Male circumcision and HIV infection in four cities in sub-Saharan Africa

Prevalence of syphilis among adults and adolescents in five sub-Saharan African countries: findings from Population-based HIV Impact Assessment surveys

BACKGROUND

HIV and syphilis are common sexually transmitted infections in sub-Saharan Africa. We aimed to investigate the prevalence and distribution of active syphilis while considering HIV status, demographic characteristics, and behavioural characteristics.

METHODS

The Population-based HIV Impact Assessment surveys used a cross-sectional, two-stage, stratified cluster sample design to collect data in Ethiopia, Tanzania, Uganda, Zambia, and Zimbabwe from 2015 to 2018. Eligible participants were aged 15 years and older and provided demographic information, behavioural information, and blood specimens for HIV and syphilis testing. Active syphilis was defined as the presence of both treponemal and non-treponemal antibodies, measured using an antigen-based rapid test. Multivariable logistic regression models with survey weights were applied. The estimated number of participants with active syphilis in each country was calculated by multiplying the survey-weighted syphilis prevalence by the corresponding participant population size from the latest national census data. The total burden across the five countries was obtained by summing these estimates.

FINDINGS

102 831 participants enrolled in the five surveys (54 583 [57·6%] participants were female, 48 248 [42·4%] participants were male, 9036 [9·9%] participants were HIV positive). Population-based syphilis prevalence was 0·9% (95% CI 0·7-1·1) in Tanzania and Zimbabwe, 2·1% (1·9-2·4) in Uganda, and 3·0% (2·7-3·4) in Zambia. Overall, an estimated 1 027 615 (95% CI 877 243-1 158 246) participants had active syphilis across the five countries (266 383 HIV-positive and 761 232 HIV-negative individuals). Syphilis prevalence was higher among people living with HIV (range from 2·6% [95% CI 1·1-4·0] in Ethiopia to 9·6% [8·1-11·0] in Zambia) than among those without HIV (range from 0·8% [0·7-1·0] in Tanzania to 2·1% [1·8-2·4] in Zimbabwe). The odds of active syphilis were higher among people living with HIV than in those who were HIV negative (adjusted odds ratio [aOR] range from 2·5 [95% CI 1·8-3·4] in Uganda to 5·9 [3·8-9·2] in Zimbabwe), among divorced, separated, or widowed individuals (aOR range from 1·5 [1·1-2·0] in Uganda to 2·7 [1·7-4·3] in Zimbabwe), and among those reporting two or more sexual partners in the previous 12 months (aOR range from 1·1 [CI 0·8-1·5] in Uganda to 1·9 [1·1-3·3] in Zimbabwe).

INTERPRETATION

This study shows the high burden of syphilis in five sub-Saharan African countries, with a correlation between HIV and active syphilis, underscoring the need for integrated sexual health services and targeted diagnosis, prevention, and treatment strategies to address this public health challenge.

FUNDING

The President's Emergency Plan for AIDS Relief through the US Centers for Disease Control and Prevention.

Does Male Circumcision Reduce Women's Risk of Sexually Transmitted Infections, Cervical Cancer, and Associated Conditions?

Background: Male circumcision (MC) is proven to substantially reduce men's risk of a number of sexually transmitted infections (STIs). We conducted a detailed systematic review of the scientific literature to determine the relationship between MC and risk of STIs and associated conditions in women. Methods: Database searches by "circumcision women" and "circumcision female" identified 68 relevant articles for inclusion. Examination of bibliographies of these yielded 14 further publications. Each was rated for quality using a conventional rating system. Results: Evaluation of the data from the studies retrieved showed that MC is associated with a reduced risk in women of being infected by oncogenic human papillomavirus (HPV) genotypes and of contracting cervical cancer. Data from randomized controlled trials and other studies has confirmed that partner MC reduces women's risk not only of oncogenic HPV, but as well Trichomonas vaginalis, bacterial vaginosis and possibly genital ulcer disease. For herpes simplex virus type 2, Chlamydia trachomatis, Treponema pallidum, human immunodeficiency virus and candidiasis, the evidence is mixed. Male partner MC did not reduce risk of gonorrhea, Mycoplasma genitalium, dysuria or vaginal discharge in women. Conclusion: MC reduces risk of oncogenic HPV genotypes, cervical cancer, T. vaginalis, bacterial vaginosis and possibly genital ulcer disease in women. The reduction in risk of these STIs and cervical cancer adds to the data supporting global efforts to deploy MC as a health-promoting and life-saving public health measure and supplements other STI prevention strategies.

Adult gonorrhea, chlamydia and syphilis prevalence, incidence, treatment and syndromic case reporting in South Africa: Estimates using the Spectrum-STI model, 1990-2017

OBJECTIVES

To estimate trends in prevalence and incidence of syphilis, gonorrhea and chlamydia in adult men and women in South Africa.

METHODS

The Spectrum-STI tool estimated trends in prevalence and incidence of active syphilis, gonorrhea and chlamydia, fitting South African prevalence data. Results were used, alongside programmatic surveillance data, to estimate trends in incident gonorrhea cases resistant to first-line treatment, and the reporting gap of symptomatic male gonorrhea and chlamydia cases treated but not reported as cases of urethritis syndrome.

RESULTS

In 2017 adult (15-49 years) the estimated female and male prevalences for syphilis were 0.50% (95% CI: 0.32-0.80%) and 0.97% (0.19-2.28%), for gonorrhea 6.6% (3.8-10.8%) and 3.5% (1.7-6.1%), and for chlamydia 14.7% (9.9-21%) and 6.0% (3.8-10.4%), respectively. Between 1990 and 2017 the estimated prevalence of syphilis declined steadily in women and men, probably in part reflecting improved treatment coverage. For gonorrhea and chlamydia, estimated prevalence and incidence showed no consistent time trend in either women or men. Despite growing annual numbers of gonorrhea cases - reflecting population growth - the estimated number of first line treatment-resistant gonorrhea cases did not increase between 2008 and 2017, owing to changes in first-line antimicrobial treatment regimens for gonorrhea in 2008 and 2014/5. Case reporting completeness among treated male urethritis syndrome episodes was estimated at 10-28% in 2017.

CONCLUSION

South Africa continues to suffer a high STI burden. Improvements in access and quality of maternal, STI and HIV health care services likely contributed to the decline in syphilis prevalence. The lack of any decline in gonorrhea and chlamydia prevalence highlights the need to enhance STI services beyond clinic-based syndromic case management, to reinvigorate primary STI and HIV prevention and, especially for women, to screen for asymptomatic infections.

Geographic variation in sexual behavior can explain geospatial heterogeneity in the severity of the HIV epidemic in Malawi

BACKGROUND

In sub-Saharan Africa, where ~ 25 million individuals are infected with HIV and transmission is predominantly heterosexual, there is substantial geographic variation in the severity of epidemics. This variation has yet to be explained. Here, we propose that it is due to geographic variation in the size of the high-risk group (HRG): the group with a high number of sex partners. We test our hypothesis by conducting a geospatial analysis of data from Malawi, where ~ 13% of women and ~ 8% of men are infected with HIV.

