***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: A r and omized cross-over trial of herpes simplex virus type 2 (HSV-2)-suppressive therapy ( valacyclovir , 500 mg twice daily , or placebo for 8 weeks , a 2-week washout period , then the alternative therapy for 8 weeks ) was conducted among 20 Peruvian women coinfected with HSV-2 and human immunodeficiency virus type 1 ( HIV-1 ) who were not on antiretroviral therapy .  Plasma sample s ( obtained weekly ) and endocervical swab specimens ( obtained thrice weekly ) were collected for HIV-1 RNA polymerase chain reaction . Plasma HIV-1 level was significantly lower during the valacyclovir arm , compared with the placebo arm ( -0.26 log10 copies/mL , a 45 % decrease [ P < .001 ] ) , as was cervical HIV-1 level ( -0.35 log10 copies/swab , a 55 % decrease [ P < .001 ] ) . Suppressive HSV-2 therapy has the potential to reduce HIV-1 infectiousness and slow HIV-1 disease progression A r and omised trial was done to evaluate the impact of improved sexually transmitted disease ( STD ) case management at primary health care level on the  incidence of HIV infection in the rural Mwanza region of Tanzania .  HIV incidence was compared in six intervention communities and six pair-matched comparison communities . A r and om cohort of about 1000 adults aged 15 - 54 years from each community was surveyed at baseline and at follow-up 2 years later . Intervention consisted of establishment of an STD reference clinic , staff training , regular supply of drugs , regular supervisory visits to health facilities , and health education about STDs .  12,537 individuals were recruited .  Baseline HIV prevalences were 3.8 % and 4.4 % in the intervention and comparison communities , respectively . At follow-up , 8845 ( 71 % ) of the cohort were seen . Of those initially seronegative , the proportions seroconverting over 2 years were 48 of 4149 ( 1.2 % ) in the intervention communities and 82 of 4400 ( 1.9 % ) in the comparison communities . HIV incidence was consistently lower in the intervention communities in all six matched pairs . Allowing for the community-r and omised design and the effects of confounding factors , the estimated risk ratio was 0.58 ( 95 % CI 0.42 - 0.79 , p = 0.007 ) . No change in reported sexual behaviour was observed in either group . We conclude that improved STD treatment reduced HIV incidence by about 40 % in this rural population . This is the first r and omised trial to demonstrate an impact of a preventive intervention on HIV incidence in a general population Background Underst and ing the correlates of HIV shedding is important to inform strategies to reduce HIV infectiousness . We examined correlates of genital HIV-1 RNA in women who were seropositive for both herpes simplex virus (HSV)-2 and HIV-1 and who were enrolled in a r and omised controlled trial of HSV suppressive therapy ( aciclovir 400 mg b.i.d vs. placebo ) in Tanzania . Methodology Sample s , including a cervico-vaginal lavage , were collected and tested for genital HIV-1 and HSV and reproductive tract infections ( RTIs ) at r and omisation and 6 , 12 and 24 months follow-up . Data from all women at r and omisation and women in the placebo arm during follow-up were analysed using generalised estimating equations to determine the correlates of cervico-vaginal HIV-1 RNA detection and load . Principal Findings Cervico-vaginal HIV-1 RNA was detected at 52.0 % of 971 visits among 482 women , and was independently associated with plasma viral load , presence of genital ulcers , pregnancy , bloody cervical or vaginal discharge , abnormal vaginal discharge , cervical ectopy , Neisseria gonorrhoeae , Chlamydia trachomatis , Trichomonas vaginalis , an intermediate bacterial vaginosis score and HSV DNA detection . Similar factors were associated with genital HIV-1 RNA load . Conclusions RTIs were associated with increased presence and quantity of genital HIV-1 RNA in this population . These results highlight the importance of integrating effective RTI treatment into HIV care services To determine the frequency and risk factors for female to male sexual transmission of  human immunodeficiency virus type 1 ( HIV-1 ) , a prospect i ve study was carried out in 422 men who had acquired a sexually transmitted disease ( STD ) from a group of prostitutes with a prevalence of HIV-1 infection of 85 % . The initial seroprevalence of HIV among the men was 12 % . 