Circumcision and risk of HIV infection in Australian homosexual men

The prevalence and factors of willingness to accept circumcision among MSM in Maanshan City, China

To investigate the prevalence of male circumcision and the willingness to undergo male circumcision and influencing factors among MSM in Maanshan City, we conducted a cross-sectional study from June 2016 to December 2019. Respondent-driven sampling (RDS) was used to recruit participants. Influential factors of willingness to accept circumcision were identified by a multivariable logistic regression model. The multivariable logistic regression model revealed that five variables were independent influential factors for willingness to participate. The factors include that used condoms during last anal intercourse (OR = 1.87, 95% CI:1.03-3.41, P = 0.04), sex with female sex partners (OR = 0.499, 95% CI:0.298-0.860, P = 0.012, level of education (junior college: OR = 0.413, 95% CI:0.200-0.854, P = 0.017; bachelor's degree or higher: OR = 0.442, 95% CI:0.208-0.938, P = 0.033), condom use during oral sex in the last six months (OR = 4.20, 95% CI:1.47-12.0, P = 0.007) and level of knowledge of PrEP (OR = 5.09, 95% CI:1.39-18.7, P = 0.014). Given the willingness of MSM to accept circumcision was low in China, establishing a proper understanding of circumcision is essential if it is to be used as a strategy to prevent HIV infection among MSM. Therefore, publicity and education on the operation should be strengthened to increase the willingness to undergo male circumcision.

Comments by opponents on the British Medical Association's guidance on non-therapeutic male circumcision of children seem one-sided and may undermine public health

The British Medical Association (BMA) guidance on non-therapeutic circumcision (NTMC) of male children is limited to ethical, legal and religious issues. Here we evaluate criticisms of the BMA's guidance by Lempert et al. While their arguments promoting autonomy and consent might be superficially appealing, their claim of high procedural risks and negligible benefits seem one-sided and contrast with high quality evidence of low risk and lifelong benefits. Extensive literature reviews by the American Academy of Pediatrics and the United States Centers for Disease Control and Prevention in developing evidence-based policies, as well as risk-benefit analyses, have found that the medical benefits of infant NTMC greatly exceed the risks, and there is no reduction in sexual function and pleasure. The BMA's failure to consider the medical benefits of early childhood NTMC may partly explain why this prophylactic intervention is discouraged in the United Kingdom. The consequence is higher prevalence of preventable infections, adverse medical conditions, suffering and net costs to the UK's National Health Service for treatment of these. Many of the issues and contradictions in the BMA guidance identified by Lempert et al stem from the BMA's guidance not being sufficiently evidence-based. Indeed, that document called for a review by others of the medical issues surrounding NTMC. While societal factors apply, ultimately, NTMC can only be justified rationally on scientific, evidence-based grounds. Parents are entitled to an accurate presentation of the medical evidence so that they can make an informed decision. Their decision either for or against NTMC should then be respected.

Seronegative MSM at high risk of HIV-1 acquisition show an immune quiescent profile with a normal immune response against common antigens

Human immunodeficiency virus (HIV) infection still represents a major public health problem worldwide, and its vaccine remains elusive. The study of HIV-exposed seronegative individuals (HESN) brings important information about the natural resistance to HIV, allows a better understanding of the infection, and opens doors for new preventive and therapeutic strategies. Among HESN groups, there are some men who have sex with men (MSM) with high-risk sexual behaviors, who represent an adequate cohort for HESN study because of their major HIV exposure without infection. This study aimed to compare the immunological profile of Colombian seronegative MSM with different risk sexual behaviors. This study included 60 MSM at high-risk (n = 16) and low-risk (n = 44) of HIV-1 acquisition. No sex worker nor homozygous delta 32 mutation subjects were included. All participants were negative for anti-HIV-1/2 antibodies and HIV-1 proviral DNA. A higher frequency of sexual partners in the last 3 months before the study participation (median, 30 vs. 2), lifetime sexual partners (median, 1,708 vs. 26), and unprotected anal intercourse (median 12.5 vs. 2) was determined in high-risk MSM than low-risk MSM. High-risk MSM also showed a quiescent profile of T cells and natural killer (NK) cells, with a significantly lower percentage of CD4+CD38+, CD4+HLADR-CD38+, CD4+Ki67+ T cells, and NKG2D+ NK cells (CD3-CD16+CD56+), a significantly higher percentage of CD4+HLADR-CD38-, and a tendency to show a higher percentage of CD8+HLADR+CD38- T cells than the low-risk group. Likewise, they showed higher mRNA levels of Serpin A1 from PBMCs. The results suggest that this MSM cohort could be HESN individuals and their resistance would be explained by a quiescent profile of T cells and NK cells and an increased Serpin A1 expression. Further study on MSM at high risk of exposure to HIV-1 is necessary to better understand the natural resistance to HIV.

Men's Sexual Interest in Feminine Trans Individuals across Cultures

Feminine trans individuals (i.e., individuals who were assigned male at birth but who have a feminine gender presentation and identity) are present in many cultures. In some cultures, these individuals identify as (trans) women. Many of these individuals undergo medical treatments to feminize their bodies (e.g., breast augmentation), but most do not undergo vaginoplasties and therefore have penises. In many non-Western cultures, feminine trans individuals identify as a non-binary gender (i.e., neither man, nor woman). Many of these individuals do not surgically augment their bodies. Across cultures, some men express sexual interest in feminine trans individuals. Are manifestations of sexual interest in feminine trans individuals consistent across Western and non-Western cultural settings? Our review suggests that, across cultures, most of these men are also sexually attracted to cisgender individuals. Many are sexually attracted to cisgender women or to cisgender members of both sexes. A small subset is sexually attracted to cisgender men. Men who are sexually interested in feminine trans individuals commonly report being primarily insertive during anal sex. Additionally, they tend to report that their sexual interest in these individuals is motivated by attraction to femininity or to the combination female- and male-typical characteristics.

Infant Circumcision for Sexually Transmitted Infection Risk Reduction Globally

Population-based studies in high-income countries have failed to find that male circumcision protects against sexually transmitted infections. Using evidence from several sources, we show that male circumcision does protect against HIV during insertive intercourse for men who have sex with men.

Examining Clinical Practice Guidelines for Male Circumcision: A Systematic Review and Critical Appraisal Using AGREE II

OBJECTIVE

To identify and critically appraise available clinical practice guidelines (CPGs) targeting male circumcision using the Appraisal of Guidelines for Research & Evaluation II (AGREE II) instrument.

STUDY DESIGN

A literature search was conducted using electronic databases, CPG databases, and national/international societies providing recommendations to guide clinical decision making for male circumcision. We selected pediatric-focused CPGs related to male circumcision published between January 2010 and December 2020. Non-English CPGs and publications involving narrative reviews, primary research, training manuals, patient and allied health professional guidelines, and technical guides were excluded from our search. Complete CPG documents (including full-text articles, supplemental documents, and associated information) were reviewed. Quality appraisal of CPGs was conducted in accordance with the AGREE II manual.

