The Association Between Heterosexual anal Intercourse and HIV Acquisition in Three Prospective Cohorts of Women.

The extent to which receptive anal intercourse (RAI) increases the HIV acquisition risk of women compared to receptive vaginal intercourse (RVI) is poorly understood. We evaluated RAI practice over time and its association with HIV incidence during three prospective HIV cohorts of women: RV217, MTN-003 (VOICE), and HVTN 907. At baseline, 16% (RV 217), 18% (VOICE) of women reported RAI in the past 3 months and 27% (HVTN 907) in the past 6 months, with RAI declining during follow-up by around 3-fold. HIV incidence in the three cohorts was positively associated with reporting RAI at baseline, albeit not always significantly. The adjusted hazard rate ratios for potential confounders (aHR) were 1.1 (95% Confidence interval: 0.8-1.5) for VOICE and 3.3 (1.6-6.8) for RV 217, whereas the ratio of cumulative HIV incidence by RAI practice was 1.9 (0.6-6.0) for HVTN 907. For VOICE, the estimated magnitude of association increased slightly when using a time-varying RAI exposure definition (aHR = 1.2; 0.9-1.6), and for women reporting RAI at every follow-up survey (aHR = 2.0 (1.3-3.1)), though not for women reporting higher RAI frequency (> 30% acts being RAI vs. no RAI in the past 3 months; aHR = 0.7 (0.4-1.1)). Findings indicated precise estimation of the RAI/HIV association, following multiple RVI/RAI exposures, is sensitive to RAI exposure definition, which remain imperfectly measured. Information on RAI practices, RAI/RVI frequency, and condom use should be more systematically and precisely recorded and reported in studies looking at sexual behaviors and HIV seroconversions; standardized measures would aid comparability across geographies and over time.

Longitudinal determinants of anal intercourse among women with, and without HIV in the United States.

BACKGROUND: Anal intercourse (AI) is not uncommon among U.S. women and, when condomless, confers a far greater likelihood of HIV transmission than condomless vaginal intercourse. We aim to identify determinants preceding AI, among women with, and women without HIV. METHODS: 3708 women living with (73%), and without HIV (27%) participating in the Women's Interagency HIV Study provided sexual behavior and other data at 6-monthly visits over a median of 9 years (1994-2014). We used generalized estimating equation models to examine sociodemographic, structural and behavioral determinants reported in the visit preceding (1) AI, and (2) condomless AI. RESULTS: AI was reported at least once over follow-up by 31% of women without, and 21% with HIV. AI was commonly condomless; reported at 76% and 51% of visits among women living without HIV, and with HIV, respectively. Women reporting AI were more likely to be younger (continuous variable, adjusted odds ratio (aOR) = 0.97, 95% confidence interval (CI):0.96-0.98), Hispanic (aOR = 1.88, CI:1.47-2.41) or White (aOR = 1.62, CI:1.15-2.30) compared to Black, and have at least high school education (aOR = 1.33, CI:1.08-1.65). AI was more likely following the reporting of either (aOR = 1.35, CI:1.10-1.62), or both (aOR = 1.77, CI:1.13-2.82) physical and sexual violence, excessive drinking (aOR = 1.27, CI:1.05-1.66) or any drug use (aOR = 1.34, CI:1.09-1.66), multiple male partners (aOR = 2.64, CI:2.23-3.11), exchange sex (aOR = 3.45, CI:2.53-4.71), one or more female sex partners (aOR = 1.32, CI:1.01-1.75), condomless vaginal intercourse (aOR = 1.80, CI:1.53-2.09), and high depressive symptoms (aOR = 1.23, CI:1.08-1.39). CONCLUSION: AI disproportionally follows periods of violence victimization, substance use, multiple sex partners and depression. Better prevention messaging and biomedical interventions that reduce acquisition or transmission risk are needed, but when AI occurs in the context of violence against women, as our findings indicate, focusing on gender-based violence reduction and immediate treatment to reduce HIV transmission risk is important.

Patterns and Trajectories of Anal Intercourse Practice Over the Life Course Among US Women at Risk of HIV.

