***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: BACKGROUND This paper aims to describe factors associated with HIV sero-status in young , rural South African women and the relationship between intimate partner violence ( IPV ) and HIV . METHODS A total of 1295 sexually active female volunteers , aged 15 - 26 , from 70 villages were recruited to participate in a cluster r and omized controlled trial of an HIV behavioural intervention . The main measures were HIV sero-status , and IPV and sexual practice s measured using a question naire administered during baseline interviews . RESULTS About 12.4 % of women had HIV and 26.6 % had experienced more than one episode of physical or sexual IPV . After adjusting for age , HIV infection was associated with having three or more past year partners [ odds ratio ( OR ) 2.39 ; 95 % confidence interval ( 95 % CI ) 1.48 - 3.85 ] , sex in past 3 months ( OR 3.33 ; 95 % CI 1.87 - 5.94 ) , a partner three or more years older ( OR 1.69 ; 95 % CI 1.16 - 2.48 ) , and a more educated partner ( OR 1.91 ; 95 % CI 1.30 - 2.78 ) . IPV was associated with HIV in two-way analyses ( OR 1.56 ; 95 % CI 1.08 - 2.23 ) , but the effect was non-significant after adjusting for HIV risk behaviours . The experience of IPV was strongly associated with past year partner numbers , time of last sex , and partner 's education ; it was also marginally associated with partner age difference . Adverse experiences in childhood , including sexual abuse , increased the likelihood of having more past year partners ( OR 1.43 ; 95 % CI 1.21 - 1.69 ) . CONCLUSIONS IPV was strongly associated with most of the identified HIV risk factors . Our findings provide further evidence of links between IPV and HIV among women and the importance of joint prevention Objective To assess the impact of Stepping Stones , a HIV prevention programme , on incidence of HIV and herpes simplex type 2 ( HSV-2 ) and sexual behaviour . Design Cluster r and omised controlled trial . Setting 70 villages ( clusters ) in the Eastern Cape province of South Africa . Participants 1360 men and 1416 women aged 15 - 26 years , who were mostly attending schools . Intervention Stepping Stones , a 50 hour programme , aims to improve sexual health by using participatory learning approaches to build knowledge , risk awareness , and communication skills and to stimulate critical reflection . Villages were r and omised to receive either this or a three hour intervention on HIV and safer sex . Interviewers administered question naires at baseline and 12 and 24 months and blood was tested for HIV and HSV-2 . Main outcome measures Primary outcome measure : incidence of HIV . Other outcomes : incidence of HSV-2 , unwanted pregnancy , reported sexual practice s , depression , and substance misuse . Results There was no evidence that Stepping Stones lowered the incidence of HIV ( adjusted incidence rate ratio 0.95 , 95 % confidence interval 0.67 to 1.35 ) . The programme was associated with a reduction of about 33 % in the incidence of HSV-2 ( 0.67 , 0.46 to 0.97 ; P=0.036)—that is , Stepping Stones reduced the number of new HSV-2 infections over a two year period by 34.9 ( 1.6 to 68.2 ) per 1000 people exposed . Stepping Stones significantly improved a number of reported risk behaviours in men , with a lower proportion of men reporting perpetration of intimate partner violence across two years of follow-up and less transactional sex and problem drinking at 12 months . In women desired behaviour changes were not reported and those in the Stepping Stones programme reported more transactional sex at 12 months . Conclusion Stepping Stones did not reduce incidence of HIV but had an impact on several risk factors for HIV — notably , HSV-2 and perpetration of intimate partner violence . Trial Registration Clinical Trials NCT00332878 OBJECTIVE To describe factors associated with  HIV infection in men aged 15 - 26 years . SETTING Rural Eastern Cape Province , South Africa . SAMPLE