RESULTS

A total of 163 CPGs were identified, of which 93 were screened and 13 were reviewed. All AGREE II domains demonstrated good to excellent interrater reliability, with intraclass correlation coefficients ranging from 0.82 (95% CI, 0.72-0.89) to 0.93 (95% CI, 0.90-0.95). Most CPGs performed satisfactorily in the clarity of presentation domain and performed poorly in the applicability and editorial independence domains. The top 3 CPGs identified were those of the American Academy of Pediatrics, Centers for Disease Control and Prevention, and Canadian Urological Association. Consistencies among the CPGs were demonstrated across most recommendations.

CONCLUSIONS

Current CPGs are of variable quality, and our findings should be taken into consideration by clinicians and health care professionals when selecting appropriate guidelines for male circumcision.

Circumcision to prevent HIV and other sexually transmitted infections in men who have sex with men: a systematic review and meta-analysis of global data

BACKGROUND

Men who have sex with men (MSM) are disproportionately affected by HIV and other sexually transmitted infections (STIs) worldwide. Previous reviews investigating the role of circumcision in preventing HIV and other STIs among MSM were inconclusive. Many new studies have emerged in the past decade. To inform global prevention strategies for HIV and other STIs among MSM, we reviewed all available evidence on the associations between circumcision and HIV and other STIs among MSM.

METHODS

In this systematic review and meta-analysis, we searched PubMed, Web of Science, BioMed Central, Scopus, ResearchGate, Cochrane Library, Embase, PsycINFO, Google Scholar, and websites of international HIV and STI conferences for studies published before March 8, 2018. Interventional or observational studies containing original quantitative data describing associations between circumcision and incident or prevalent infection of HIV and other STIs among MSM were included. Studies were excluded if MSM could not be distinguished from men who have sex with women only. We calculated pooled odds ratios (ORs) and their 95% CIs using random-effect models. We assessed risk of bias using the Newcastle-Ottawa scale.

FINDINGS

We identified 62 observational studies including 119 248 MSM. Circumcision was associated with 23% reduced odds of HIV infection among MSM overall (OR 0·77, 95% CI 0·67-0·89; number of estimates [k]=45; heterogeneity I²=77%). Circumcision was protective against HIV infection among MSM in countries of low and middle income (0·58, 0·41-0·83; k=23; I²=77%) but not among MSM in high-income countries (0·99, 0·90-1·09; k=20; I²=40%). Circumcision was associated with reduced odds of herpes simplex virus (HSV) infection among MSM overall (0·84, 0·75-0·95; k=5; I²=0%) and penile human papillomavirus (HPV) infection among HIV-infected MSM (0·71, 0·51-0·99; k=3; I²=0%).

INTERPRETATION

We found evidence that circumcision is likely to protect MSM from HIV infection, particularly in countries of low and middle income. Circumcision might also protect MSM from HSV and penile HPV infection. MSM should be included in campaigns promoting circumcision among men in countries of low and middle income. In view of the substantial proportion of MSM in countries of low and middle income who also have sex with women, well designed longitudinal studies differentiating MSM only and bisexual men are needed to clarify the effect of circumcision on male-to-male transmission of HIV and other STIs.

FUNDING

National Natural Science Foundation of China, National Science and Technology Major Project of China, Australian National Health and Medical Research Council Early Career Fellowship, Sanming Project of Medicine in Shenzhen, National Institutes of Health, Mega Projects of National Science Research for the 13th Five-Year Plan, Doris Duke Charitable Foundation.

Critical evaluation of arguments opposing male circumcision: A systematic review

OBJECTIVE

To systematically evaluate evidence against male circumcision (MC).

METHODS

We searched PubMed, Google Scholar, EMBASE and Cochrane databases.

RESULTS

Database searches retrieved 297 publications for inclusion. Bibliographies of these yielded 101 more. After evaluation we found: Claims that MC carries high risk were contradicted by low frequency of adverse events that were virtually all minor and easily treated with complete resolution. Claims that MC causes psychological harm were contradicted by studies finding no such harm. Claims that MC impairs sexual function and pleasure were contradicted by high-quality studies finding no adverse effect. Claims disputing the medical benefits of MC were contradicted by a large body of high-quality evidence indicating protection against a wide range of infections, dermatological conditions, and genital cancers in males and the female sexual partners of men. Risk-benefit analyses reported that benefits exceed risks by 100-200 to 1. To maximize benefits and minimize risks, the evidence supported early infant MC rather than arguments that the procedure should be delayed until males are old enough to decide for themselves. Claims that MC of minors is unethical were contradicted by balanced evaluations of ethical issues supporting the rights of children to be provided with low-risk, high-benefit interventions such as MC for better health. Expert evaluations of case-law supported the legality of MC of minors. Other data demonstrated that early infant MC is cost-saving to health systems.

CONCLUSIONS

Arguments opposing MC are supported mostly by low-quality evidence and opinion, and are contradicted by strong scientific evidence.

Voluntary medical male circumcision and HIV infection among men who have sex with men: Implications from a systematic review

Background:

With the rapidly-increased HIV epidemic among men who have sex with men worldwide, the effectiveness of voluntary medical male circumcision as the tool of HIV prevention still remains undetermined.

Purpose:

In the current study, we conducted a systematic review and meta-analysis to assess the association between voluntary medical male circumcision and HIV risk among men who have sex with men.

Methods and Conclusion:

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline, we conducted a comprehensive literature search through multiple databases. A total of 37 articles/abstracts were included in the analysis. We employed random-effects models and subgroup analyses based upon key study characteristics derived from empirical studies. A total of 117,293 men who have sex with men were included in the meta-analysis, and no randomized control trials have been identified. The odds of being HIV positive were 7% lower among men who have sex with men who were circumcised than among men who have sex with men who were uncircumcised (adjusted odds ratio, 0.93; 95% confidence interval, 0.88–0.99). The evidence for the potential protective effect of voluntary medical male circumcision was stronger among men who have sex with men in Asia and Africa (adjusted odds ratio, 0.62; 95% confidence interval, 0.53–0.73). Our meta-analyses may suggest a protective effect of voluntary medical male circumcision against HIV infection among men who have sex with men, especially in settings like Asia/Africa.

Validation of participant eligibility for pre-exposure prophylaxis: Baseline data from the PRELUDE demonstration project

BACKGROUND

In Australia, pre-exposure prophylaxis (PrEP) is targeted to individuals at high risk for HIV infection. We describe the HIV risk profile and characteristics of PRELUDE participants, and evaluate the population validity of the sample in representing high-risk gay and bisexual men (GBM) eligible for PrEP.