INTRODUCTION: Condomless anal intercourse (AI) confers a far greater likelihood of HIV transmission than condomless vaginal intercourse (VI). However, little is known about AI practice over the life course of women, to what extent AI practice is condom-protected, and whether it is associated with other HIV risk behaviors. We aim to describe longitudinal AI practice among HIV-seronegative women and to identify subgroups with distinct trajectories of AI practice. METHODS: Using data from the Women's Interagency HIV Study, an observational cohort of US women with or at risk for HIV, we described AI practice among HIV-seronegative participants. Group-based trajectory modeling was used to identify distinct AI trajectories. We used multinomial regression to examine associations between baseline characteristics and trajectory group membership. RESULTS: A third of the 1,085 women in our sample reported any AI over follow-up (median follow-up = 14 years). AI decreased more sharply with age compared to VI. Consistent condom use during AI was low: twice the proportion of women never reported using condoms consistently during AI compared to during VI. 5 trajectory groups were identified: AI & VI persistors (N = 75) practiced AI and VI consistently over follow-up (AI & VI desistors (N = 169) tended to practice AI and VI when young only, while VI persistors (N = 549), VI desistors (N = 167), and AI & VI inactives (N = 125) reported varying levels of VI practice, but little AI. AI & VI persistors reported multiple male partners and exchange sex at more visits than other groups. Women who identified as bisexual/lesbian (vs heterosexual), who had ever experienced physical and sexual violence (vs never), and/or who reported above the median number of lifetime male sex partners (vs median or below) had approximately twice the odds of being AI & VI persistors than being VI persistors. CONCLUSIONS: We identified a small subgroup of women who practice AI and report inconsistent condom use along with other risk behaviors throughout the life course; they may therefore particularly benefit from ongoing access to HIV prevention services including pre-exposure prophylaxis. Owen BN, Baggaley RF, Maheu-Giroux M, et al. Patterns and Trajectories of Anal Intercourse Practice Over the Life Course Among US Women at Risk of HIV. J Sex Med 2020;17:1629-1642.

Increases in HIV Incidence Following Receptive Anal Intercourse Among Women: A Systematic Review and Meta-analysis.

Receptive anal intercourse (RAI) carries a greater per-act risk of HIV acquisition than receptive vaginal intercourse (RVI) and may influence HIV epidemics driven by heterosexual sex. This systematic review explores the association between RAI and incident HIV among women, globally. We searched Embase and Medline through September 2018 for longitudinal studies reporting crude (cRR) or adjusted (aRR) relative risks of HIV acquisition by RAI practice among women. Of 27,563 articles identified, 17 eligible studies were included. We pooled independent study estimates using random-effects models. Women reporting RAI were more likely to acquire HIV than women not reporting RAI (pooled cRR = 1.56 95% CI 1.03-2.38, N = 18, I2 = 72%; pooled aRR = 2.23, 1.01-4.92, N = 5, I2 = 70%). In subgroup analyses the association was lower for women in Africa (pooled cRR = 1.16, N = 13, I2 = 21%) than outside Africa (pooled cRR = 4.10, N = 5, I2 = 79%) and for high-risk (pooled aRR = 1.69, N = 4, I2 = 63%) than general-risk women (pooled aRR = 8.50, N = 1). Interview method slightly influenced cRR estimates (p value = 0.04). In leave-one-out sensitivity analyses pooled estimates were generally robust to removing individual study estimates. Main limitations included poor exposure definition, incomplete adjustment for confounders, particularly condom use, and use of non-confidential interview methods. More and better data are needed to explain differences in risk by world region and risk population. Women require better counselling and greater choice in prevention modalities that are effective during RVI and RAI.

What Proportion of Female Sex Workers Practise anal Intercourse and How Frequently? A Systematic Review and Meta-analysis.

