Sex, drugs and intersecting risks : HIV among people who belong to more than one key population in the United States

Background The HIV epidemic in the United States (US) is mainly concentrated in so-called ‘key populations’ including men who have sex with men (MSM) and people who inject drugs (PWID). In addition, other groups such as people of low socioeconomic status and people belonging to some ethnic minorities have a higher prevalence of HIV. Globally, people who exchange sex for money or drugs are recognised as another key population with high HIV prevalence, but there is limited recent data from rigorous studies in the United States on HIV prevalence among people who exchange sex. High prevalence among certain groups may be a combination of individual risk behaviours such as condomless sex, drug use and unsafe injection practices, and structural factors such as poverty, violence and residential segregation that can impact HIV risk indirectly. This thesis examines whether, among populations known to be at high risk for HIV, prevalence is higher among those who belong to more than one key population or vulnerable group and for whom several risk factors intersect. Furthermore, it examines sociodemographic factors and sexual and drug-use risk behaviours in these populations and how they may be relevant to HIV acquisition and transmission. Methods Data: I worked with the US National HIV Behavioral Surveillance System (NHBS), which is a surveillance system that collects data from three populations at high risk for HIV in annual rotating cycles: men who have sex with men (MSM), people who inject drugs and heterosexuals at increased risk of HIV (referred to as ‘IDU’ and ‘HET’, respectively). We recruited participants for all three cycles in around 20 large US cities on an annual rotating schedule. For the IDU and HET cycles, we use respondent-driven sampling (RDS), which is a sampling method specifically designed to reach hidden populations and approximate a random sample and where participants recruit each other using coupons. In 2016 I led a pilot data collection focused specifically on women in five cities who exchange sex, also using RDS. During the MSM cycle we recruited participants through venue-based sampling which allows random sampling of venues in a city, time-slots within venues and individual men attending the venue. In all cycles participants take an interviewer-administered survey asking about demographic characteristics, sexual and drug-use risk behaviours and access to services such as frequency of HIV testing and use of health care and preventive services. Participants are also offered a rapid HIV test and receive an incentive for taking the survey and the HIV test. Analysis: For Papers 1 and 2, I looked at women who inject drugs and MSM to examine whether people who exchange sex are more likely to be HIV-infected, including being HIV-positive but unaware of one’s positive status (HIV-positive–unaware), compared with those who do not exchange sex belonging to the same populations. Paper 3 estimates the HIV prevalence among women who exchange sex and compares it with the prevalence among women of low socioeconomic status who do not exchange sex from the same cities three years earlier. In these papers, exchange sex is defined as having had oral, vaginal or anal sex with a male partner in the past 12 months. In Paper 4 I used a subset of the IDU survey data to examine whether MSM who inject drugs (MSM–IDU) are more likely to be HIV infected if they report methamphetamine as their primary drug compared with other drugs. For bivariable and multivariable analyses in Papers 1, 2 and 4 I used generalised estimating equations (GEE), in PROC GENMOD in SAS v. 9.2 or 9.3. The GEE method enables analyses of clustered data where observations in a cluster are thought to be more similar to each other than to other observations. For Paper 3 we used RDSAT to estimate the prevalence of HIV and risk behaviours among women who exchange sex. Results In Paper 1, 10% of women who injected drugs and exchange sex were HIV infected. There was no statistically significant difference in HIV prevalence between those who exchanged sex and those who did not (10.0% vs 7.4%, P = 0.33). However, those who exchanged sex were more likely to be HIV-positive but unaware of their positive status (HIV-positive–unaware) compared with those who did not exchange sex: 5.0% vs 2.6% (P = 0.01). This difference remained significant in multivariable analysis with an adjusted prevalence ratio (aPR) of 1.97 (95% CI 1.31–2.97). In Paper 2, HIV prevalence among MSM who exchanged sex was higher than among MSM who did not (29.1% vs 17.7%, P < 0.001). However, this difference became non-significant in multivariable analysis. MSM who exchanged sex were also more likely to be HIV-positive–unaware than those who did not exchange sex (13.2% vs 5.6%, P ≤ 0.001) and this difference remained in multivariable analysis (aPR 1.34, 95% CI 1.05–1.69). In Paper 3, the prevalence of HIV among women who exchanged sex was 4.9%, approximately three times as high as the prevalence of HIV among women of low socioeconomic status who did not exchange sex (1.6%), and almost nine times as high compared to women in the general population (0.55%). In Paper 4, MSM who primarily injected methamphetamine were significantly more likely to be HIV-positive (29.3%) than MSM who primarily injected other drugs (15.5%, aPR 1.48, 95% CI 1.08–2.03). This association was mediated by sexual risk behaviours, but not drug-use risk behaviours. Among people who exchange sex, and among MSM who inject methamphetamine, sexual and drug-use risk behaviours were common, putting people at risk for HIV acquisition as well as onward transmission. Exchange sex was furthermore common among people living in poverty, homelessness or with other markers of low socioeconomic status. Conclusions The populations studied in this thesis are already known to be at high risk for HIV. This thesis demonstrates that HIV prevalence – in particular the prevalence of being HIV positive but unaware of one’s status – is high among people who belong to more than one key population or vulnerable group. Sexual and drug-use risk behaviours are common. To address the risk for HIV acquisition and onward transmission it is essential to consider a variety of services around prevention, including harm reduction, and testing and linkage to care and treatment. However, narrowly targeted services focusing on a single key population such as people who inject drugs or MSM may not adequately address the needs of those who belong to more than one key population. Additionally, the higher-order structural factors that put individuals and communities at risk for HIV must be addressed