METHODS

PRELUDE is an on-going, open-label, single-arm observational study. Participants were identified in clinics and screened for eligibility using a paper-based risk assessment tool which followed the New South Wales (NSW) PrEP guidelines. Selection was validated using an independent online behavioural survey, completed by study participants upon enrolment. Demographic information was analysed using descriptive statistics, and kappa tests were used to determine agreement between reporting of high-risk practices in the risk assessment and behavioural survey.

RESULTS

During 2014-15, 471 individuals were targeted for enrolment; 341 were assessed for PrEP eligibility and 313 were enrolled. Of these, 303 (97%) identified as GBM. Overall, 85% of GBM met at least one high-risk criterion; 68% reported receptive intercourse with an HIV-positive or unknown status casual male partner, and 37% reported methamphetamine use in the three months preceding enrolment. The remaining 15% were enrolled based on medium-risk behaviours, or at the clinicians' discretion. We found an 82% total agreement between self-reported high-risk behaviour and clinicians' categorisation of GBM as being at high risk for HIV based on PrEP eligibility criteria.

CONCLUSIONS

Behavioural eligibility criteria used by clinicians successfully identified individuals at high risk for HIV infection. This targeted approach ensures that the greatest public health and HIV prevention benefits can be derived in a setting without universal access to PrEP.

CDC's Male Circumcision Recommendations Represent a Key Public Health Measure

Frisch and Earp, opponents of male circumcision, have criticized draft recommendations from the CDC that advocate counseling men and parents of newborn boys in the United States about the benefits and risks of male circumcision. We provide a rebuttal to Frisch and Earp's criticisms and contend that the recommendations are entirely appropriate and merit consideration for policy development.

Early infant male circumcision: Systematic review, risk-benefit analysis, and progress in policy

AIM

To determine whether recent evidence-based United States policies on male circumcision (MC) apply to comparable Anglophone countries, Australia and New Zealand.

METHODS

Articles in 2005 through 2015 were retrieved from PubMed using the keyword "circumcision" together with 36 relevant subtopics. A further PubMed search was performed for articles published in 2016. Searches of the EMBASE and Cochrane databases did not yield additional citable articles. Articles were assessed for quality and those rated 2+ and above according to the Scottish Intercollegiate Grading System were studied further. The most relevant and representative of the topic were included. Bibliographies were examined to retrieve further key references. Randomized controlled trials, recent high quality systematic reviews or meta-analyses (level 1++ or 1+ evidence) were prioritized for inclusion. A risk-benefit analysis of articles rated for quality was performed. For efficiency and reliability, recent randomized controlled trials, meta-analyses, high quality systematic reviews and large well-designed studies were used if available. Internet searches were conducted for other relevant information, including policies and Australian data on claims under Medicare for MC.

RESULTS

Evidence-based policy statements by the American Academy of Pediatrics (AAP) and the Centers for Disease Control and Prevention (CDC) support infant and later age male circumcision (MC) as a desirable public health measure. Our systematic review of relevant literature over the past decade yielded 140 journal articles that met our inclusion criteria. Together, these showed that early infant MC confers immediate and lifelong benefits by protecting against urinary tract infections having potential adverse long-term renal effects, phimosis that causes difficult and painful erections and "ballooning" during urination, inflammatory skin conditions, inferior penile hygiene, candidiasis, various sexually transmissible infections in both sexes, genital ulcers, and penile, prostate and cervical cancer. Our risk-benefit analysis showed that benefits exceeded procedural risks, which are predominantly minor, by up to 200 to 1. We estimated that more than 1 in 2 uncircumcised males will experience an adverse foreskin-related medical condition over their lifetime. Wide-ranging evidence from surveys, physiological measurements, and the anatomical location of penile sensory receptors responsible for sexual sensation strongly and consistently suggested that MC has no detrimental effect on sexual function, sensitivity or pleasure. United States studies showed that early infant MC is cost saving. The evidence supporting early infant MC has further strengthened since the positive AAP and CDC reviews.

CONCLUSION

Affirmative MC policies are needed in Australia and New Zealand. Routine provision of accurate, unbiased education, and access in public hospitals, will maximize health and financial benefits.

High HIV incidence epidemic among men who have sex with men in china: results from a multi-site cross-sectional study

BACKGROUND

Recent upsurge of new HIV infections among men who have sex with men (MSM) is a major concern in China. Paucity of national-level information regarding the burden and predictors of this progressive epidemic of new infections called for a multi-centric, timely and comprehensive investigation.

METHODS

Mixed methods were used to recruit MSM from seven cities in China between 2012 and 2013. Recent and established HIV infections were estimated by Western Blot and BED HIV-1 capture enzyme immunoassay. Syphilis and herpes simplex virus-2 (HSV-2) were also tested.

RESULTS

A total of 4496 eligible MSM were recruited. The majority was aged ≤35 years (77.5 %), migrants (60.3 %), never married (69.8 %), and played receptive role in anal sex (70.5 %). The HIV prevalence was 9.9 %, and 41.9 % were recently infected, with sensitivity/specificity adjusted HIV incidence of 8.9 (95 % CI: 7.6-10.2)/100 Person-Years. The prevalence of history HSV-2 and syphilis were 12.5 % and 8.5 %, respectively. Recent HIV infection was associated with having multiple male partners (aOR = 1.4, 95 % CI 1.1-1.9), recreational drug use (aOR = 2.2, 95 % CI 1.6-3.0), anal bleeding (aOR = 2.1, 95 % CI 1.4-3.0), syphilis infection (aOR = 2.8, 95 % CI 1.9-4.3) and history HSV-2 infection (aOR = 2.3, 95 % CI 1.5-3.3).

CONCLUSION

High rate of recent HIV infection is potentially resulting in progressive deterioration of the overall HIV epidemic among MSM in China. Targeted interventions to address high-risk MSM including those having multiple partners, history of recreational drug use and syphilis or HSV-2 infection seemed to be the need of the hour.

Protocol for an open-label, single-arm trial of HIV pre-exposure prophylaxis (PrEP) among people at high risk of HIV infection: the NSW Demonstration Project PRELUDE

INTRODUCTION

Despite a number of HIV prevention strategies, the number of new HIV infections remains high. In Australia, over three-quarters of new HIV diagnoses are in gay and bisexual men (GBM). Pre-exposure prophylaxis (PrEP) has been shown to be effective at preventing new HIV infections in several randomised trials. The PRELUDE study aims to evaluate the implementation of PrEP in healthcare settings in New South Wales (NSW), Australia, among a sample of high-risk adults.

METHODS AND ANALYSIS

PRELUDE is an ongoing open-label, single-arm demonstration project, conducted in public and private clinics across NSW, Australia. Enrolment began in November 2014. The study is designed for 300 high-risk participants-mainly GBM and heterosexual women. Participants receive daily oral PrEP, composed of emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF), for up to 2.5 years. Quarterly study visits include testing for HIV and sexually transmitted infections (STIs), assessment of ongoing eligibility and side effects, and self-reported adherence. Following each study visit, online behavioural surveys are administered to collect information on medication adherence, risk behaviours and attitudes. Blood samples will be collected in a subset of patients 1, 6 and 12 months after PrEP initiation to measure FTC/TDF concentrations. Analyses using longitudinal regression models will focus on feasibility, adherence, safety, tolerability and effects of PrEP on behaviour. This study will inform PrEP policy and guide the implementation of PrEP in Australia in people at high risk of HIV.