METHODS

We used georeferenced HIV testing and behavioral data from ~ 14,000 participants of a nationally representative population-level survey: the 2010 Malawi Demographic and Health Survey (MDHS). We constructed gender-stratified epidemic surface prevalence (ESP) maps by spatially smoothing and interpolating the HIV testing data. We used the behavioral data to construct gender-stratified risk maps that reveal geographic variation in the size of the HRG. We tested our hypothesis by fitting gender-stratified spatial error regression (SER) models to the MDHS data.

RESULTS

The ESP maps show considerable geographic variation in prevalence: 1-29% (women), 1-20% (men). Risk maps reveal substantial geographic variation in the size of the HRG: 0-40% (women), 16-58% (men). Prevalence and the size of the HRG are highest in urban centers. However, the majority of HIV-infected individuals (~75% of women, ~ 80% of men) live in rural areas, as does most of the HRG (~ 80% of women, ~ 85% of men). We identify a significant (P < 0.001) geospatial relationship linking the size of the HRG with prevalence: the greater the size, the higher the prevalence. SER models show HIV prevalence in women is expected to exceed the national average in districts where > 20% of women are in the HRG. Most importantly, the SER models show that geographic variation in the size of the HRG can explain a substantial proportion (73% for women, 67% for men) of the geographic variation in epidemic severity.

CONCLUSIONS

Taken together, our results provide substantial support for our hypothesis. They provide a potential mechanistic explanation for the geographic variation in the severity of the HIV epidemic in Malawi and, potentially, in other countries in sub-Saharan Africa.

Association between male circumcision and women's biomedical health outcomes: a systematic review

BACKGROUND

Male circumcision reduces men's risk of acquiring HIV and some sexually transmitted infections from heterosexual exposure, and is essential for HIV prevention in sub-Saharan Africa. Studies have also investigated associations between male circumcision and risk of acquisition of HIV and sexually transmitted infections in women. We aimed to review all evidence on associations between male circumcision and women's health outcomes to benefit women's health programmes.

METHODS

In this systematic review we searched for peer-reviewed and grey literature publications reporting associations between male circumcision and women's health outcomes up to April 11, 2016. All biomedical (not psychological or social) outcomes in all study types were included. Searches were not restricted by year of publication, or to sub-Saharan Africa. Publications without primary data and not in English were excluded. We extracted data and assessed evidence on each outcome as high, medium, or low consistency on the basis of agreement between publications; outcomes found in fewer than three publications were indeterminate consistency.

FINDINGS

60 publications were included in our assessment. High-consistency evidence was found for five outcomes, with male circumcision protecting against cervical cancer, cervical dysplasia, herpes simplex virus type 2, chlamydia, and syphilis. Medium-consistency evidence was found for male circumcision protecting against human papillomavirus and low-risk human papillomavirus. Although the evidence shows a protective association with HIV, it was categorised as low consistency, because one trial showed an increased risk to female partners of HIV-infected men resuming sex early after male circumcision. Seven outcomes including HIV had low-consistency evidence and six were indeterminate.

INTERPRETATION

Scale-up of male circumcision in sub-Saharan Africa has public health implications for several outcomes in women. Evidence that female partners are at decreased risk of several diseases is highly consistent. Synergies between male circumcision and women's health programmes should be explored.

FUNDING

US Centers for Disease Control and Prevention and Jhpiego.

Strong associations between national prevalence of various STIs suggests sexual network connectivity is a common underpinning risk factor

Background

If national peak Human Immunodeficiency Virus (HIV) prevalence is positively associated with the prevalence of other sexually transmitted infections (STIs) from before or early on in the HIV epidemics this would suggest common underlying drivers.

Methods

Pearson’s correlations were calculated between the prevalence of seven STIs at a country-level: chlamydia, gonorrhoea, trichomoniasis, syphilis, bacterial vaginosis, herpes simplex virus-2 (HSV-2) and HIV.

Results

The prevalence of all the STIs was highest in the sub-Saharan African region excluding chlamydia. The prevalence of all seven STIs were positively correlated excluding chlamydia. The correlations were strongest for HIV-HSV-2 (r = 0.85, P < 0.0001) and HSV-2-trichomoniasis (r = 0.82, P < 0.0001).

Conclusion

Our results of a generally positive association between the prevalences of a range of STIs suggests that higher prevalences were driven by common underlying determinants. We review different types of evidence which suggest that differential sexual connectivity is a plausible common determinant.

Changes in Male Circumcision Prevalence and Risk Compensation in the Kisumu, Kenya Population, 2008-2013

BACKGROUND

Three randomized controlled trials showed that voluntary medical male circumcision (VMMC) reduces the risk of female-to-male HIV transmission by approximately 60%. However, data from communities where VMMC programs have been implemented are needed to assess changes in circumcision prevalence and whether men and women compensate for perceived reductions in risk by increasing their HIV risk behaviors.

METHODS

Scale-up of free VMMC began in Kisumu, Kenya in 2008. Between 2009 and 2013, a sequence of 3 unlinked cross-sectional surveys were conducted. All individuals 15-49 years of age residing in randomly selected households were interviewed and offered HIV testing. Male circumcision status was confirmed by examination. Design-adjusted bivariate comparisons and multivariable analyses were used for statistical inference.

RESULTS

The prevalence of male circumcision increased from 32% (95% CI: 26% to 38%) in 2009 to 60% (95% CI: 56% to 63%) in 2013. The adjusted prevalence ratio of HIV and genital ulcer disease in circumcised compared with uncircumcised men was 0.48 (95% CI: 0.36 to 0.66) and 0.51 (95% CI: 0.37 to 0.69), respectively. There was no association between circumcision status and sexual behaviors, HIV knowledge, or indicators of risk perception.

CONCLUSIONS

The conditions necessary for the VMMC program to have a significant public health impact are present in Kisumu, Kenya. Between 2009 and 2013, circumcision prevalence increased from 30% to 60%; HIV prevalence in circumcised men was half that of uncircumcised men, and there was no or minimal sexual risk compensation.

Male Circumcision and the Epidemic Emergence of HIV-2 in West Africa

BACKGROUND

Epidemic HIV-2 (groups A and B) emerged in humans circa 1930-40. Its closest ancestors are SIVsmm infecting sooty mangabeys from southwestern Côte d'Ivoire. The earliest large-scale serological surveys of HIV-2 in West Africa (1985-91) show a patchy spread. Côte d'Ivoire and Guinea-Bissau had the highest prevalence rates by then, and phylogeographical analysis suggests they were the earliest epicenters. Wars and parenteral transmission have been hypothesized to have promoted HIV-2 spread. Male circumcision (MC) is known to correlate negatively with HIV-1 prevalence in Africa, but studies examining this issue for HIV-2 are lacking.