A total of 1277 sexually experienced Xhosa male volunteers from 70 villages participating in a cluster r and omized controlled trial of an HIV behavioural intervention . Xhosas circumcise during manhood initiation rituals . DESIGN Cross-sectional , analysis of the study 's baseline interviews . MAIN MEASURE HIV sero-status , sexual practice s measured with an interviewer-administered question naire . RESULTS About 2 % of the men were HIV positive . A logistic regression model showed HIV positivity to be associated with age ( OR 1.55 ; 95%CI 1.22 - 1.95 ) , having made a woman pregnant ( OR 2.93 ; 95 % CI 1.28 - 6.68 ) , having been circumcised ( OR 0.40 ; 95 % CI 0.16 - 0.98 ) , and having had sex with a man ( OR 3.61 ; 95 % CI 1.0 - 13.0 ) . CONCLUSIONS Our findings provide further evidence to suggest that circumcision is protective . There was much heterosexual risk taking among men but only pregnancy ( with its association with sexual frequency ) predicted HIV sero-positivity . Although relatively rare , same-sex sexual experiences were a risk factor . Male-male sexual contact is rarely assessed in HIV research in Africa and almost never addressed in general HIV prevention programming . Our findings suggest that it should be given more attention BACKGROUND Lack of education and an economic dependence on men are often suggested as important risk factors for HIV infection in women . We assessed the efficacy of a cash transfer programme to reduce the risk of sexually transmitted infections in young women . METHODS In this cluster r and omised trial , never-married women aged 13 - 22 years were recruited from 176 enumeration areas in the Zomba district of Malawi and r and omly assigned with computer-generated r and om numbers by enumeration area ( 1:1 ) to receive cash payments ( intervention group ) or nothing ( control group ) . Intervention enumeration areas were further r and omly assigned with computer-generated r and om numbers to conditional ( school attendance required to receive payment ) and unconditional ( no requirements to receive payment ) groups . Participants in both intervention groups were r and omly assigned by a lottery to receive monthly payments ranging from US$ 1 to $ 5 , while their parents were independently assigned with computer-generated r and om numbers to receive $ 4 - 10 .  Behavioural risk assessment  s were done at baseline and 12 months ; serology was tested at 18 months . Participants were not masked to treatment status but counsellors doing the serologic testing were . The primary outcomes were prevalence of HIV and herpes simplex virus 2 ( HSV-2 ) at 18 months and were assessed by intention-to-treat analyses . The trial is registered , number NCT01333826 . FINDINGS 88 enumeration areas were assigned to receive the intervention and 88 as controls . For the 1289 individuals enrolled in school at baseline with complete interview and biomarker data , weighted HIV prevalence at 18 month follow-up was 1·2 % ( seven of 490 participants ) in the combined intervention group versus 3·0 % ( 17 of 799 participants ) in the control group ( adjusted odds ratio [ OR ] 0·36 , 95 % CI 0·14 - 0·91 ) ; weighted HSV-2 prevalence was 0·7 % ( five of 488 participants ) versus 3·0 % ( 27 of 796 participants ; adjusted OR 0·24 , 0·09 - 0·65 ) . In the intervention group , we noted no difference between conditional versus unconditional intervention groups for weighted HIV prevalence ( 3/235 [ 1 % ] vs 4/255 [ 2 % ] ) or weighted HSV-2 prevalence ( 4/233 [ 1 % ] vs 1/255 [ < 1 % ] ) . For individuals who had already dropped out of school at baseline , we detected no significant difference between intervention and control groups for weighted HIV prevalence ( 23/210 [ 10 % ] vs 17/207 [ 8 % ] ) or weighted HSV-2 prevalence ( 17/211 [ 8 % ] vs 17/208 [ 8 % ] ) . INTERPRETATION Cash transfer programmes can reduce HIV and HSV-2 infections in adolescent schoolgirls in low-income setting s. Structural interventions that