ETHICS AND DISSEMINATION

The study will be conducted in accordance with the Declaration of Helsinki. All patients will provide written informed consent prior to participation in the study. Publications relating to each of the primary end points will be gradually released after 12 months of follow-up is complete.

TRIAL REGISTRATION NUMBER

NCT02206555; Pre-results.

Male circumcision to prevent syphilis in 1855 and HIV in 1986 is supported by the accumulated scientific evidence to 2015: Response to Darby

An article by Darby disparaging male circumcision (MC) for syphilis prevention in Victorian times (1837-1901) and voluntary medical MC programs for HIV prevention in recent times ignores contemporary scientific evidence. It is one-sided and cites outlier studies as well as claims by MC opponents that support the author's thesis, but ignores high quality randomised controlled trials and meta-analyses. While we agree with Darby that risky behaviours contribute to syphilis and HIV epidemics, there is now compelling evidence that MC helps reduce both syphilis and HIV infections. Although some motivations for MC in Victorian times were misguided, others, such as protection against syphilis, penile cancer, phimosis, balanitis and poor hygiene have stood the test of time. In the absence of a cure or effective prophylactic vaccine for HIV, MC should help lower heterosexually acquired HIV, especially when coupled with other interventions such as condoms and behaviour. This should save lives, as well as reducing costs and suffering. In contrast to Darby, our evaluation of the evidence leads us to conclude that MC would likely have helped reduce syphilis in Victorian times and, in the current era, will help lower both syphilis and HIV, so improving global public health.

Male circumcision for protection against HIV infection in sub-Saharan Africa: the evidence in favour justifies the implementation now in progress

This article responds to a recent 'controversy study' in Global Public Health by de Camargo et al. directed at three randomised controlled trials (RCTs) of male circumcision (MC) for HIV prevention. These trials were conducted in three countries in sub-Saharan Africa (SSA) and published in 2005 and 2007. The RCTs confirmed observational data that had accumulated over the preceding two decades showing that MC reduces by 60% the risk of HIV infection in heterosexual men. Based on the RCT results, MC was adopted by global and national HIV policy-makers as an additional intervention for HIV prevention. Voluntary medical MC (VMMC) is now being implemented in 14 SSA countries. Thus referring to MC for HIV prevention as 'debate' and viewing MC through a lens of controversy seems mistaken. In their criticism, de Camargo et al. misrepresent and misinterpret current science supporting MC for HIV prevention, omit previous denunciations of arguments similar to theirs, and ignore evidence from ongoing scientific research. Here we point out the flaws in three areas de Camargo et al. find contentious. In doing so, we direct readers to growing evidence of MC as an efficacious, safe, acceptable, relatively low-cost one-off biomedical intervention for HIV prevention.

A review of the current state of the male circumcision literature

INTRODUCTION

Male circumcision is one of the most commonly performed surgical procedures worldwide and a subject that has been the center of considerable debate. Recently, the American Association of Pediatrics released a statement affirming that the medical benefits of neonatal circumcision outweigh the risks. At present, however, the majority of the literature on circumcision is based on research that is not necessarily applicable to North American populations, as it fails to take into account factors likely to influence the interpretability and applicability of the results.

AIMS

The purpose of this review is to draw attention to the gaps within the circumcision literature that need to be addressed before significant changes to public policy regarding neonatal circumcision are made within North America.

METHODS

A literature review of peer-reviewed journal articles was performed.

MAIN OUTCOME MEASURES

The main outcome measure was the state of circumcision research, especially with regard to new developments in the field, as it applies to North American populations.

RESULTS

This review highlights considerable gaps within the current literature on circumcision. The emphasis is on factors that should be addressed in order to influence research in becoming more applicable to North American populations. Such gaps include a need for rigorous, empirically based methodologies to address questions about circumcision and sexual functioning, penile sensitivity, the effect of circumcision on men's sexual partners, and reasons for circumcision. Additional factors that should be addressed in future research include the effects of age at circumcision (with an emphasis on neonatal circumcision) and the need for objective research outcomes.

CONCLUSION

Further research is needed to inform policy makers, health-care professionals, and stakeholders (parents and individuals invested in this debate) with regard to the decision to perform routine circumcision on male neonates in North America.

Male Circumcision and HIV Transmission; What Do We Know?

Male circumcision (MC) has been shown to be protective against heterosexual HIV transmission and is being explored in some parts of the world as a means of combating the epidemic. The World Health Organization (WHO) recommends that MC be considered as an important component of HIV prevention in high prevalence settings.

We review evidence that demonstrates that the inner foreskin is likely to be the main portal of entry for the HIV virus in males. Whether removal of the inner foreskin accounts for all the protection afforded by circumcision is yet to be established.

The proposed mechanisms of protection range from inherent immunohistological factors of foreskin such as difference in thickness of keratin layer and density of target cells for HIV between inner and outer foreskin to physiological mechanisms that follow male circumcision such as drying of secretions underneath foreskin after sexual intercourse, loss of microbiome that attract target cells to the genital mucosa and lack of priming the genital mucosa with less abundant sexual transmitted infections among circumcised men.

The aim of this review is to give an updated account on the mechanisms proposed so far on the demonstrated 50-70% protection from HIV transmission through heterosexual intercourse, by male circumcision.

Circumcision and HIV infection among men who have sex with men in Britain: the insertive sexual role

The objective was to examine the association between circumcision status and self-reported HIV infection among men who have sex with men (MSM) in Britain who predominantly or exclusively engaged in insertive anal intercourse. In 2007-2008, a convenience sample of MSM living in Britain was recruited through websites, in sexual health clinics, bars, clubs, and other venues. Men completed an online survey which included questions on circumcision status, HIV testing, HIV status, sexual risk behavior, and sexual role for anal sex. The analysis was restricted to 1,521 white British MSM who reported unprotected anal intercourse in the previous 3 months and who said they only or mostly took the insertive role during anal sex. Of these men, 254 (16.7 %) were circumcised. Among men who had had a previous HIV test (n = 1,097), self-reported HIV seropositivity was 8.6 % for circumcised men (17/197) and 8.9 % for uncircumcised men (80/900) (unadjusted odds ratio [OR], 0.97; 95 % confidence interval [95 % CI], 0.56, 1.67). In a multivariable logistic model adjusted for known risk factors for HIV infection, there was no evidence of an association between HIV seropositivity and circumcision status (adjusted OR, 0.79; 95 % CI, 0.43, 1.44), even among the 400 MSM who engaged exclusively in insertive anal sex (adjusted OR, 0.84; 95 % CI, 0.25, 2.81). Our study provides further evidence that circumcision is unlikely to be an effective strategy for HIV prevention among MSM in Britain.