METHODS

We reviewed published HIV-2 serosurveys for 30 cities of all West African countries and obtained credible estimates of real prevalence through Bayesian estimation. We estimated past MC rates of 218 West African ethnic groups, based on ethnographic literature and fieldwork. We collected demographic tables specifying the ethnic partition in cities. Uncertainty was incorporated by defining plausible ranges of parameters (e.g. timing of introduction, proportion circumcised). We generated 1,000 sets of past MC rates per city using Latin Hypercube Sampling with different parameter combinations, and explored the correlation between HIV-2 prevalence and estimated MC rate (both logit-transformed) in the 1,000 replicates.

RESULTS AND CONCLUSIONS

Our survey reveals that, in the early 20th century, MC was far less common and geographically more variable than nowadays. HIV-2 prevalence in 1985-91 and MC rates in 1950 were negatively correlated (Spearman rho = -0.546, IQR: -0.553--0.546, p≤0.0021). Guinea-Bissau and Côte d'Ivoire cities had markedly lower MC rates. In addition, MC was uncommon in rural southwestern Côte d'Ivoire in 1930.The differential HIV-2 spread in West Africa correlates with different historical MC rates. We suggest HIV-2 only formed early substantial foci in cities with substantial uncircumcised populations. Lack of MC in rural areas exposed to bushmeat may have had a role in successful HIV-2 emergence.

Strong Country Level Correlation between Syphilis and HSV-2 Prevalence

Background. Syphilis is curable but Herpes Simplex Virus-2 (HSV-2) is not. As a result, the prevalence of syphilis but not HSV-2 may be influenced by the efficacy of national STI screening and treatment capacity. If the prevalence of syphilis and HSV-2 is found to be correlated, then this makes it more likely that something other than differential STI treatment is responsible for variations in the prevalence of both HSV-2 and syphilis. Methods. Simple linear regression was used to evaluate the relationship between national antenatal syphilis prevalence and HSV-2 prevalence in women in two time periods: 1990–1999 and 2008. Adjustments were performed for the laboratory syphilis testing algorithm used and the prevalence of circumcision. Results. The prevalence of syphilis was positively correlated with that of HSV-2 for both time periods (adjusted correlations, 20–24-year-olds: 1990–99: R² = 0.54, P < 0.001; 2008: R² = 0.41, P < 0.001 and 40–44-year-olds: 1990–99: R² = 0.42, P < 0.001; 2008: R² = 0.49, P < 0.001). Conclusion. The prevalence of syphilis and HSV-2 is positively correlated. This could be due to a common set of risk factors underpinning both STIs.

Estimation of country-specific and global prevalence of male circumcision

BACKGROUND

Male circumcision (MC) status and genital infection risk are interlinked and MC is now part of HIV prevention programs worldwide. Current MC prevalence is not known for all countries globally. Our aim was to provide estimates for country-specific and global MC prevalence.

METHODS

MC prevalence data were obtained by searches in PubMed, Demographic and Health Surveys, AIDS Indicator Surveys, and Behavioural Surveillance Surveys. Male age was ≥15 years in most surveys. Where no data were available, the population proportion whose religious faith or culture requires MC was used. The total number of circumcised males in each country and territory was calculated using figures for total males from (i) 2015 US Central Intelligence Agency (CIA) data for sex ratio and total population in all 237 countries and territories globally and (ii) 2015 United Nations (UN) figures for males aged 15-64 years.

RESULTS

The estimated percentage of circumcised males in each country and territory varies considerably. Based on (i) and (ii) above, global MC prevalence was 38.7 % (95 % confidence interval [CI]: 33.4, 43.9) and 36.7 % (95 % CI: 31.4, 42.0). Approximately half of circumcisions were for religious and cultural reasons. For countries lacking data we assumed 99.9 % of Muslims and Jews were circumcised. If actual prevalence in religious groups was lower, then MC prevalence in those countries would be lower. On the other hand, we assumed a minimum prevalence of 0.1 % related to MC for medical reasons. This may be too low, thereby underestimating MC prevalence in some countries.

CONCLUSIONS

The present study provides the most accurate estimate to date of MC prevalence in each country and territory in the world. We estimate that 37-39 % of men globally are circumcised. Considering the health benefits of MC, these data may help guide efforts aimed at the use of voluntary, safe medical MC in disease prevention programs in various countries.

Poverty, food insufficiency and HIV infection and sexual behaviour among young rural Zimbabwean women

Background

Despite a recent decline, Zimbabwe still has the fifth highest adult HIV prevalence in the world at 14.7%; 56% of the population are currently living in extreme poverty.

Design

Cross-sectional population-based survey of 18–22 year olds, conducted in 30 communities in south-eastern Zimbabwe in 2007.

Objective

To examine whether the risk of HIV infection among young rural Zimbabwean women is associated with socio-economic position and whether different socio-economic domains, including food sufficiency, might be associated with HIV risk in different ways.

Methods

Eligible participants completed a structured questionnaire and provided a finger-prick blood sample tested for antibodies to HIV and HSV-2. The relationship between poverty and HIV was explored for three socio-economic domains: ability to afford essential items; asset wealth; food sufficiency. Analyses were performed to examine whether these domains were associated with HIV infection or risk factors for infection among young women, and to explore which factors might mediate the relationship between poverty and HIV.

Results

2593 eligible females participated in the survey and were included in the analyses. Overall HIV prevalence among these young females was 7.7% (95% CI: 6.7–8.7); HSV-2 prevalence was 11.2% (95% CI: 9.9–12.4). Lower socio-economic position was associated with lower educational attainment, earlier marriage, increased risk of depression and anxiety disorders and increased reporting of higher risk sexual behaviours such as earlier sexual debut, more and older sexual partners and transactional sex. Young women reporting insufficient food were at increased risk of HIV infection and HSV-2.

Conclusions

This study provides evidence from Zimbabwe that among young poor women, economic need and food insufficiency are associated with the adoption of unsafe behaviours. Targeted structural interventions that aim to tackle social and economic constraints including insufficient food should be developed and evaluated alongside behaviour and biomedical interventions, as a component of HIV prevention programming and policy.

Migration intensity has no effect on peak HIV prevalence: an ecological study

Background

Correctly identifying the determinants of generalized HIV epidemics is crucial to bringing down ongoing high HIV incidence in these countries. High rates of migration are believed to be an important determinant of HIV prevalence. This study has two aims. Firstly, it evaluates the ecological association between levels of internal and international migration and national peak HIV prevalence using thirteen variables from a variety of sources to capture various aspects of internal and international migration intensity. Secondly, it examines the relationship between circular migration and HIV at an individual and population-level in South Africa.

Methods

Linear regression was used to analyze the association between the various measures of migration intensity and peak national HIV prevalence for 141 countries and HIV prevalence by province and ethnic group in South Africa.