A pilot sentinel surveillance system to monitor treatment and treatment outcomes of chronic hepatitis B and C infections in clinical centres in three European countries, 2019

Hepatitis B; Hepatitis C; SurveillanceHepatitis B; Hepatitis C; VigilanciaHepatitis B; Hepatitis C; VigilànciaBackgroundThe World Health Organization European Action Plan 2020 targets for the elimination of viral hepatitis are that > 75% of eligible individuals with chronic hepatitis B (HBV) or hepatitis C (HCV) are treated, of whom > 90% achieve viral suppression.AimTo report the results from a pilot sentinel surveillance to monitor chronic HBV and HCV treatment uptake and outcomes in 2019.MethodsWe undertook retrospective enhanced data collection on patients with a confirmed chronic HBV or HCV infection presenting at one of seven clinics in three countries (Croatia, Romania and Spain) for the first time between 1 January 2019 and 30 June 2019. Clinical records were reviewed from date of first attendance to 31 December 2019 and data on sociodemographics, clinical history, laboratory results, treatment and treatment outcomes were collected. Treatment eligibility, uptake and case outcome were assessed.ResultsOf 229 individuals with chronic HBV infection, treatment status was reported for 203 (89%). Of the 80 individuals reported as eligible for treatment, 51% (41/80) were treated of whom 89% (33/37) had achieved viral suppression. Of 240 individuals with chronic HCV infection, treatment status was reported for 231 (96%). Of 231 eligible individuals, 77% (179/231) were treated, the majority of whom had received direct acting antivirals (99%, 174/176) and had achieved sustained virological response (98%, 165/169).ConclusionTreatment targets for global elimination were missed for HBV but not for HCV. A wider European implementation of sentinel surveillance with a representative sample of sites could help monitor progress towards achieving hepatitis control targets.The study was supported by the European Centre for Disease Prevention and Control (ECDC) as part of the contract “Sentinel surveillance of hepatitis B and C in the EU/EEA – feasibility, assessment, protocol development and pilot (NP/2019/OCS/10528)”

Willingness to Take, Use of, and Indications for Pre-exposure Prophylaxis Among Men Who Have Sex With Men-20 US Cities, 2014

Pre-exposure prophylaxis (PrEP) is an effective prevention tool for people at substantial risk of acquiring human immunodeficiency virus (HIV). To monitor the current state of PrEP use among men who have sex with men (MSM), we report on willingness to use PrEP and PrEP utilization. To assess whether the MSM subpopulations at highest risk for infection have indications for PrEP according to the 2014 clinical guidelines, we estimated indications for PrEP for MSM by demographics. We analyzed data from the 2014 cycle of the National HIV Behavioral Surveillance (NHBS) system among MSM who tested HIV negative in NHBS and were currently sexually active. Adjusted prevalence ratios and 95% confidence intervals were estimated from log-linked Poisson regression with generalized estimating equations to explore differences in willingness to take PrEP, PrEP use, and indications for PrEP. Whereas over half of MSM said they were willing to take PrEP, only about 4% reported using PrEP. There was no difference in willingness to take PrEP between black and white MSM. PrEP use was higher among white compared with black MSM and among those with greater education and income levels. Young, black MSM were less likely to have indications for PrEP compared with young MSM of other races/ethnicities. Young, black MSM, despite being at high risk of HIV acquisition, may not have indications for PrEP under the current guidelines. Clinicians may need to consider other factors besides risk behaviors such as HIV incidence and prevalence in subgroups of their communities when considering prescribing PrEP

HIV seroprevalence in five key populations in Europe: a systematic literature review, 2009 to 2019