Sexual partner's age as a risk factor for HIV seroconversion in a cohort of HIV-negative homosexual men in Sydney

Increasing partner age may be an important risk factor for HIV infection in homosexual men. About 20 % of 1,427 participants in the Health in Men study in Sydney, Australia, reported that half or more of their partners were much older. Having more partners who were much older was associated with an increased risk of HIV seroconversion (p trend = 0.002), and this remained significant after adjustment for participants' age, number of regular and casual partners, and sexual risk behaviour (p trend = 0.027). Men who reported much older partners were at increased risk of HIV infection, independent of unprotected anal intercourse with sero-nonconcordant partners.

Low frequency of male circumcision and unwillingness to be circumcised among MSM in Buenos Aires, Argentina: association with sexually transmitted infections

Objective

The aims of this study were to investigate the frequency of male circumcision among men who have sex with men (MSM) in Buenos Aires, Argentina; the association between circumcision and sexually transmitted infections (STIs); and, among those uncircumcised, the willingness to be circumcised.

Methods

A cross-sectional study was conducted among 500 MSM recruited through the respondent-driven sampling (RDS) technique. Participants underwent a consent process, responded to a Web-based survey that included questions on demographic information, sexual behaviour, and circumcision and provided biological samples. HIV, hepatitis B virus (HBV), hepatitis C virus (HCV), Treponema pallidum, and human papiloma virus (HPV) diagnoses were performed using standard methodologies. For all analyses, data were weighted based on participants’ network size.

Results

Only 64 (13%) of the 500 MSM in our study reported being circumcised. Among uncircumcised men (n=418), 302 (70.4%) said that they would not be willing to get circumcised even if the procedure could reduce the risk of HIV infection. When considering all participants, circumcision status was not significantly associated with HIV, HBV, HCV, T. pallidum or HPV infections. However, when we restricted the sample to men who do not practice receptive anal intercourse (RAI) and compared circumcised to uncircumcised men, the former (N=33) had no cases of HIV infection, while 34 of 231 (14.8%) uncircumcised men were HIV positive (p=0.020). Regarding HPV, uncircumcised men had a significantly larger number of different HPV types compared with circumcised men (mean 1.83 vs. 1.09, p<0.001) and a higher frequency of high-risk-HPV genotypes (47.6% vs. 12.5%, p=0.012).

Conclusions

Consistent with international evidence, male circumcision appears to have a partial protective effect among MSM. The efficacy of circumcision in reducing risk of HIV infection among MSM appears to be correlated with sexual practices. Given the lack of motivation among MSM with regard to circumcision, proper awareness on the risks and benefits of circumcision needs to be created, if circumcision has to be introduced as a prevention strategy.

Circumcision among men who have sex with men in London, United Kingdom: an unlikely strategy for HIV prevention

OBJECTIVES

To explore attitudes toward circumcision among men who have sex with men (MSM) in London and the feasibility of conducting research into circumcision and HIV prevention in this population.

METHODS

A convenience sample of MSM visiting central London gyms completed a confidential, self-administered questionnaire between May and June 2008. Information was collected on participants' demographic characteristics, self-reported HIV status, sexual behavior, circumcision status, attitudes toward circumcision, and willingness to participate in research on circumcision and HIV prevention.

RESULTS

Of 653 MSM, 29.0% reported that they were circumcised. Overall, HIV prevalence was 23.3%; this did not differ significantly between circumcised and uncircumcised men (18.6% vs. 25.2%, respectively; adjusted odds ratio 0.79, 95% confidence interval: 0.50-1.26). A similar proportion of circumcised and uncircumcised men reported unprotected anal intercourse in the previous 3 months (38.8% vs. 36.7%, adjusted odds ratio 1.06, 95% confidence interval: 0.72-1.55). Uncircumcised men were less likely to think that there were benefits of circumcision than circumcised men (31.2% vs. 65.4, P < 0.001). Only 10.3% of uncircumcised men said that they would be willing to participate in research on circumcision as an HIV prevention strategy.

CONCLUSIONS

Most uncircumcised MSM in this London survey were unwilling to participate in research on circumcision and HIV prevention. Only a minority of uncircumcised men thought that there were benefits of circumcision. It is unlikely that circumcision would be a feasible strategy for HIV prevention among MSM in London.

Popular perceptions of circumcision among Colombian men who have sex with men

Male circumcision has received increased attention for its potential to reduce sexual transmission of HIV. Research on the acceptability of circumcision as a means of HIV prevention among men who have sex with men is limited. Men who have sex with men in Bogotá, Colombia, either participated in a focus group in which they shared information regarding their perceptions of circumcision or completed a survey that assessed circumcision experiences, attitudes, beliefs and willingness. Few participants reported they were circumcised, yet most participants reported knowing something about the procedure. Overall, attitudes towards circumcision were mixed: although circumcision was viewed as safe, it was also viewed as unnatural and cruel to babies. Beliefs that circumcision could improve sexual functioning and protect against STIs and HIV were not widely endorsed by survey participants, although focus-group participants discussed the potential impacts of circumcision on the availability of sexual partners and sexual performance. Some focus-group participants and many survey participants reported a hypothetical willingness to get circumcised if strong evidence of its effectiveness could be provided, barriers removed and recovery time minimised.

Biological basis for the protective effect conferred by male circumcision against HIV infection

Here we provide an up-to-date review of research that explains why uncircumcised men are at higher risk of HIV infection. The inner foreskin is a mucosal epithelium deficient in protective keratin, yet rich in HIV target cells. Soon after sexual exposure to infected mucosal secretions of a HIV-positive partner, infected T-cells from the latter form viral synapses with keratinocytes and transfer HIV to Langerhans cells via dendrites that extend to just under the surface of the inner foreskin. The Langerhans cells with internalized HIV migrate to the basal epidermis and then pass HIV on to T-cells, thus leading to the systemic infection that ensues. Infection is exacerbated in inflammatory states associated with balanoposthitis, the presence of smegma and ulceration - including that caused by infection with herpes simplex virus type 2 and some other sexually transmitted infections (STIs). A high foreskin surface area and tearing of the foreskin or associated frenulum during sexual intercourse also facilitate HIV entry. Thus, by various means, the foreskin is the primary biological weak point that permits HIV infection during heterosexual intercourse. The biological findings could explain why male circumcision protects against HIV infection.