Results

No evidence of a positive ecological association between national migration intensity and HIV prevalence was found. This remained the case when the analyses were limited to the countries of sub-Saharan Africa. On the whole, countries with generalized HIV epidemics had lower rates of internal and external migration. Likewise, no association was found between migration and HIV positivity at an individual or group-level in South Africa.

Conclusion

These results do not support the thesis that migration measured at the country level plays a significant role in determining peak HIV prevalence.

Strong association between in-migration and HIV prevalence in urban sub-Saharan Africa

BACKGROUND

Enormous variation exists in HIV prevalence between countries in sub-Saharan Africa. The contribution of migration to the spread of HIV has long been recognized, but its effect at the population level has never been assessed. In this ecological analysis, we explore how much variation in HIV prevalence in urban sub-Saharan Africa is explained by in-migration.

METHODS

We performed a linear regression to analyze the association between the proportion of recent in-migrants and HIV prevalence for men and women in urban areas, using 60 data points from 28 sub-Saharan African countries between 1987 and 2005.

RESULTS

We found a strong association between recent in-migration and HIV prevalence for women (Pearson R = 57%, P < 0.001) and men (R = 24%, P = 0.016), taking the earliest data point for each country. For women, the association was also strong within east/southern Africa (R = 50%, P = 0.003). For both genders, the association was strongest between 1985 and 1994, slightly weaker between 1995 and 1999, and nonexistent as from 2000. The overall association for both men and women was not confounded by the developmental indicators GNI per capita, income inequalities, or adult literacy.

CONCLUSIONS

Migration explains much of the variation in HIV spread in urban areas of sub-Saharan Africa, especially before the year 2000, after which HIV prevalences started to level off in many countries. Our findings suggest that migration is an important factor in the spread of HIV, especially in rapidly increasing epidemics. This may be of relevance to the current HIV epidemics in China and India.

Translation of biomedical prevention strategies for HIV: prospects and pitfalls

Early achievements in biomedical approaches for HIV prevention included physical barriers (condoms), clean injection equipment (both for medical use and for injection drug users), blood and blood product safety, and prevention of mother-to-child transmission. In recent years, antiretroviral drugs to reduce the risk of transmission (when the infected person takes the medicines; treatment as prevention) or reduce the risk of acquisition (when the seronegative person takes them; preexposure prophylaxis) have proven to be efficacious. Circumcision of men has also been a major tool relevant for higher prevalence regions such as sub-Saharan Africa. Well-established prevention strategies in the control of sexually transmitted diseases and tuberculosis are highly relevant for HIV (ie, screening, linkage to care, early treatment, and contact tracing). Unfortunately, only slow progress is being made in some available HIV-prevention strategies such as family planning for HIV-infected women who do not want more children and prevention of mother-to-child HIV transmission. Current studies seek to integrate strategies into approaches that combine biomedical, behavioral, and structural methods to achieve prevention synergies. This review identifies the major biomedical approaches demonstrated to be efficacious that are now available. We also highlight the need for behavioral risk reduction and adherence as essential components of any biomedical approach.

Fifteen million people on antiretroviral treatment by 2015: treatment as prevention

PURPOSE OF REVIEW

The declaration of the United Nations High Level meeting on AIDS in June 2011 includes 10 concrete targets, including to ensure that there are 15 million people living with human immunodeficiency virus (HIV) on antiretroviral treatment (ART) by 2015. This review examines the potential, opportunities and challenges of treatment as prevention of HIV and tuberculosis (TB) in reaching this target.

RECENT FINDINGS

Although around 8 million people are on treatment, everyone living with HIV will eventually need ART to stay alive. As many as 24  million people living with HIV today are not on treatment, the majority not even being aware of their HIV infection. Expansion of a comprehensive prevention strategy including providing ART to 15 million or more people would significantly reduce HIV and TB morbidity, mortality and transmission. The challenges include ensuring human rights protections, steady drug supply, early diagnosis and linkage to care, task shifting, adherence, retention, and monitoring and evaluation. Expansion could also lead to the control and possible elimination of HIV in many places.

SUMMARY

Achieving an 'AIDS-free generation' whereby deaths related to HIV are drastically reduced, people living with HIV are AIDS-free on ART, and HIV transmission is decreased, is both scientifically sound and practically feasible. The global community could reach 15 million people on ART by 2015 while expanding our vision and efforts to include diagnosis and treatment for all the 32  million people living with HIV in the future.

Sexually transmitted infections and male circumcision: a systematic review and meta-analysis

The claim that circumcision reduces the risk of sexually transmitted infections has been repeated so frequently that many believe it is true. A systematic review and meta-analyses were performed on studies of genital discharge syndrome versus genital ulcerative disease, genital discharge syndrome, nonspecific urethritis, gonorrhea, chlamydia, genital ulcerative disease, chancroid, syphilis, herpes simplex virus, human papillomavirus, and contracting a sexually transmitted infection of any type. Chlamydia, gonorrhea, genital herpes, and human papillomavirus are not significantly impacted by circumcision. Syphilis showed mixed results with studies of prevalence suggesting intact men were at great risk and studies of incidence suggesting the opposite. Intact men appear to be of greater risk for genital ulcerative disease while at lower risk for genital discharge syndrome, nonspecific urethritis, genital warts, and the overall risk of any sexually transmitted infection. In studies of general populations, there is no clear or consistent positive impact of circumcision on the risk of individual sexually transmitted infections. Consequently, the prevention of sexually transmitted infections cannot rationally be interpreted as a benefit of circumcision, and any policy of circumcision for the general population to prevent sexually transmitted infections is not supported by the evidence in the medical literature.

Baseline findings of an HIV incidence cohort study to prepare for future HIV prevention clinical trials in Kisumu, Kenya

Introduction

In an analysis of baseline findings of an HIV incidence cohort study, an assessment was made of HIV prevalence among persons presenting for enrollment and any differences in demographic characteristics between persons not enrolled compared to those enrolled. We also described and compared HIV risk behaviors in males and females enrolled in the study.

Methodology

A computer-assisted survey was administered to collect baseline demographic and HIV risk data from 1,277 men and women aged 18–34 years. Testing for HIV and other sexually transmitted infections (STI) was conducted. Out of 1,277 persons prescreened for eligibility, 625 were enrolled.

Results

HIV prevalence of all persons who completed screening was 14.8% (females: 21.1%; males: 8.1%). The odds of being enrolled in the study were higher for persons 18–24 years compared to those 30–34 years of age [adjusted odds ratio (AOR)=2.18, CI=1.13, 4.21] and males compared to females [AOR=2.07, CI=1.43, 2.99]. Among those enrolled in the study, the most prevalent HIV risk behaviors were unprotected sex (49%), alcohol use (45%), and transactional sex (30%) in the last three months. Compared to females, a significantly greater proportion of males reported using any alcohol or recreational drug in the last three months, a history of oral sex, sex with partner other than a spouse or main partner, ever having a blood transfusion, ever being treated for an STI, and having knowledge of their last HIV test result.