International audienceBackgroundIn Europe, HIV disproportionately affects men who have sex with men (MSM), people who inject drugs (PWID), prisoners, sex workers, and transgender people. Epidemiological data are primarily available from national HIV case surveillance systems that rarely capture information on sex work, gender identity or imprisonment. Surveillance of HIV prevalence in key populations often occurs as independent studies with no established mechanism for collating such information at the European level.AimWe assessed HIV prevalence in MSM, PWID, prisoners, sex workers, and transgender people in the 30 European Union/European Economic Area countries and the United Kingdom.MethodsWe conducted a systematic literature review of peer-reviewed studies published during 2009–19, by searching PubMed, Embase and the Cochrane Library. Data are presented in forest plots by country, as simple prevalence or pooled across multiple studies.ResultsEighty-seven country- and population-specific studies were identified from 23 countries. The highest number of studies, and the largest variation in HIV prevalence, were identified for MSM, ranging from 2.4–29.0% (19 countries) and PWID, from 0.0–59.5% (13 countries). Prevalence ranged from 0.0–15.6% in prisoners (nine countries), 1.1–8.5% in sex workers (five countries) and was 10.9% in transgender people (one country). Individuals belonging to several key population groups had higher prevalence.ConclusionThis review demonstrates that HIV prevalence is highly diverse across population groups and countries. People belonging to multiple key population groups are particularly vulnerable; however, more studies are needed, particularly for sex workers, transgender people and people with multiple risks

A pilot sentinel surveillance system to monitor treatment and treatment outcomes of chronic hepatitis B and C infections in clinical centres in three European countries, 2019

Background The World Health Organization European Action Plan 2020 targets for the elimination of viral hepatitis are that > 75% of eligible individuals with chronic hepatitis B (HBV) or hepatitis C (HCV) are treated, of whom > 90% achieve viral suppression.AimTo report the results from a pilot sentinel surveillance to monitor chronic HBV and HCV treatment uptake and outcomes in 2019. Methods We undertook retrospective enhanced data collection on patients with a confirmed chronic HBV or HCV infection presenting at one of seven clinics in three countries (Croatia, Romania and Spain) for the first time between 1 January 2019 and 30 June 2019. Clinical records were reviewed from date of first attendance to 31 December 2019 and data on sociodemographics, clinical history, laboratory results, treatment and treatment outcomes were collected. Treatment eligibility, uptake and case outcome were assessed. Results Of 229 individuals with chronic HBV infection, treatment status was reported for 203 (89%). Of the 80 individuals reported as eligible for treatment, 51% (41/80) were treated of whom 89% (33/37) had achieved viral suppression. Of 240 individuals with chronic HCV infection, treatment status was reported for 231 (96%). Of 231 eligible individuals, 77% (179/231) were treated, the majority of whom had received direct acting antivirals (99%, 174/176) and had achieved sustained virological response (98%, 165/169). Conclusion Treatment targets for global elimination were missed for HBV but not for HCV. A wider European implementation of sentinel surveillance with a representative sample of sites could help monitor progress towards achieving hepatitis control targets

Modeling in Real Time During the Ebola Response

To aid decision-making during CDC’s response to the 2014–2016 Ebola virus disease (Ebola) epidemic in West Africa, CDC activated a Modeling Task Force to generate estimates on various topics related to the response in West Africa and the risk for importation of cases into the United States. Analysis of eight Ebola response modeling projects conducted during August 2014–July 2015 provided insight into the types of questions addressed by modeling, the impact of the estimates generated, and the difficulties encountered during the modeling. This time frame was selected to cover the three phases of the West African epidemic curve. Questions posed to the Modeling Task Force changed as the epidemic progressed. Initially, the task force was asked to estimate the number of cases that might occur if no interventions were implemented compared with cases that might occur if interventions were implemented; however, at the peak of the epidemic, the focus shifted to estimating resource needs for Ebola treatment units. Then, as the epidemic decelerated, requests for modeling changed to generating estimates of the potential number of sexually transmitted Ebola cases. Modeling to provide information for decision-making during the CDC Ebola response involved limited data, a short turnaround time, and difficulty communicating the modeling process, including assumptions and interpretation of results. Despite these challenges, modeling yielded estimates and projections that public health officials used to make key decisions regarding response strategy and resources required. The impact of modeling during the Ebola response demonstrates the usefulness of modeling in future responses, particularly in the early stages and when data are scarce. Future modeling can be enhanced by planning ahead for data needs and data sharing, and by open communication among modelers, scientists, and others to ensure that modeling and its limitations are more clearly understood