Global epidemiology of HIV infection in men who have sex with men

Epidemics of HIV in men who have sex with men (MSM) continue to expand in most countries. We sought to understand the epidemiological drivers of the global epidemic in MSM and why it continues unabated. We did a comprehensive review of available data for HIV prevalence, incidence, risk factors, and the molecular epidemiology of HIV in MSM from 2007 to 2011, and modelled the dynamics of HIV transmission with an agent-based simulation. Our findings show that the high probability of transmission per act through receptive anal intercourse has a central role in explaining the disproportionate disease burden in MSM. HIV can be transmitted through large MSM networks at great speed. Molecular epidemiological data show substantial clustering of HIV infections in MSM networks, and higher rates of dual-variant and multiple-variant HIV infection in MSM than in heterosexual people in the same populations. Prevention strategies that lower biological transmission and acquisition risks, such as approaches based on antiretrovirals, offer promise for controlling the expanding epidemic in MSM, but their potential effectiveness is limited by structural factors that contribute to low health-seeking behaviours in populations of MSM in many parts of the world.

Review: a critical evaluation of arguments opposing male circumcision for HIV prevention in developed countries

A potential impediment to evidence-based policy development on medical male circumcision (MC) for HIV prevention in all countries worldwide is the uncritical acceptance by some of arguments used by opponents of this procedure. Here we evaluate recent opinion-pieces of 13 individuals opposed to MC. We find that these statements misrepresent good studies, selectively cite references, some containing fallacious information, and draw erroneous conclusions. In marked contrast, the scientific evidence shows MC to be a simple, low-risk procedure with very little or no adverse long-term effect on sexual function, sensitivity, sensation during arousal or overall satisfaction. Unscientific arguments have been recently used to drive ballot measures aimed at banning MC of minors in the USA, eliminate insurance coverage for medical MC for low-income families, and threaten large fines and incarceration for health care providers. Medical MC is a preventative health measure akin to immunisation, given its protective effect against HIV infection, genital cancers and various other conditions. Protection afforded by neonatal MC against a diversity of common medical conditions starts in infancy with urinary tract infections and extends throughout life. Besides protection in adulthood against acquiring HIV, MC also reduces morbidity and mortality from multiple other sexually transmitted infections (STIs) and genital cancers in men and their female sexual partners. It is estimated that over their lifetime one-third of uncircumcised males will suffer at least one foreskin-related medical condition. The scientific evidence indicates that medical MC is safe and effective. Its favourable risk/benefit ratio and cost/benefit support the advantages of medical MC.

A protective effect of circumcision among receptive male sex partners of Indian men who have sex with men

The role of circumcision in the transmission of human immunodeficiency virus (HIV) among men who have sex with men (MSM) in resource restricted regions is poorly understood. This study explored the association of circumcision with HIV seroprevalence, in conjunction with other risk factors such as marriage and sex position, for a population of MSM in India. Participants (n = 387) were recruited from six drop-in centers in a large city in southern India. The overall HIV prevalence in this sample was high, at 18.6%. Bivariate and multivariable analyses revealed a concentration of risk among receptive only, married, and uncircumcised MSM, with HIV prevalence in this group reaching nearly 50%. The adjusted odds of HIV infection amongst circumcised men was less than one fifth that of uncircumcised men [adjusted odds ratio (AOR) 0.17; 95% CI 0.07-0.46; P < 0.001]. Within the group of receptive only MSM, infection was found to be lower among circumcised individuals (AOR, 0.30, 95% CI 0.12-0.76; P < 0.05) in the context of circumcised MSM engaging in more UAI, having a more recent same sex encounter and less lubricant use when compared to uncircumcised receptive men. To further explain these results, future studies should focus on epidemiologic analyses of risk, augmented by social and sexual network analyses of MSM mixing.

Risk factors for HIV-1 seroconversion among Taiwanese men visiting gay saunas who have sex with men

Background

Men having sex with men (MSM) accounts for 33.6% of all reported cases of HIV-1 infection in Taiwan. The aim of this study was to investigate the epidemiology of HIV-1 infection among MSM in gay saunas in Taiwan.

Methods

Patrons of 5 gay saunas were recruited for a weekly volunteer counseling and testing program from 2001 to 2005. Questionnaires were collected for a risk factor analysis. HIV-1 subtypes were determined using DNA sequencing and phylogenetic analyses.

Results

HIV-1 prevalence rates among MSM in gay saunas in 2001 through 2005 were 3.4%, 5.1%, 8.9%, 8.5%, and 8.3%, respectively. In total, 81 of 1, 093 (7.4%) MSM had HIV-1 infection. Fifty-two HIV-1 strains were genotyped, and all of them were subtype B. HIV-seropositive men were significantly younger than the seronegatives. Only 37.1% used condoms every time during sexual intercourse. A multivariate logistic regression analysis showed that the risk factors for HIV-1 were being uncircumcised (odds ratio (OR) = 2.19; 95% confidence interval (CI), 1.08~4.45); having sexual intercourse with at least 2 partners during each sauna visit (≥ 2 vs. ≤ 1, OR = 1.71; 95% CI, 1.02~2.89); and the role played during anal intercourse (versatile vs. an exclusively insertive role, OR = 2.76; 95% CI, 1.42~5.36).

Conclusions

Overall, 7.4% Taiwanese MSM participating in this study had HIV-1 subtype B infection. Uncircumcised, being versatile role during anal intercourse, and having sex with more than one person during each sauna visit were main risk factors for HIV-1 infection.

Human immunodeficiency virus (HIV) immunopathogenesis and vaccine development: a review

The development of a safe, effective and globally affordable HIV vaccine offers the best hope for the future control of the HIV-1 pandemic. Since 1987, scores of candidate HIV-1 vaccines have been developed which elicited varying degrees of protective responses in nonhuman primate models, including DNA vaccines, subunit vaccines, live vectored recombinant vaccines and various prime-boost combinations. Four of these candidate vaccines have been tested for efficacy in human volunteers, but, to the exception of the recent RV144 Phase III trial in Thailand, which elicited a modest but statistically significant level of protection against infection, none has shown efficacy in preventing HIV-1 infection or in controlling virus replication and delaying progression of disease in humans. Protection against infection was observed in the RV144 trial, but intensive research is needed to try to understand the protective immune mechanisms at stake. Building-up on the results of the RV144 trial and deciphering what possibly are the immune correlates of protection are the top research priorities of the moment, which will certainly accelerate the development of an highly effective vaccine that could be used in conjunction with other HIV prevention and treatment strategies. This article reviews the state of the art of HIV vaccine development and discusses the formidable scientific challenges met in this endeavor, in the context of a better understanding of the immunopathogenesis of the disease.