Conclusion

The Kisumu Field Station successfully recruited individuals with HIV risk characteristics for the HIV incidence cohort study.

Voluntary medical male circumcision: an HIV prevention priority for PEPFAR

As the science demonstrating strong evidence for voluntary medical male circumcision (VMMC) for HIV prevention has evolved, the President's Emergency Plan for AIDS Relief (PEPFAR) has collaborated with international agencies, donors, and partner country governments supporting VMMC programming. Mathematical models forecast that quickly reaching a large number of uncircumcised men with VMMC in strategically chosen populations may dramatically reduce community-level HIV incidence and save billions of dollars in HIV care and treatment costs. Because VMMC is a 1-time procedure that confers life-long partial protection against HIV, programs for adult men are vital short-term investments with long-term benefits. VMMC also provides a unique opportunity to reach boys and men with HIV testing and counseling services and referrals for other HIV services, including treatment. After formal recommendations by WHO in 2007, priority countries have pursued expansion of VMMC. More than 1 million males have received VMMC thus far, with the most notable successes coming from Kenya's Nyanza Province. However, a myriad of necessary cultural, political, and ethical considerations have moderated the pace of overall success. Because many millions more uncircumcised men would benefit from VMMC services now, US President Barack Obama committed PEPFAR to provide 4.7 million males with VMMC by 2014. Innovative circumcision methods-such as medical devices that remove the foreskin without injected anesthesia and/or sutures-are being rigorously evaluated. Incorporation of safe innovations into surgical VMMC programs may provide the opportunity to reach more men more quickly with services and dramatically reduce HIV incidence for all.

Willingness to participate in biomedical HIV prevention studies after the HVTN 503/Phambili trial: a survey conducted among adolescents in Soweto, South Africa

OBJECTIVES

Adolescents may be appropriate for inclusion in biomedical HIV prevention trials. Adolescents' overall willingness to participate (WTP) in biomedical HIV prevention trials was examined, including after the prematurely discontinued phase IIb HVTN 503/Phambili HIV vaccine trial, in Soweto, South Africa.

METHODS

An interview-administered cross-sectional survey was conducted among 506 adolescents (16-18 years) between October 2008 and March 2009. The assessment included WTP in HIV prevention trials, sexual and substance use behavior, and related psychosocial constructs. Multivariate logistic regression analyses examined predictors of WTP in biomedical prevention trials.

RESULTS

The sample primarily consisted of female participants (n = 298, 59%), and 50% of all participants were sexually active. WTP in general was high (93%), with 75% WTP in a vaccine trial after being informed about the HVTN 503/Phambili trial. Less exposure to stressors [odds ratio (OR): 2.8, confidence interval (CI): 1.3 to 6.3] was associated with adolescents' WTP in HIV biomedical prevention trials overall. Those with less exposure to stressors (OR: 1.7, CI: 1.1 to 2.8) and not sexually active (OR: 2.1, CI: 1.4 to 3.3) were predictive of WTP after the HVTN 503/Phambili trial. A higher number of sexual partners were associated with unwillingness to participate more generally (P = 0.039) and specifically after the HIV vaccine trial (P = 0.0004).

CONCLUSIONS

The high level of adolescents' WTP in biomedical prevention trials is encouraging, especially after the prematurely discontinued HVTN 503/Phambili HIV vaccine trial. High-risk youth were less likely to be WTP, although those not yet sexually active were more WTP. Future biomedical HIV prevention trials should address challenges to enrollment of high-risk adolescents who may show less WTP.

Circumcision preference among women and uncircumcised men prior to scale-up of male circumcision for HIV prevention in Kisumu, Kenya

Following the endorsement by the World Health Organization (WHO) and the Joint United Nations Programme on HIV/AIDS (UNAIDS) of male circumcision as an additional strategy to HIV prevention, initiatives to introduce safe, voluntary medical male circumcision (VMMC) services commenced in 2008 in several sub-Saharan African communities. Information regarding perceptions of circumcision as a method of HIV prevention, however, is largely limited to data collected before this important endorsement and the associated increase in the availability of VMMC services. To address this, we completed a community-based survey of male circumcision (MC) perceptions in the major non-circumcising community in Kenya, which is the current focus of VMMC programs in the country. Data was collected between November 2008 and April 2009, immediately before VMMC program scale-up commenced. Here we present results limited to women (n = 1088) and uncircumcised males (n = 460) to provide insight into factors contributing to the acceptability and preference for MC in those targeted by VMMC programs. Separate multivariable models examining preference for circumcision were defined for married men, unmarried men, and women. Belief in the protective effect of circumcision on HIV risk was strongly associated with preference for MC in all models. Other important factors included education, perceived improvement in sexual pleasure, and perceptions of impact on condom utilization. Identified barriers to circumcision were the belief that circumcision was not part of the local culture, the perception of a long healing period following the procedure, the lack of a specific impetus to seek out services, and the general fear of pain associated with becoming circumcised. A minority of participants expressed beliefs suggesting that behavioral risk compensation with increased MC prevalence and awareness is a possibility. This work describes the early impact of a large-scale VMMC program on beliefs and behaviors regarding MC and HIV risk. It is hoped that our findings may offer guidance into anticipating potential impacts that similar programs may observe in populations throughout Eastern Africa.

No evidence of association between HIV-1 and malaria in populations with low HIV-1 prevalence

BACKGROUND

The geographic overlap between HIV-1 and malaria has generated much interest in their potential interactions. A variety of studies have evidenced a complex HIV-malaria interaction within individuals and populations that may have dramatic effects, but the causes and implications of this co-infection at the population level are still unclear. In a previous publication, we showed that the prevalence of malaria caused by the parasite Plasmodium falciparum is associated with HIV infection in eastern sub-Saharan Africa. To complement our knowledge of the HIV-malaria co-infection, the objective of this work was to assess the relationship between malaria and HIV prevalence in the western region of sub-Saharan Africa.

METHODOLOGY/PRINCIPAL FINDINGS

Population-based cross-sectional data were obtained from the HIV/AIDS Demographic and Health Surveys conducted in Burkina Faso, Ghana, Guinea, Mali, Liberia and Cameroon, and the malaria atlas project. Using generalized linear mixed models, we assessed the relationship between HIV-1 and Plasmodium falciparum parasite rate (PfPR) adjusting for important socio-economic and biological cofactors. We found no evidence that individuals living in areas with stable malaria transmission (PfPR>0.46) have higher odds of being HIV-positive than individuals who live in areas with PfPR≤0.46 in western sub-Saharan Africa (estimated odds ratio 1.14, 95% confidence interval 0.86-1.50). In contrast, the results suggested that PfPR was associated with being infected with HIV in Cameroon (estimated odds ratio 1.56, 95% confidence interval 1.23-2.00).

