CROI 2016 Abstract eBook

Abstract Listing

Oral Abstracts

69

Sexually Transmitted Infection Control in the Era of PrEP Sheena McCormack , Univ Coll London, London, UK

Individuals at risk of catching HIV are also at risk of catching other sexually transmitted infections (STIs). Correct and consistent use of condoms virtually eliminates the risk of HIV, but may not prevent the acquisition of bacterial STIs. Syphilis and gonorrhoea have been notifiable diseases for decades in several countries. Trends in infections are explained by many factors including war, migration, access to the pill, as well as new tests and treatments. The emergence of HIV as a fatal infection had a dramatic impact on other STIs which reached an all-time low in gay and other men who have sex with men (MSM) in the late 1980s. This trend in MSM has been completely reversed, driven initially by changes in risk behaviours of HIV positive MSM on effective treatment, but also facilitated by the exponential growth in Social Apps. Conventional control measures (partner notification, epidemiological treatment, outreach in venues) contain transmission to an extent but the shift to group sex in private houses, frequently under the influence of recreational drugs, presents new challenges. What can we anticipate in the era of PrEP? PROUD and IPERGAY enrolled MSM at ‘high risk’ of HIV in England and France respectively. Enrolment criteria were broad – condomless anal sex once in the last 3 months and likely to do so again in the next 3 months (PROUD); 2 or more condomless anal sex partners in the last 6 months (IPERGAY). However, the proportion of PROUD participants that reported rectal bacterial STIs (33%) or syphilis (10%) in the previous year was at least 5-fold higher than all MSM attending clinics in England in 2013 (5% and 2% respectively). So we can anticipate that MSM who are already catching STIs will be more likely than those who are not to present for PrEP, and that they will continue to be at risk of catching STIs whilst on PrEP. It is time to rethink our approach to control of STIs, to make screening, treatment and partner notification as easy as possible, and to find newmethods of population control. One such method is the use of geospatial modelling and analysis to identify the sexual networks that are hotspots for STI transmission. We will need peer-navigators to engage with these networks and bridge the provision of services. As we move into the era of PrEP, it is time to be more creative with the methods we use to control STIs. On our march towards elimination of HIV, we must sort out the STIs on the way. 70 In Chicago, like much of the country, early uptake of PrEP has primarily been seen in middle-aged gay white men. To reach populations most vulnerable to HIV, in particular young gay black men and transgender women of color, more community outreach and creative effort is required. A sampling of other city media/social marketing campaigns will provide the jumping off point for a fast-paced discussion of the twisting, turning road followed by the Chicago PrEP Working Group – highlights of which include the securing of pro bono creative support, raising funds in new and innovative ways, and our community-led concept development, design execution and implementation strategy. The campaign, called “PrEP4Love”, was just launched February 1 throughout Chicago and is positioning PrEP affirmatively in the oft-neglected realm of pleasure and intimacy. Focus populations are young gay Black men, transgender women of color, and cisgender Black heterosexual women. 71 Antiretroviral pre-exposure prophylaxis has huge potential for reducing the rates of new HIV infections in at risk populations. Oral and vaginal antiretroviral formulations have been evaluated in multiple Phase 2B/3 effectiveness trials and there is clear evidence that these products work when used. The converse is also true; antiretrovirals do not work when they are not used. As a consequence, long-acting (LA) injectable and implantable antiretroviral formulations are being developed for the prevention of HIV infection. The two lead products are the non-nucleoside reverse transcriptase inhibitor rilpivirine and the integrase inhibitor cabotegravir. It is hoped that the use of LA antiretroviral PrEP will reduce the burden of product adherence associated with the use of oral and topical products and improve the level of HIV prevention associated with this form of PrEP. Although LA products have clear promise for HIV prevention, there are also challenges to consider. There are concerns about the possibility of idiosyncratic adverse events that would be difficult to manage given the irreversible nature of an LA injection. There are additional concerns about the long half life and extended PK ‘tail’ of these products that might lead to periods of subtherapeutic levels of antiretrovirals; infections acquired during this period might be associated with the development of resistance. The purpose of this presentation is to summarize recent preclinical and clinical research in this area of HIV prevention. 72LB Unreported Cases and Asymptomatic Infection in an Ebola “Hotspot” Eugene T. Richardson 1 ; J. Daniel Kelly 2 ; Mohamed B. Barrie 3 ; AnneliesW. Mesman 3 ; Komba Quiwa 3 ; Sahr Karku 3 ; George Rutherford 2 ; James H. Jones 1 ; Megan Murray 4 ; Paul Farmer 4 1 Stanford Univ, Stanford, CA, USA; 2 Univ of California San Francisco, San Francisco, CA, USA; 3 Partners In Hlth, Freetown, Sierra Leone; 4 Harvard Med School, Boston, MA, USA Background: Evidence for asymptomatic Ebola infection is limited to the extent that, during the 2013-15 outbreak, it was not considered epidemiologically relevant to published epidemic models or projections of intervention effects. We conducted a cross-sectional IgG serosurvey in an Ebola ‘hotspot’ village in Sierra Leone, eight months after reported transmission ceased in that location. The surveyed village had a population of approximately 800 individuals distributed among 110 households. Throughout the entire outbreak, there were 25 cases (18 deaths and 7 survivors) reported by the District Ebola Response Center. Methods: We sampled a total of 227 individuals in 30 of 31 previously quarantined households in the village. We assessed anti–glycoprotein IgG responses to Zaire Ebola virus by means of a commercial ELISA kit (Alpha Diagnostic International [ADI]), according to the manufacturer’s instructions, with plasma diluted at 1:200. Optical density was read at 450 nm (subtracting OD at 630nm to normalize well background) on a ChroMate 4300 microplate reader. We used Welch’s t-test to determine if mean antibody concentrations differed by exposure history. To discriminate between positive and negative IgG responses (cutoff), we used the mean concentration for individuals without direct contact with a confirmed case plus three standard deviations. We then performed a log-binomial regression using this seropositivity cutoff as the dependent variable and gender, age, occupational activity, and schooling as predictor variables. Results: We identified an antibody concentration cutoff of ≥ 1.7 U/mL (roughly equal to 5.1 micrograms per mL). All 7 documented survivors demonstrated positive responses (range 2.1 - 6.3 U/mL). Plasma IgG was positive in an additional 30 of 227 quarantined individuals not known to have Ebola virus disease (Figure 1), 27 of whom denied being symptomatic during the period of active transmission in the village. Only having a higher level of education was significantly associated with seropositivity. Conclusions: This is the first systematic exploration of asymptomatic infection in an Ebola ‘hotspot.’ These data support the hypothesis that the actual number of infections in the 2013-15 outbreak in West Africa is significantly higher than the reported cumulative incidence. The phenomenon of asymptomatic infection has implications for the management of future Ebola outbreaks, as well as for the definition—and treatment—of survivors. PrEP-4-Love: Transmitting Desire Across Chicago James Pickett , AIDS Fndn of Chicago, Chicago, IL, USA The Promise and Challenges of Sustained Delivery of PrEP Ian McGowan , Univ of Pittsburgh Sch of Med, Pittsburgh, PA, USA

Oral Abstracts

27

CROI 2016