HIV is more efficiently acquired during receptive anal intercourse (AI) compared to vaginal intercourse (VI) and may contribute substantially to female sex workers' (FSW) high HIV burden. We aim to determine how common and frequent AI is among FSW globally. We searched PubMed, Embase and PsycINFO for studies reporting the proportion of FSW practising AI (prevalence) and/or the number of AI acts (frequency) worldwide from 01/1980 to 10/2018. We assessed the influence of participant and study characteristics on AI prevalence (e.g. continent, study year and interview method) through sub-group analysis. Of 15,830 identified studies, 131 were included. Nearly all (N = 128) reported AI prevalence and few frequency (N = 13), over various recall periods. Most studies used face-to-face interviews (N = 111). Pooled prevalences varied little by recall period (lifetime: 15.7% 95%CI 12.2-19.3%, N = 30, I2 = 99%; past month: 16.2% 95%CI 10.8-21.6%, N = 18, I2 = 99%). The pooled proportion of FSW reporting < 100% condom use tended to be non-significantly higher during AI compared to during VI (e.g. any unprotected VI: 19.1% 95%CI 1.7-36.4, N = 5 and any unprotected AI: 46.4% 95%CI 9.1-83.6, N = 5 in the past week). Across all study participants, between 2.4 and 15.9% (N = 6) of all intercourse acts (AI and VI) were anal. Neither AI prevalence nor frequency varied substantially by any participant or study characteristics. Although varied, AI among FSW is generally common, inconsistently protected with condoms and practiced sufficiently frequently to contribute substantially to HIV acquisition in this risk group. Interventions to address barriers to condom use are needed.

Prevalence and Frequency of Heterosexual Anal Intercourse Among Young People: A Systematic Review and Meta-analysis.

We aim to assess if heterosexual anal intercourse (AI) is commonly practiced and how frequently it is practiced by young people. We searched PubMed for articles published 1975 to July 2014 reporting data on the proportion of young people (mean age <25) practicing heterosexual AI (AI prevalence) and on number of AI acts (AI frequency). Stratified random-effects meta-analysis and meta-regression were used to produce summary estimates and assess the influence of participant and study characteristics on AI prevalence. Eighty-three and thirteen of the 136 included articles reported data on lifetime AI prevalence and monthly AI frequency, respectively. Estimates were heterogenous. Overall summary estimates of lifetime AI prevalence were 22 % (95 % confidence interval 20-24) among sexually active young people, with no statistically significant differences by gender, continent or age. Prevalence increased significantly with confidentiality of interview method and, among males and in Europe, by survey year. Prevalence did not significantly differ by recall period. An estimated 3-24 % of all reported sex acts were AI. Reported heterosexual AI is common but variable among young people worldwide. To fully understand its impact on STI spread, more and better quality data on frequency of unprotected AI, and trends over time are required.

Assessing the Effectiveness of a Multicomponent Intervention on Hand Hygiene and Well-Being in Primary Health Care Centers and Schools Lacking Functional Water Supply in Protracted Conflict Settings: Protocol for a Cluster Randomized Controlled Trial.

BACKGROUND: Hand hygiene is crucial in health care centers and schools to avoid disease transmission. Currently, little is known about hand hygiene in such facilities in protracted conflict settings. OBJECTIVE: This protocol aims to assess the effectiveness of a multicomponent hand hygiene intervention on handwashing behavior, underlying behavioral factors, and the well-being of health care workers and students. Moreover, we report our methodology and statistical analysis plan transparently. METHODS: This is a cluster randomized controlled trial with 2 parallel arms taking place in 4 countries for 1 year. In Burkina Faso and Mali, we worked in 24 primary health care centers per country, whereas in Nigeria and Palestine, we focused on 26 primary schools per country. Facilities were eligible if they were not connected to a functioning water source but were deemed accessible to the implementation partners. Moreover, health care centers were eligible if they had a maternity ward and ≥5 employees, and schools if they had ≤7000 students studying in grades 5 to 7. We used covariate-constrained randomization to assign intervention facilities that received a hardware, management and monitoring support, and behavior change. Control facilities will receive the same or improved intervention after endline data collection. To evaluate the intervention, at baseline and endline, we used a self-reported survey, structured handwashing observations, and hand-rinse samples. At follow-up, hand-rinse samples were dropped. Starting from the intervention implementation, we collected longitudinal data on hygiene-related health conditions and absenteeism. We also collected qualitative data with focus group discussions and interviews. Data were analyzed descriptively and with random effect regression models with the random effect at a cluster level. The primary outcome for health centers is the handwashing rate, defined as the number of times health care workers performed good handwashing practice with soap or alcohol-based handrub at one of the World Health Organization 5 moments for hand hygiene, divided by the number of moments for hand hygiene that presented themselves during the patient interaction within an hour of observation. For schools, the primary outcome is the number of students who washed their hands before eating. RESULTS: The baseline data collection across all countries lasted from February to June 2023. We collected data from 135 and 174 health care workers in Burkina Faso and Mali, respectively. In Nigeria, we collected data from 1300 students and in Palestine from 1127 students. The endline data collection began in February 2024. CONCLUSIONS: This is one of the first studies investigating hand hygiene in primary health care centers and schools in protracted conflict settings. With our strong study design, we expect to support local policy makers and humanitarian organizations in developing sustainable agendas for hygiene promotion. TRIAL REGISTRATION: ClinicalTrials.gov NCT05946980 (Burkina Faso and Mali); https://www.clinicaltrials.gov/study/NCT05946980 and NCT05964478 (Nigeria and Palestine); https://www.clinicaltrials.gov/study/NCT05964478. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/52959.