CONCLUSION/SIGNIFICANCE

Contrary to our previous research on eastern sub-Saharan Africa, this study did not identify an association between PfPR and infection with HIV in western sub-Saharan Africa, which suggests that malaria might not play an important role in the spread of HIV in populations where the HIV prevalence is low. Our work highlights the importance of understanding the epidemiologic effect of co-infection and the relevant factors involved in this relationship for the implementation of effective control strategies.

Scaling up circumcision programs in Southern Africa: the potential impact of gender disparities and changes in condom use behaviors on heterosexual HIV transmission

Circumcision significantly reduces female-to-male transmission of HIV infection, but changes in behavior may influence the overall impact on transmission. We sought to explore these effects, particularly for societies where women have less power to negotiate safe sex. We developed a compartmental epidemic model to simulate the population-level impact of various circumcision programs on heterosexual HIV transmission in Soweto. We incorporated gender-specific negotiation of condom use in sexual partnerships and explored post-circumcision changes in condom use. A 5-year prevention program in which only an additional 10% of uncircumcised males undergo circumcision each year, for example, would prevent 13% of the expected new HIV infections over 20 years. Outcomes were sensitive to potential changes in behavior and differed by gender. For Southern Africa, even modest programs offering circumcision would result in significant benefits. Because decreases in male condom use could diminish these benefits, particularly for women, circumcision programs should emphasize risk-reduction counseling.

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.

Male circumcision and HIV infection risk

BACKGROUND

Male circumcision is being promoted to reduce human immunodeficiency virus type 1 (HIV) infection rates. This review evaluates the scientific evidence suggesting that male circumcision reduces HIV infection risk in high-risk heterosexual populations.

METHODS

We followed the updated International Consultation on Urological Diseases evidence-based medicine recommendations to critically review the scientific evidence on male circumcision and HIV infection risk.

RESULTS

Level 1 evidence supports the concept that male circumcision substantially reduces the risk of HIV infection. Three major lines of evidence support this conclusion: biological data suggesting that this concept is plausible, data from observational studies supported by high-quality meta-analyses, and three randomized clinical trials supported by high-quality meta-analyses.

CONCLUSIONS

The evidence from these biological studies, observational studies, randomized controlled clinical trials, meta-analyses, and cost-effectiveness studies is conclusive. The challenges to implementation of male circumcision as a public health measure in high-risk populations must now be faced.

Male circumcision in the general population of Kisumu, Kenya: beliefs about protection, risk behaviors, HIV, and STIs

Using a population-based survey we examined the behaviors, beliefs, and HIV/HSV-2 serostatus of men and women in the traditionally non-circumcising community of Kisumu, Kenya prior to establishment of voluntary medical male circumcision services. A total of 749 men and 906 women participated. Circumcision status was not associated with HIV/HSV-2 infection nor increased high risk sexual behaviors. In males, preference for being or becoming circumcised was associated with inconsistent condom use and increased lifetime number of sexual partners. Preference for circumcision was increased with understanding that circumcised men are less likely to become infected with HIV.

Assessing the impact of mass rape on the incidence of HIV in conflict-affected countries

OBJECTIVES

To quantify the potential impact of mass rape on HIV incidence in seven conflict-afflicted countries (CACs), with severe HIV epidemics, in sub-Saharan Africa.

DESIGN

Uncertainty analysis of a risk equation model.

METHODS

A mathematical model was used to evaluate the potential impact of mass rape on increasing HIV incidence in women and girls in Burundi, Democratic Republic of Congo (DRC), Rwanda, Sierra Leone, Somalia, southern Sudan and Uganda. The model was parameterized with data from UNAIDS/WHO and the US Census Bureau's International Database. Incidence data from UNAIDS/WHO were used for calibration.

RESULTS

Mass rape could cause approximately five HIV infections per 100,000 females per year in the DRC, Sudan, Somalia and Sierra Leone, double the number in Burundi and Rwanda, and quadruple the number in Uganda. The number of females infected per year due to mass rape is likely to be relatively low in Somalia and Sierra Leone at 127 [median (interquartile range [IQR] 55-254)] and 156 [median (IQR 69-305)], respectively. Numbers could be high in the DRC and Uganda: 1120 [median (IQR 527-2360)] and 2172 [median (IQR 1031-4668)], respectively. In Burundi, Rwanda and Sudan, the numbers are likely to be intermediate. Under extreme conditions, 10,000 women and girls could be infected per year in the DRC and 20 000 women and girls could be infected per year in Uganda. Mass rape could increase annual incidence by approximately 7% [median (IQR 3-15)].

CONCLUSION

Interventions and treatment targeted to rape survivors during armed conflicts could reduce HIV incidence. Support should be provided both on the basis of human rights and public health.

Will circumcision provide even more protection from HIV to women and men? New estimates of the population impact of circumcision interventions

BACKGROUND

Mathematical modelling has indicated that expansion of male circumcision services in high HIV prevalence settings can substantially reduce population-level HIV transmission. However, these projections need revision to incorporate new data on the effect of male circumcision on the risk of acquiring and transmitting HIV.

METHODS

Recent data on the effect of male circumcision during wound healing and the risk of HIV transmission to women were synthesised based on four trials of circumcision among adults and new observational data of HIV transmission rates in stable partnerships from men circumcised at younger ages. New estimates were generated for the impact of circumcision interventions in two mathematical models, representing the HIV epidemics in Zimbabwe and Kisumu, Kenya. The models did not capture the interaction between circumcision, HIV and other sexually transmitted infections.

RESULTS

An increase in the risk of HIV acquisition and transmission during wound healing is unlikely to have a major impact of circumcision interventions. However, it was estimated that circumcision confers a 46% reduction in the rate of male-to-female HIV transmission. If this reduction begins 2 years after the procedure, the impact of circumcision is substantially enhanced and accelerated compared with previous projections with no such effect-increasing by 40% the infections averted by the intervention overall and doubling the number of infections averted among women.

CONCLUSIONS

Communities, and especially women, may benefit much more from circumcision interventions than had previously been predicted, and these results provide an even greater imperative to increase scale-up of safe male circumcision services.

Male circumcision for the prevention of acquisition and transmission of sexually transmitted infections: the case for neonatal circumcision

The American Academy of Pediatrics (AAP) male circumcision policy states that while there are potential medical benefits of newborn male circumcision, the data are insufficient to recommend routine neonatal circumcision. Since 2005, however, 3 randomized trials have evaluated male circumcision for prevention of sexually transmitted infections. The trials found that circumcision decreases human immunodeficiency virus acquisition by 53% to 60%, herpes simplex virus type 2 acquisition by 28% to 34%, and human papillomavirus prevalence by 32% to 35% in men. Among female partners of circumcised men, bacterial vaginosis was reduced by 40%, and Trichomonas vaginalis infection was reduced by 48%. Genital ulcer disease was also reduced among males and their female partners. These findings are also supported by observational studies conducted in the United States. The AAP policy has a major impact on neonatal circumcision in the United States. This review evaluates the recent data that support revision of the AAP policy to fully reflect the evidence of long-term health benefits of male circumcision.