Expected epidemiological impact of the introduction of a partially effective HIV vaccine among men who have sex with men in Australia

A trial of the ALVAC-AIDSVAX HIV vaccine was recently found to be partially effective in preventing HIV transmission among study participants in Thailand. The success of this trial means that vaccination may become a viable intervention for the prevention of HIV infection in the medium-term future. Assuming that the vaccine has similar relative protective effectiveness per exposure event for reducing transmission among men who have sex with men (MSM) in high-income settings we investigated the potential population-level impact of rolling out such a vaccine among MSM in New South Wales, Australia. Using a detailed individual-based transmission model that simulates a population of sexually active MSM it was found that one-off intervention of 60% or 30% coverage of a vaccine with characteristics like the ALVAX-AIDSVAX vaccine would likely reduce the cumulative incidence of HIV by 9.6% and 5.1%, respectively, over a 10-year period. Due to the waning of vaccine efficacy, a booster vaccination could be required to maintain this reduction in incidence over the long term. If the previously vaccinated population is given a booster vaccine, with the same protection conferred as with the initial vaccination, every 5 years or every 2 years then the cumulative incidence over 10 years for 60% coverage could be reduced by 14.4% and 22.8%, respectively. Such a weak vaccine, with boosting, may be a potential intervention strategy for the prevention of HIV infection in MSM in high-income countries if further trials show boosting to be safe, acceptable, and cost-effective. However, the moderately low population-level impact suggests that a public health strategy involving such a vaccine should be supplemented with other biomedical and educational strategies.

Male circumcision for prevention of homosexual acquisition of HIV in men

BACKGROUND

Previous systematic reviews found inconsistent effects of male circumcision on HIV acquisition in men who have sex with men (MSM). However, a number of new studies have become available in the three years since the last systematic review.

OBJECTIVES

To assess the effects of male circumcision for preventing HIV acquisition by men through sex with men.

SEARCH STRATEGY

In June 2010 we electronically searched the Cochrane Central Register of Controlled Trials, PubMed, EMBASE, AIDS Education Global Information System, ClinicalTrials.gov, and WHO International Clinical Trials Registry Platform; hand-searched reference lists of relevant articles; and contacted relevant organisations and experts. We updated the search in March 2011.

SELECTION CRITERIA

We looked for randomised controlled trials (RCTs) and observational studies that assessed the effects of male circumcision on HIV acquisition in MSM.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study eligibility and methodological quality, and extracted data. We expressed study results as odds ratios (OR) with 95% confidence intervals (CI), and conducted random-effects meta-analysis.

MAIN RESULTS

We found no completed RCT and included 21 observational studies with 71,693 participants. The only eligible RCT is currently ongoing among MSM in China. The pooled effect estimate for HIV acquisition was not statistically significant (20 studies; 65,784 participants; OR 0.86, 95% CI 0.70 to 1.06) and showed significant heterogeneity (I²=53%). In a subgroup analysis, the results were statistically significant in studies of men reporting an insertive role (7 studies, 3465 participants; OR 0.27, 95% CI 0.17 to 0.44; I²=0%) but not in studies of men reporting a receptive role (3 studies, 1792 participants; OR 1.20, 95% CI 0.63 to 2.29; I² = 0%). There was no significant association between male circumcision and syphilis (8 studies; 34,999 participants: OR 0.96, 95% CI 0.82 to 1.13; I² = 0%), herpes simplex virus 1 (2 studies, 2740 participants; OR 0.90, 95% CI 0.53 to 1.52; I²=0%), or herpes simplex virus 2 (5 studies;10,285 participants; OR 0.86, 95% CI 0.62 to 1.21; I²=0%). The overall GRADE quality of evidence was low. None of the included studies assessed adverse effects associated with male circumcision.

AUTHORS' CONCLUSIONS

Current evidence suggests that male circumcision may be protective among MSM who practice primarily insertive anal sex, but the role of male circumcision overall in the prevention of HIV and other sexually transmitted infections among MSM remains to be determined. Therefore, there is not enough evidence to recommend male circumcision for HIV prevention among MSM at present. Further research should be of high quality and further explore interaction with the predominant sexual role.

Using population attributable risk to choose HIV prevention strategies in men who have sex with men

Background

In Australia, HIV is concentrated in men who have sex with men (MSM) and rates have increased steadily over the past ten years. Health promotion strategies should ideally be informed by an understanding of both the prevalence of the factors being modified, as well as the size of the risk that they confer. We undertook an analysis of the potential population impact and cost saving that would likely result from modifying key HIV risk factors among men who have sex with men (MSM) in Sydney, Australia.

Methods

Proportional hazard analyses were used to examine the association between sexual behaviours in the last six months and sexually transmissible infections on HIV incidence in a cohort of 1426 HIV-negative MSM who were recruited primarily from community-based sources between 2001 and 2004 and followed to mid-2007. We then estimated the proportion of HIV infections that would be prevented if specific factors were no longer present in the population, using a population attributable risk (PAR) method which controls for confounding among factors. We also calculated the average lifetime healthcare costs incurred by the HIV infections associated with specific factors by estimating costs associated with clinical care and treatment following infection and discounting at 3% (1% and 5% sensitivity) to present value.

Results

Unprotected anal intercourse (UAI) with a known HIV-positive partner was reported by 5% of men, the hazard ratio (HR) was 16.1 (95%CI:6.4-40.5), the PAR was 34% (95%CI:24-44%) and the average lifetime HIV-related healthcare costs attributable to UAI with HIV-positive partners were $AUD102 million (uncertainty range: $93-114 m). UAI with unknown HIV status partners was reported by 25% of men, the HR was 4.4 (95%CI:1.8-11.2), the PAR was 33% (95%CI:26-42%) and the lifetime incurred costs were $AUD99 million. Anal warts prevalence was 4%, the HR was 5.2 (95%CI:2.4-11.2), the PAR was 13% (95%CI:9-19%) and the lifetime incurred costs were $AUD39 million.

Conclusions

Our analysis has found that although UAI with an HIV-positive sexual partner is a relatively low-prevalence behaviour (reported by 5% of men), if this behaviour was not present in the population, the number of infections would be reduced by one third. No other single behaviour or sexually transmissible infections contributes to a greater proportion of infections and HIV-related healthcare costs.

The role of the foreskin in male circumcision: an evidence-based review

HIV sexual transmission via the male genital tract remains poorly defined. Male circumcision was shown to reduce female-to-male transmission in Africa, providing a clue that the foreskin plays a role in the route of transmission. Scientific data in four categories relating to how the foreskin might affect HIV transmission is summarized: (i) surface area, (ii) microbiologic environment, (iii) HIV-1-susceptible cells, and (iv) tissue structure. The relative contribution of each of these areas is yet unknown, and further studies will be crucial in understanding how male circumcision affects HIV transmission in men.

Male circumcision and risk of HIV acquisition among MSM

OBJECTIVES

To assess the association between male circumcision, insertive anal sex practices, and HIV acquisition in a cohort of MSM.

METHODS

Data were from 1824 HSV-2-seropositive, HIV-seronegative MSM, 1362 (75%) from Peru and 462 (25%) from the US, who participated in a randomized placebo-controlled trial of HSV-2 suppression for HIV prevention (HPTN 039). Circumcision status was determined by examination at enrollment. HIV testing was done every 3 months for up to 18 months. Partner-specific sexual behavior for up to the last three partners during the previous 3 months was analyzed.