24 of 293 ( 8.2 % ) initially seronegative men seroconverted to HIV-1 . Newly acquired infection was independently associated with frequent prostitute contact ( risk ratio 3.2 , 95 % confidence interval 1.2 - 8.1 ) , with the acquisition of genital ulcer disease ( risk ratio 4.7 , 95 % confidence interval 1.3 - 17.0 ) , and with being uncircumcised ( risk ratio 8.2 , 95 % confidence interval 3.0 - 23.0 ) . 96 % of documented seroconversions occurred in men with one or both of the latter two risk factors . In a subgroup of 73 seronegative men who reported a single prostitute sexual contact , the frequency of HIV-1 infection was 8.2 % during 12 weeks of observation . No man without a genital ulcer seroconverted . A cumulative 43 % of uncircumcised men who acquired an ulcer seroconverted to HIV-1 after a single sexual exposure . These data indicate an extremely high rate of female to male transmission of HIV-1 in the presence of STD and confirm a causal relation between lack of male circumcision , genital ulcer disease , and susceptibility to HIV-1 infection BACKGROUND Syphilis remains an important source of morbidity worldwide . Long-acting penicillin is the only therapy currently recommended for syphilis in much of the world . Because of hesitation to use penicillin for fear of anaphylaxis , there is a need for an effective , well-tolerated alternative to penicillin for syphilis therapy . METHODS This multicenter , r and omized clinical trial was conducted in clinics for the treatment of persons with sexually transmitted diseases . We compared serological cure rates for human immunodeficiency virus (HIV)-negative persons with early syphilis treated with azithromycin at a dosage of 2.0 g administered orally as a single dose with cure rates for those treated with benzathine penicillin G at a dosage of 2.4 million units administered intramuscularly . RESULTS A total of 517 participants were enrolled in the trial . In the intention-to-treat analysis , after 6 months of follow-up , serological cure was observed in 180 ( 77.6 % ) of 232 azithromycin recipients and 186 ( 78.5 % ) of 237 penicillin recipients ( 1-sided lower bound 95 % confidence interval , 7.2 % ) . Nonserious adverse events were more common among azithromycin recipients than they were among penicillin recipients ( 61.5 % vs 46.3 % ) , and such adverse events were accounted for , in large part , by self-limited gastrointestinal complaints . CONCLUSIONS In this trial , the efficacy of azithromycin at a dosage of 2.0 g administered orally was equivalent to that of benzathine penicillin G for the treatment of early syphilis in persons without HIV infection Genital ulcers are implicated as a risk factor enhancing susceptibility to human immunodeficiency virus type 1 ( HIV-1 ) infection . A prospect i ve study to determine the incidence of and risk factors associated with acquisition of HIV-1 in women with genital ulcers was done .  HIV-1-seronegative women with genital ulcers attending a clinic for sexually transmitted diseases in Nairobi were followed to HIV-1 seroconversion over a 6-month period . Of 81 women , 10 seroconverted to HIV-1 . The crude 6-month incidence of HIV-1 infection was 12 % . Risk factors associated with seroconversion included cervical ectopy ( rate ratio [ RR ] , 4.9 ; 95 % confidence interval [ CI ] , 1.5 - 15.6 ) and pelvic inflammatory disease ( RR , 6.3 ; 95 % CI , 1.9 - 20.4 ) . Thus , cervical ectopy and pelvic inflammatory disease may increase susceptibility to HIV-1 in women with genital ulcers Background : An association has been demonstrated between herpes simplex type 2 ( HSV-2 ) and HIV infection among men , but prospect i ve studies in women have yielded mixed results . Objective : To estimate the effects of prevalent and incident HSV-2 infection on subsequent HIV acquisition among women in two African countries . Design : Prospect i ve cohort study . Methods : HSV-2 and HIV serostatus were evaluated at