HIV prevalence and associated risk factors among individuals aged 13-34 years in Rural Western Kenya

OBJECTIVES

To estimate HIV prevalence and characterize risk factors among young adults in Asembo, rural western Kenya.

DESIGN

Community-based cross-sectional survey.

METHODS

From a demographic surveillance system, we selected a random sample of residents aged 13-34 years, who were contacted at home and invited to a nearby mobile study site. Consent procedures for non-emancipated minors required assent and parental consent. From October 2003 - April 2004, consenting participants were interviewed on risk behavior and tested for HIV and HSV-2. HIV voluntary counseling and testing was offered.

RESULTS

Of 2606 eligible residents, 1822 (70%) enrolled. Primary reasons for refusal included not wanting blood taken, not wanting to learn HIV status, and partner/parental objection. Females comprised 53% of 1762 participants providing blood. Adjusted HIV prevalence was 15.4% overall: 20.5% among females and 10.2% among males. HIV prevalence was highest in women aged 25-29 years (36.5%) and men aged 30-34 years (41.1%). HSV-2 prevalence was 40.0% overall: 53% among females, 25.8% among males. In multivariate models stratified by gender and marital status, HIV infection was strongly associated with age, higher number of sex partners, widowhood, and HSV-2 seropositivity.

CONCLUSIONS

Asembo has extremely high HIV and HSV-2 prevalence, and probable high incidence, among young adults. Further research on circumstances around HIV acquisition in young women and novel prevention strategies (vaccines, microbicides, pre-exposure prophylaxis, HSV-2 prevention, etc.) are urgently needed.

Herpes simplex virus type 2 and syphilis infections with HIV: an evolving synergy in transmission and prevention

PURPOSE OF REVIEW

Herpes simplex virus type 2 (HSV-2) and syphilis are associated with HIV infection. The purpose of this review is to summarize the advances in the relationship of HSV-2 and syphilis with HIV, highlighting intervention trials to prevent HIV acquisition and transmission.

RECENT FINDINGS

HIV acquisition has often been linked to genital ulcers due to HSV-2 and syphilis. The latest pathophysiological studies have continued to elucidate the relationship between HSV-2, syphilis and HIV, establishing that both syphilitic and HSV-2-infected tissue have increased numbers of chemokine receptor 5-expressing T cells, and several models have further emphasized the viral synergy between HSV-2 and HIV. In clinical trials, HSV suppressive therapy decreased HIV RNA levels that might affect transmission, but two trials have failed to prevent HIV acquisition. Male circumcision, however, prevents both HIV and HSV-2 acquisition.

SUMMARY

Genital ulcers from HSV-2 and syphilis are associated with HIV acquisition. The exact role for these HIV cofactors is still unknown and exemplified by the failure of HSV suppressive therapy to decrease HIV acquisition. Male circumcision, however, reduces HSV-2 acquisition. With several HSV suppressive trials to prevent HIV transmission and disease progression currently ongoing, the future promises to provide more critical information for the control of HIV infection.

Knowledge of HIV survival on skin-piercing instruments among young adults in Nyanza Province, Kenya

In countries with generalized HIV epidemics, people may be exposed to blood-borne HIV at their home as well as during health care and cosmetic services. We asked young adults from the Luo and Kisii ethnic groups in Nyanza Province, Kenya, how long HIV survives in blood and how to clean skin-piercing instruments. Only 21% thought that HIV could survive more than an hour in dry conditions (although it can survive for days), and only 24% thought it could survive more than a week in wet conditions (although it can survive more than four weeks). The Kisii, with lower HIV prevalence, were more knowledgeable than the Luo about HIV survival. Survey participants reported that barbers and other service providers often cleaned instruments by wiping with alcohol or bleach, a practice which does not reliably inactivate HIV. People we interviewed, at risk from blood-borne HIV, did not know enough to protect themselves.

Male circumcision and Neisseria gonorrhoeae, Chlamydia trachomatis and Trichomonas vaginalis: observations after a randomised controlled trial for HIV prevention

OBJECTIVE

To assess the association between male circumcision and Neisseria gonorrhoeae, Chlamydia trachomatis and Trichomonas vaginalis using data from a male circumcision randomised controlled trial.

METHODS

We used data collected during the male circumcision trial conducted in Orange Farm (South Africa) among men aged 18-24 years. Altogether, 1767 urine samples collected during the final follow-up visit were analysed using PCR. Prevalence of N gonorrhoeae, C trachomatis and T vaginalis was assessed as a function of male circumcision using odds ratios (OR) given by univariate and multivariate logistic regression.

RESULTS

In an intention-to-treat analysis, prevalence of N gonorrhoeae, C trachomatis and T vaginalis among intervention and control groups were 10.0% versus 10.3% (OR 0.97; p = 0.84), 2.1% versus 3.6% (OR 0.58; p = 0.065) and 1.7% versus 3.1% (OR 0.54; p = 0.062), respectively. The association between T vaginalis and male circumcision remained borderline when controlling for age, ethnic group, number of lifetime partners, marital status, condom use and HIV status (AOR 0.48; p = 0.069). In the as-treated analysis, this association became significant (OR 0.49, p = 0.030; AOR 0.41, p = 0.030).

CONCLUSIONS

This study demonstrates for the first time that male circumcision reduces T vaginalis infection among men. This finding explains why women with circumcised partners are less at risk for T vaginalis infection than other women. The protective effect on T vaginalis is an additional argument to recommend male circumcision in Africa where it is acceptable.

Male circumcision for the prevention of HSV-2 and HPV infections and syphilis

BACKGROUND

Male circumcision significantly reduced the incidence of human immunodeficiency virus (HIV) infection among men in three clinical trials. We assessed the efficacy of male circumcision for the prevention of herpes simplex virus type 2 (HSV-2) and human papillomavirus (HPV) infections and syphilis in HIV-negative adolescent boys and men.

METHODS

We enrolled 5534 HIV-negative, uncircumcised male subjects between the ages of 15 and 49 years in two trials of male circumcision for the prevention of HIV and other sexually transmitted infections. Of these subjects, 3393 (61.3%) were HSV-2-seronegative at enrollment. Of the seronegative subjects, 1684 had been randomly assigned to undergo immediate circumcision (intervention group) and 1709 to undergo circumcision after 24 months (control group). At baseline and at 6, 12, and 24 months, we tested subjects for HSV-2 and HIV infection and syphilis, along with performing physical examinations and conducting interviews. In addition, we evaluated a subgroup of subjects for HPV infection at baseline and at 24 months.

RESULTS

At 24 months, the cumulative probability of HSV-2 seroconversion was 7.8% in the intervention group and 10.3% in the control group (adjusted hazard ratio in the intervention group, 0.72; 95% confidence interval [CI], 0.56 to 0.92; P=0.008). The prevalence of high-risk HPV genotypes was 18.0% in the intervention group and 27.9% in the control group (adjusted risk ratio, 0.65; 95% CI, 0.46 to 0.90; P=0.009). However, no significant difference between the two study groups was observed in the incidence of syphilis (adjusted hazard ratio, 1.10; 95% CI, 0.75 to 1.65; P=0.44).

