years. The trend was similar for potentially serodiscordand partners (PDPs) although they comprised only 1/3 to 1/2 of total partnerships. However, unprotected anal intercourse (UAI) with PDPs occurred in far fewer partnerships throughout the follow-up period. Partnerships in which the HIV-positive participant was the insertive partner during unprotected anal intercourse (uIAI) accounted for fewer than 10% of all partnerships and in very few of those partnerships did the participant have sufficient plasma viral load (VL >500 copies/ml) to present a significant transmission risk.</p

Temporal trends of HIV cases, San Francisco, 2004–2006.

<p>Temporal trends of HIV cases, San Francisco, 2004–2006.</p

HIV infections stratified by demographic characteristics, risk exposure categories and predictors of risk, San Francisco, 2004–2006.

<p>Denominators:</p>1<p>HIV-Negative.</p>2<p>All HIV Infection.</p>3<p>All Testers.</p>4<p>Long-Term Infection.</p>5<p>Recent Infection.</p>6<p>Acute Infection.</p>7<p>Drug-Resistant Cases.</p

Bivariate and multivariate risk analyses of HIV recent infection, acute infection and drug resistance, MSM testers, San Francisco, 2004–2006.

<p>OR = Odds Ratio.</p><p>AOR = Adjusted Odds Ratio.</p><p>CI = Confidence Intervals.</p><p>P = P-value.</p

Distribution of HIV-1 drug-resistant cases by drug class, San Francisco, 2004–2006.

<p>NRTI = nucleoside reverse transcriptase inhibitors.</p><p>NNRTI = non-nucleoside reverse transcriptase inhibitors.</p><p>PI = protease inhibitors.</p

Scenarios to achieve one third of new infections averted over 10 y.

a<p>Coverage in the uniform distribution strategy is equal in all subgroups (MMSW, MMSM, sex workers, and transwomen at higher risk). The coverage showed in both strategies involving prioritisation (some and high) are given as overall population coverage and, in parentheses, the coverage in each subpopulation (MMSW/MMSM/sex workers/transwomen at higher risk).</p>b<p>Total number of person-years on PrEP over 10 y.</p>c<p>The range represents the variation observed in the estimated costs per PrEP person-year.</p>d<p>Total cost of PrEP intervention over 10 y; the range represents the variation observed in the estimated costs per PrEP person-year.</p