enrollment and quarterly for 15–24 months among 4531 sexually active , HIV-uninfected women aged 18–35 years from Ug and a and Zimbabwe . The association between prior HSV-2 infection and HIV acquisition was estimated using a marginal structural discrete survival model , adjusted for covariates . Results : HSV-2 seroprevalence at enrollment was 52 % in Ug and a and 53 % in Zimbabwe ; seroincidence during follow-up was 9.6 and 8.8/100 person-years in Ug and a and Zimbabwe , respectively . In Ug and a , the hazard ratio ( HR ) for HIV was 2.8 [ 95 % confidence interval ( CI ) , 1.5–5.3 ] among women with seroprevalent HSV-2 and 4.6 ( 95 % CI , 1.6–13.1 ) among women with seroincident HSV-2 , adjusted for confounding . In Zimbabwe , the HR for HIV was 4.4 ( 95 % CI , 2.7–7.2 ) among women with seroprevalent HSV-2 , and 8.6 ( 95 % CI , 4.3–17.1 ) among women with seroincident HSV-2 , adjusted for confounding . The population attributable risk percent for HIV due to prevalent and incident HSV-2 infection was 42 % in Ug and a and 65 % in Zimbabwe . Conclusions : HSV-2 plays an important role in the acquisition of HIV among women . Efforts to implement known HSV-2 control measures , as well as identify additional measures to control HSV-2 , are urgently needed to curb the spread of HIV BACKGROUND Reports of neurosyphilis and invasion of cerebrospinal fluid by Treponema pallidum in patients with human immunodeficiency virus ( HIV ) infection have led to doubts about the adequacy of the recommended penicillin G benzathine therapy for early syphilis . METHODS In a multicenter , r and omized , double-blind trial , we assessed two treatments for early syphilis : 2.4 million units of penicillin G benzathine and that therapy enhanced with a 10-day course of amoxicillin and probenecid . The serologic and clinical responses of patients with and without HIV infection were studied during one year of follow-up . RESULTS From 1991 through 1994 , 541 patients were enrolled , including 101 patients ( 19 percent ) who had HIV infection but differed little from the uninfected patients in their clinical presentations . The rates at which chancres and rashes resolved did not differ significantly according to treatment assignment or HIV status . Serologically defined treatment failures were more common among the HIV-infected patients . The single clinical ly defined treatment failure was in an HIV-infected patient .  Rates of serologically defined treatment failure did not differ according to treatment group ( 18 percent at six months with usual therapy ; 17 percent with enhanced therapy ) . T. pallidum was found at enrollment in the cerebrospinal fluid of 32 of 131 patients ( 24 percent ) and after therapy in 7 of 35 patients tested . None had clinical ly evident neurosyphilis , and the rate of detection of T. pallidum did not differ according to HIV status . CONCLUSIONS After treatment for primary or secondary syphilis , the HIV-infected patients responded less well serologically than the patients without HIV infection , but clinical ly defined failure was uncommon in both groups . Enhanced treatment with amoxicillin and probenecid did not improve the outcomes . Although T. pallidum was detected in cerebrospinal fluid before therapy in a quarter of the patients tested , such a finding did not predict treatment failure . The current recommendations for treating early syphilis appear adequate for most patients , whether or not they have HIV infection Background : Several studies suggest that herpes simplex virus type 2 ( HSV-2 ) may enhance HIV-1 transmission and disease progression . Methods : We conducted a r and omized , double-blind , placebo-controlled trial of aciclovir 400 mg twice daily for 3 months in 300 HSV-2/HIV-1 co-infected women not yet on highly active antiretroviral 
    Output:
    
At present , there is insufficient evidence to determine whether curative treatment of genital ulcer disease would reduce the risk of HIV acquisition .
The very low quality of the evidence implies that the true effect of genital ulcer disease treatment on sexual acquisition of HIV may be substantially different from the effect estimated from currently available data .