CONCLUSIONS

In addition to decreasing the incidence of HIV infection, male circumcision significantly reduced the incidence of HSV-2 infection and the prevalence of HPV infection, findings that underscore the potential public health benefits of the procedure. (ClinicalTrials.gov numbers, NCT00425984 and NCT00124878.)

Exploratory study of blood exposures that are risks for HIV among Luo and Kisii ethnic groups in Nyanza province, Kenya

Adult HIV prevalence exceeds 5% among all Kenyans, and 20% among the Luo ethnic group. Recent studies have associated HIV infections in Kenya with several invasive health care and cosmetic procedures. To explore the various blood exposures that could contribute to HIV infections in Kenya, we surveyed 320 adolescents and adults aged 15-29 years from the Luo and Kisii ethnic groups. Survey participants reported a wide range of invasive procedures in health care (including circumcisions, dental care, blood tests, and 1-60 injections or infusions for specific health problems), in cosmetic services (including tattooing and piercing) and around the home (through shaving body hair, fights, sports and other activities). Luo were significantly more likely than Kisii to report some risks (e.g. tattooing by a traditional expert, piercing), but less likely to report others (e.g. blood tests for malaria, anaesthetic injections during circumcision).

Genetic analysis of HIV-1 subtypes in Nairobi, Kenya

Background

Genetic analysis of a viral infection helps in following its spread in a given population, in tracking the routes of infection and, where applicable, in vaccine design. Additionally, sequence analysis of the viral genome provides information about patterns of genetic divergence that may have occurred during viral evolution.

Objective

In this study we have analyzed the subtypes of Human Immunodeficiency Virus -1 (HIV-1) circulating in a diverse sample population of Nairobi, Kenya.

Methodology

69 blood samples were collected from a diverse subject population attending the Aga Khan University Hospital in Nairobi, Kenya. Total DNA was extracted from peripheral blood mononuclear cells (PBMCs), and used in a Polymerase Chain Reaction (PCR) to amplify the HIV gag gene. The PCR amplimers were partially sequenced, and alignment and phylogenetic analysis of these sequences was performed using the Los Alamos HIV Database.

Results

Blood samples from 69 HIV-1 infected subjects from varying ethnic backgrounds were analyzed. Sequence alignment and phylogenetic analysis showed 39 isolates to be subtype A, 13 subtype D, 7 subtype C, 3 subtype AD and CRF01_AE, 2 subtype G and 1 subtype AC and 1 AG. Deeper phylogenetic analysis revealed HIV subtype A sequences to be highly divergent as compared to subtypes D and C.

Conclusion

Our analysis indicates that HIV-1 subtypes in the Nairobi province of Kenya are dominated by a genetically diverse clade A. Additionally, the prevalence of highly divergent, complex subtypes, intersubtypes, and the recombinant forms indicates viral mixing in Kenyan population, possibly as a result of dual infections.

Genital herpes has played a more important role than any other sexually transmitted infection in driving HIV prevalence in Africa

Background

Extensive evidence from observational studies suggests a role for genital herpes in the HIV epidemic. A number of herpes vaccines are under development and several trials of the efficacy of HSV-2 treatment with acyclovir in reducing HIV acquisition, transmission, and disease progression have just reported their results or will report their results in the next year. The potential impact of these interventions requires a quantitative assessment of the magnitude of the synergy between HIV and HSV-2 at the population level.

Methods and Findings

A deterministic compartmental model of HIV and HSV-2 dynamics and interactions was constructed. The nature of the epidemiologic synergy was explored qualitatively and quantitatively and compared to other sexually transmitted infections (STIs). The results suggest a more substantial role for HSV-2 in fueling HIV spread in sub-Saharan Africa than other STIs. We estimate that in settings of high HSV-2 prevalence, such as Kisumu, Kenya, more than a quarter of incident HIV infections may have been attributed directly to HSV-2. HSV-2 has also contributed considerably to the onward transmission of HIV by increasing the pool of HIV positive persons in the population and may explain one-third of the differential HIV prevalence among the cities of the Four City study. Conversely, we estimate that HIV had only a small net impact on HSV-2 prevalence.

Conclusions

HSV-2 role as a biological cofactor in HIV acquisition and transmission may have contributed substantially to HIV particularly by facilitating HIV spread among the low-risk population with stable long-term sexual partnerships. This finding suggests that prevention of HSV-2 infection through a prophylactic vaccine may be an effective intervention both in nascent epidemics with high HIV incidence in the high risk groups, and in established epidemics where a large portion of HIV transmission occurs in stable partnerships.

Update on male circumcision: prevention success and challenges ahead

This article reviews the findings of three trials of male circumcision for HIV prevention, with emphasis on the public health impact, cultural and safety concerns, implications for women, and the challenges of roll out. Three randomized trials in Africa demonstrated that adult male circumcision reduces HIV acquisition by 50% to 60%. As circumcision provides only partial protection, higher risk behaviors could nullify circumcision's effect. Additionally, circumcision among HIV-infected men does not directly reduce male-to-female HIV transmission among discordant couples, according to the results of a recent Ugandan study. The roll-out or full-scale implementation requires committed expansion into existing HIV prevention programs. Efforts should include attention to safety, implications for women, and risk compensation. Rapid, careful establishment of circumcision services is essential to optimize HIV prevention in countries with the highest prevalence.

Treating curable sexually transmitted infections to prevent HIV in Africa: still an effective control strategy?

BACKGROUND

Evidence regarding the effectiveness of sexually transmitted infection (STI) treatment for HIV prevention in Africa is equivocal, leading some policy makers to question whether it should continue to be promoted for HIV control. We explore whether treating curable STIs remains a cost-effective HIV control strategy in Africa.

METHODS

The model STDSIM was fitted to the characteristics of 4 populations in East and West Africa. Over the simulated HIV epidemics, the population-attributable fractions (PAFs) of incident HIV attributable to STIs, the impact of syndromic STI management on HIV incidence, and the cost per HIV infection averted were evaluated and compared with an estimate of lifetime HIV treatment costs (US $3500).

RESULTS

Throughout the HIV epidemics in all cities, the total PAF for. all STIs remained high, with > or = 50% of HIV transmission attributed to STIs. The PAF for herpes simplex virus type 2 increased during the epidemics, whereas the PAF for curable STIs and the relative impact of syndromic management decreased. The models showed that the absolute impact of syndromic management remains high in generalized epidemics, and it remained cost-saving in 3 of the 4 populations in which the cost per HIV infection averted ranged between US $321 and $1665.

CONCLUSION

Curable STI interventions may remain cost-saving in populations with generalized HIV epidemics, particularly in populations with high-risk behaviors or low male circumcision rates.