Correction: Prevalence and correlates of anal intercourse among female sex workers in eSwatini.

[This corrects the article DOI: 10.1371/journal.pone.0228849.].

Prevalence and correlates of anal intercourse among female sex workers in eSwatini.

INTRODUCTION: As HIV is very effectively acquired during condomless receptive anal intercourse (AI) with serodiscordant and viremic partners, the practice could contribute to the high prevalence among female sex workers (FSW) in eSwatini (formerly known as Swaziland). We aim to estimate the proportion reporting AI (AI prevalence) among Swazi FSW and to identify the correlates of AI practice in order to better inform HIV prevention interventions among this population. METHODS: Using respondent-driven sampling (RDS), 325 Swazi FSW were recruited in 2011. We estimated the prevalence of AI and AI with inconsistent condom use in the past month with any partner type, and inconsistent condom use during AI and vaginal intercourse (VI) by partner type. Univariate and multivariable logistic regression models were used to identify behavioural and structural correlates associated with AI and AI with inconsistent condom use. RESULTS: RDS-adjusted prevalence of AI and AI with inconsistent condom use was high, at 44%[95% confidence interval (95%CI):35-53%]) and 34%[95%CI:26-42%], respectively and did not vary by partner type. HIV prevalence was high in this sample of FSW (70%), but knowledge that AI increases HIV acquisition risk low, with only 10% identifying AI as the riskiest sex act. Those who reported AI were more likely to be better educated (adjusted odds ratio(aOR) = 1.92[95%CI:1.03-3.57]), to have grown up in rural areas (aOR = 1.90[95%CI:1.09-3.32]), have fewer new clients in the past month (aOR = 0.33[95%CI:0.16-0.68]), and for last sex with clients to be condomless (aOR = 2.09[95%CI:1.07-4.08]). Although FSW reporting AI in past month were more likely to have been raped (aOR = 1.95[95%CI:1.05-3.65]) and harassed because of being a sex worker (aOR = 2.09[95%CI:1.16-3.74]), they were also less likely to have ever been blackmailed (aOR = 0.50[95%CI:0.25-0.98]) or been afraid to walk in public places (aOR = 0.46[95%CI:0.25-0.87]). Correlates of AI with inconsistent condom use were similar to those of AI. CONCLUSIONS: AI is commonly practised and condom use is inconsistent among Swazi FSW. Sex act data are needed to determine how frequently AI is practiced. Interventions to address barriers to condom use are needed, as are biomedical interventions that reduce acquisition risk during AI.

Does per-act HIV-1 transmission risk through anal sex vary by gender? An updated systematic review and meta-analysis.