RESULTS

There was no significant association between male circumcision and HIV acquisition in univariate analysis [relative risk (RR) = 0.84, 95% confidence interval (CI) 0.50-1.42]. In a prespecified multivariate analysis that assumed a linear relationship between the proportion of insertive acts and effect of circumcision on HIV acquisition, the interaction between circumcision and proportion of insertive acts was not significant (P = 0.11). In an exploratory analysis that categorized behavior with recent partners by proportion of insertive acts (<60 or ≥60% insertive acts), circumcision was associated with a nonstatistically significant 69% reduction in the risk of HIV acquisition (RR = 0.31, 95% CI 0.06-1.51) among men who reported at least 60% of insertive acts with recent male partners.

CONCLUSION

Circumcision does not have a significant protective effect against HIV acquisition among MSM from Peru and US, although there may be reduced risk for men who are primarily insertive with their male partners. This association needs to be investigated across diverse cohorts of MSM.

Male circumcision to reduce sexual transmission of HIV

PURPOSE OF REVIEW

Three large trials among African heterosexual men in the last decade have confirmed that male circumcision reduces HIV acquisition. This review summarizes recent data regarding circumcision performed primarily to reduce HIV in high-prevalence settings.

RECENT FINDINGS

Male circumcision more than halved the acquisition of HIV in the trials, and was associated with few adverse events and high levels of satisfaction. An additional trial found no direct reduction in HIV risk for female partners of circumcised men. Evidence for an HIV-protective effect of circumcision in men who have sex with men is weak and inconclusive. Acquisition of HSV-2 and high-risk human papillomavirus are both reduced in circumcised heterosexual men, whereas acquisition of common male urethral pathogens are not. Concerns exist that behavioural disinhibition could offset benefits of this intervention, and it remains to be seen whether the low rate of adverse events and adoption of safer sexual practices observed in the trials will be maintained in circumcision programmes outside trial settings.

SUMMARY

The evidence that circumcision reduces HIV in African heterosexual men is clear. The impedance of political, cultural and logistic factors on expansion of much-needed African circumcision services requires urgent attention.

Per-contact probability of HIV transmission in homosexual men in Sydney in the era of HAART

OBJECTIVE

The objective of this study is to estimate per-contact probability of HIV transmission in homosexual men due to unprotected anal intercourse (UAI) in the era of HAART.

DESIGN

Data were collected from a longitudinal cohort study of community-based HIV-negative homosexual men in Sydney, Australia.

METHODS

A total of 1427 participants were recruited from June 2001 to December 2004. They were followed up with 6-monthly detailed behavioral interviews and annual testing for HIV till June 2007. Data were used in a bootstrapping method, coupled with a statistical analysis that optimized a likelihood function for estimating the per-exposure risks of HIV transmission due to various forms of UAI.

RESULTS

During the study, 53 HIV seroconversion cases were identified. The estimated per-contact probability of HIV transmission for receptive UAI was 1.43% [95% confidence interval (CI) 0.48-2.85] if ejaculation occurred inside the rectum, and it was 0.65% (95% CI 0.15-1.53) if withdrawal prior to ejaculation was involved. The estimated transmission rate for insertive UAI in participants who were circumcised was 0.11% (95% CI 0.02-0.24), and it was 0.62% (95% CI 0.07-1.68) in uncircumcised men. Thus, receptive UAI with ejaculation was found to be approximately twice as risky as receptive UAI with withdrawal or insertive UAI for uncircumcised men and over 10 times as risky as insertive UAI for circumcised men.

CONCLUSION

Despite the fact that a high proportion of HIV-infected men are on antiretroviral treatment and have undetectable viral load, the per-contact probability of HIV transmission due to UAI is similar to estimates reported from developed country settings in the pre-HAART era.

Male circumcision to reduce the risk of HIV and sexually transmitted infections among men who have sex with men

PURPOSE OF REVIEW

The success of male circumcision in reducing HIV acquisition among African heterosexuals has led to renewed interest in this biological intervention for HIV/sexually transmissible infection (STI) prevention in men who have sex with men (MSM). This review summarizes the available data on the association of circumcision and HIV/STI among MSM populations.

RECENT FINDINGS

Results of observational studies indicate that circumcision has limited impact on HIV/STI acquisition among MSM populations overall. Longitudinal data suggest that circumcision may reduce the risk of incident syphilis, but there is little evidence of a protective effect for other STIs. The subgroup of MSM who predominantly practise the insertive role in anal intercourse may be at lower risk of HIV, although the relative inefficiency of HIV acquisition for insertive compared with receptive partners has resulted in imprecise estimates of effect.

SUMMARY

The evidence that circumcision reduces HIV and other STIs among MSM is weak and inconsistent. However, recent studies have found that circumcised MSM who predominantly take the insertive role in anal intercourse may be at a lower risk of HIV infection. Although MSM may be willing to undergo adult circumcision, should it be proven to reduce HIV acquisition risk, there is substantial potential that behavioural disinhibition could offset any benefits achieved by a circumcision intervention.

Cost-effectiveness of newborn circumcision in reducing lifetime HIV risk among U.S. males

BACKGROUND

HIV incidence was substantially lower among circumcised versus uncircumcised heterosexual African men in three clinical trials. Based on those findings, we modeled the potential effect of newborn male circumcision on a U.S. male's lifetime risk of HIV, including associated costs and quality-adjusted life-years saved.

METHODOLOGY/PRINCIPAL FINDINGS

Given published estimates of U.S. males' lifetime HIV risk, we calculated the fraction of lifetime risk attributable to heterosexual behavior from 2005-2006 HIV surveillance data. We assumed 60% efficacy of circumcision in reducing heterosexually-acquired HIV over a lifetime, and varied efficacy in sensitivity analyses. We calculated differences in lifetime HIV risk, expected HIV treatment costs and quality-adjusted life years (QALYs) among circumcised versus uncircumcised males. The main outcome measure was cost per HIV-related QALY saved. Circumcision reduced the lifetime HIV risk among all males by 15.7% in the base case analysis, ranging from 7.9% for white males to 20.9% for black males. Newborn circumcision was a cost-saving HIV prevention intervention for all, black and Hispanic males. The net cost of newborn circumcision per QALY saved was $87,792 for white males. Results were most sensitive to the discount rate, and circumcision efficacy and cost.

CONCLUSIONS/SIGNIFICANCE

Newborn circumcision resulted in lower expected HIV-related treatment costs and a slight increase in QALYs. It reduced the 1.87% lifetime risk of HIV among all males by about 16%. The effect varied substantially by race and ethnicity. Racial and ethnic groups who could benefit the most from circumcision may have least access to it due to insurance coverage and state Medicaid policies, and these financial barriers should be addressed. More data on the long-term protective effect of circumcision on heterosexual males as well as on its efficacy in preventing HIV among MSM would be useful.