do not directly target sexual behaviour change can be important components of HIV prevention strategies . FUNDING Global Development Network , Bill & Melinda Gates Foundation , National Bureau of Economic Research Africa Project , World Bank 's Research Support Budget , and several World Bank trust funds ( Gender Action Plan , Knowledge for Change Program , and Spanish Impact Evaluation fund ) Background : Incidence data from prospect i ve cohort studies using rigorous laboratory methods are important in design ing and evaluating HIV vaccine and therapeutic clinical trials and health care programs . We report 36-month HIV-1 incidence rates and demographic and psychosocial risks from the Kericho cohort in rural Kenya 's southern Rift Valley Province . Methods : Thirty-six month , prospect i ve , closed , observational cohort study of adult plantation workers and dependents followed biannually . HIV-1 incidence rates per 100 person-years ( py ) were calculated , and Cox regression analyses were used to estimate hazards ratios ( HR ) associated with seroconversion . Results : Two thous and four hundred volunteers ( mean age ± SD = 30.1 ± 8.5 years ; 36.5 % women ) participated . Twenty-nine new HIV cases were identified in year 1 of follow-up , which increased to cumulative totals of 49 and 63 cases in years 2 and 3 , respectively . The corresponding 1- , 2- , and 3-year incidence rates were 1.41 [ 95 % confidence interval ( CI ) = 0.95 - 2.02 ] , 1.16 ( 95 % CI = 0.86 - 1.54 ) , and 1.00 ( 95 % CI = 0.77 - 1.28 ) per 100 py . Risk factors associated with HIV seroconversion included the following : of the Luo tribe ( HR = 3.31 ; 95 % CI = 1.65 - 6.63 ) , marriage more than once ( HR = 2.83 ; 95 % CI = 1.20 - 6.69 ) , self-reported male circumcision ( HR = 0.32 ; 95 % CI = 0.17 - 0.60 ) , history of sexually transmitted infection ( HR = 2.40 ; 95 % CI = 1.09 - 5.26 ) , history of substance abuse during sex ( HR = 2.44 ; 95 % CI = 1.16 - 5.13 ) , and history of transactional sex ( HR = 3.30 ; 95 % CI = 1.79 - 6.09 ) . Conclusions : HIV-1 incidence rates were relatively low in adult plantation workers and dependents in rural Kenya . Cohorts including higher risk population s ( eg , commercial sex workers ) warrant consideration for regional HIV preventive vaccine trials . Even low incidence , well-described cohorts generate valuable epidemiological clinical trial data Objective : To identify and describe population s at risk for HIV in 3 clinical research centers in Kenya and South Africa . Design : Prospect i ve cohort study . Methods : Volunteers reporting recent sexual activity , multiple partners , transactional sex , sex with an HIV-positive partner , or , if male , sex with men ( MSM ; in Kenya only ) were enrolled . Sexually active minors were enrolled in South Africa only .  Risk behavior , HIV testing , and clinical data were obtained at follow-up visits . Results : From 2005 to 2008 , 3023 volunteers were screened , 2113 enrolled , and 1834 contributed data on HIV incidence . MSM had the highest HIV incidence rate of 6.8 cases per 100 person-years [ 95 % confidence interval ( CI ) : 4.9 to 9.2 ] followed by women in Kilifi and Cape Town ( 2.7 cases per 100 person-years , 95 % CI : 1.7 to 4.2 ) . No seroconversions were observed in Nairobi women or men in Nairobi or Cape Town who were not MSM . In 327 MSM , predictors of HIV acquisition included report of genital ulcer ( Hazard Ratio : 4.5 , 95 % CI : 1.7 to 11.6 ) , not completing secondary school education ( HR : 3.4 , 95 % CI : 1.6 to 7.2 ) and reporting receptive anal intercourse ( HR : 8.2 , 95 % CI : 2.7 to 25.0 ) . Paying for sex was inversely associated with HIV infection ( HR : 0.2 , 95 % CI : 0.04 to 0.8 ) . 279 ( 13.0 % ) volunteers did not return after the first visit ; subsequent attrition rates ranged from 10.4 to 21.8 volunteers per 10 
    Output:
    
Conclusions Transactional sex is associated with HIV among women , whereas findings for men were inconclusive .