Quantifying HIV-1 transmission risk per-act of anal intercourse (AI) is important for HIV-1 prevention. We updated previous reviews by searching Medline and Embase to 02/2018. We derived pooled estimates of receptive AI (URAI) and insertive AI (UIAI) risk unprotected by condoms using random-effects models. Subgroup analyses were conducted by gender, study design, and whether antiretroviral treatment (ART) had been introduced by the time of the study. Two new relevant studies were identified, one of which met inclusion criteria, adding three new cohorts and increasing number of individuals/partnerships included from 1869 to 14 277. Four studies, all from high-income countries, were included. Pooled HIV-1 risk was higher for URAI (1.25%, 95% CI 0.55%-2.23%, N = 5, I2  = 87%) than UIAI (0.17%, 95 % CI 0.09%-0.26%, N = 3, I2  = 0%). The sole heterosexual URAI estimate (3.38%, 95% CI 1.85%-4.91%), from a study of 72 women published in a peer-reviewed journal, was significantly higher than the men-who-have-sex-with-men (MSM) pooled estimate (0.75%, 95% CI 0.56%-0.98%, N = 4, P < 0.0001) and higher than the only other heterosexual estimate identified (0.4%, 95% CI 0.08%-2.0%, based on 59 women, excluded for being a pre-2013 abstract). Pooled per-act URAI risk varied by study design (retrospective-partner studies: 2.56%, 95% CI 1.20%-4.42%, N = 2 (one MSM, one heterosexual); prospective studies: 0.71%, 95% CI 0.51%-0.93%, N = 3 MSM, P < 0.0001). URAI risk was lower for studies conducted in the ART era (0.75%, 95% CI 0.52%-1.03%) than pre-ART (1.67%, 95% CI 0.44%-3.67%) but not significantly so (P = 0.537). Prevention messages must emphasize that HIV-1 infectiousness through AI remains high, even in the ART era. Further studies, particularly among heterosexual populations and in resource-limited settings, are required to elucidate whether AI risk differs by gender, region and following population-level ART scale-up.

How common and frequent is heterosexual anal intercourse among South Africans? A systematic review and meta-analysis.

BACKGROUND: HIV is transmitted more effectively during anal intercourse (AI) than vaginal intercourse (VI). However, patterns of heterosexual AI practice and its contribution to South Africa's generalized epidemic remain unclear. We aimed to determine how common and frequent heterosexual AI is in South Africa. METHODS: We searched for studies reporting the proportion practising heterosexual AI (prevalence) and/or the number of AI and unprotected AI (UAI) acts (frequency) in South Africa from 1990 to 2015. Stratified random-effects meta-analysis by sub-groups was used to produce pooled estimates and assess the influence of participant and study characteristics on AI prevalence. We also estimated the fraction of all sex acts which were AI or UAI and compared condom use during VI and AI. RESULTS: Of 41 included studies, 31 reported on AI prevalence and 14 on frequency, over various recall periods. AI prevalence was high across different recall periods for sexually active general-risk populations (e.g. lifetime = 18.4% [95%CI:9.4-27.5%], three-month = 20.3% [6.1-34.7%]), but tended to be even higher in higher-risk populations such as STI patients and female sex workers (e.g. lifetime = 23.2% [0.0-47.4%], recall period not stated = 40.1% [36.2-44.0%]). Prevalence was higher in studies using more confidential interview methods. Among general and higher-risk populations, 1.2-40.0% and 0.7-21.0% of all unprotected sex acts were UAI, respectively. AI acts were as likely to be condom protected as vaginal acts. CONCLUSION: Reported heterosexual AI is common but variable among South Africans. Nationally and regionally representative sexual behaviour studies that use standardized recall periods and confidential interview methods, to aid comparison across studies and minimize reporting bias, are needed. Such data could be used to estimate the extent to which AI contributes to South Africa's HIV epidemic.

Heterosexual anal intercourse: a neglected risk factor for HIV?

Heterosexual anal intercourse confers a much greater risk of HIV transmission than vaginal intercourse, yet its contribution to heterosexual HIV epidemics has been under-researched. In this article we review the current state of knowledge of heterosexual anal intercourse practice worldwide and identify the information required to assess its role in HIV transmission within heterosexual populations, including input measures required to inform mathematical models. We then discuss the evidence relating anal intercourse and HIV with sexual violence.