Epidemiology and Social
Changes in sexual behavior and risk of HIV transmission after antiretroviral therapy and prevention interventions in rural Uganda
Bunnell, Rebeccaa; Ekwaru, John Paula; Solberg, Peterb; Wamai, Nafunaa; Bikaako-Kajura, Winniea; Were, Willya; Coutinho, Alexc; Liechty, Cherylb; Madraa, Elizabethd; Rutherford, Georgeb; Mermin, Jonathana
From the aCDC–Uganda, Global AIDS Program, National Center for HIV, STD and TB Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia
bUniversity of California, San Francisco, California, USA
cAIDS Support Organization, Kampala
dUganda Ministry of Health, Kampala, Uganda.
Received 6 May, 2005
Revised 8 July, 2005
Accepted 20 July, 2005
Correspondence to Dr. Rebecca Bunnell, Uganda Virus Research Institute, P.O. Box 49, Entebbe, Uganda E-mail: email@example.com
Background: The impact of antiretroviral therapy (ART) on sexual risk behavior and HIV transmission among HIV-infected persons in Africa is unknown.
Objective: To assess changes in risky sexual behavior and estimated HIV transmission from HIV-infected adults after 6 months of ART.
Design and methods: A prospective cohort study was performed in rural Uganda. Between May 2003 and December 2004 a total of 926 HIV-infected adults were enrolled and followed in a home-based ART program that included prevention counselling, voluntary counseling and testing (VCT) for cohabitating partners and condom provision. At baseline and follow-up, participants’ HIV plasma viral load and partner-specific sexual behaviors were assessed. Risky sex was defined as inconsistent or no condom use with partners of HIV-negative or unknown serostatus in the previous 3 months. The rates of risky sex were compared using a Poisson regression model and transmission risk per partner was estimated, based on established viral load-specific transmission rates.
Results: Six months after initiating ART, risky sexual behavior reduced by 70% [adjusted risk ratio, 0.3; 95% confidence interval (CI), 0.2–0.7; P = 0.0017]. Over 85% of risky sexual acts occurred within married couples. At baseline, median viral load among those reporting risky sex was 122 500 copies/ml, and at follow-up, < 50 copies/ml. Estimated risk of HIV transmission from cohort members declined by 98%, from 45.7 to 0.9 per 1000 person years.
Conclusions: Providing ART, prevention counseling, and partner VCT was associated with reduced sexual risk behavior and estimated risk of HIV transmission among HIV-infected Ugandan adults during the first 6 months of therapy. Integrated ART and prevention programs may reduce HIV transmission in Africa.
Access to antiretroviral therapy (ART) is increasing globally ; however the impact of ART on sexual risk behavior and transmission of HIV in Africa is unknown. Although ART may prevent HIV transmission through reduced infectivity , this could be offset by increases in risky sexual behaviour . In addition, cell-associated genital HIV shedding may occur in people with low plasma HIV viral load [4,5] allowing for the potential transmission of drug-resistant strains of HIV . Models developed for South Africa and Uganda have suggested that increases in risky sexual behavior by those initiating ART could reduce expected declines in HIV incidence [7,8]. HIV transmission from people on ART will depend on the effectiveness of ART in reducing viral load and of ART programs in reducing sexual risk behavior.
The association between taking ART and sexual behavior in industrialized countries is unclear. Some studies of men who have sex with men, heterosexual, and injecting drug user populations in the United States have demonstrated that risky sexual behaviors [9–11] and STI incidence  are higher among HIV-infected persons on ART than among those not on treatment. In contrast, other studies, including several from Europe, have shown significantly lower rates of risky sex among those on ART [13–16]. Aggregated data from 16 studies from industrialized countries showed that prevalence of unprotected sex was no higher among those receiving ART than those not on ART .
While ART has been shown to reduce viral load [18,19] and mortality[18,20] in Africa, its effect on risky sexual behavior has not been assessed in a prospective cohort . We assessed sexual behavior before and 6 months after initiation of ART in a cohort of 926 HIV-infected adults in rural Uganda, including: (1) factors associated with sexual activity; (2) changes in desire and frequency of sexual behavior after 6 months of ART; and (3) changes in estimated risk of HIV transmission based on viral load, risky sex, and established condom failure rates.
Between May 2003 and November 2004, we enrolled and followed persons with HIV-1 infection who were clients of the Tororo branch of The AIDS Support Organization (TASO), a non-governmental organization that has provided HIV/AIDS care and support since 1987. Registration at TASO is free. Forty-six percent of the general population in the Tororo area lives below the Ugandan poverty line, defined as a household's ability to meet minimum caloric requirements . Clients with a CD4 cell count ≤ 250 cells/μl or symptomatic AIDS (defined as CDC category B or C conditions) living within a 100 km2 catchment area were eligible for enrollment. We translated consent forms and questionnaires into six local languages. All participants and their household members provided written informed consent. We offered home-based HIV voluntary counseling and testing (VCT) to all participants’ household members at enrollment and after 1 year  and provided free ART for those clinically eligible.
The study includes a randomized ART efficacy monitoring trial evaluating clinical monitoring, clinical monitoring with quarterly CD4 cell count measurements, and clinical monitoring with quarterly CD4 cell counts and HIV viral load. Participants received weekly home-based ART delivery and monitoring by lay field officers and referral as needed for free medical and psychosocial care at the study clinic. The first line ART regimen was stavudine, lamivudine, and nevirapine or efavirenz. Results of this trial will be presented elsewhere.
The Uganda National Council of Science and Technology and the Institutional Review Boards of the Uganda Virus Research Institute, the University of California, San Francisco, and the Centers for Disease Control and Prevention (CDC) approved the study. Funding was provided by the US Department of Health and Human Services/CDC through the Emergency Plan for AIDS Relief.
Study design and procedures
At enrollment and every 3 months thereafter, study counselors conducted private home-based structured interviews with participants. Counselors were trained in rapport-building techniques and eliciting information from participants on sensitive topics in a non-judgmental manner. They asked participants about their sexual desire, opportunities to meet new partners, expectations for future sexual activity, and frequency of sex and condom use with each partner for the previous three months.
We obtained frequency of condom use for the prior 2 weeks as act-specific use of a condom and for the previous 3 months as ‘always’, ‘sometimes’, or ‘never’. The number of unprotected sexual acts in last 3 months was estimated from the frequency of sex and condom use for each partner. For those reporting ‘always’ using a condom with a particular partner, the number was estimated as zero unprotected sex acts. For those reporting ‘never’ using a condom with a partner, the frequency of sex with that partner was used for the estimate of unprotected sex acts. For those reporting ‘sometimes’ using a condom with a partner, the number of sex acts with and without a condom were estimated by multiplying the average 2-week condom coverage rate of all persons reporting sometimes using a condom and the frequency of sex with a specific sexual partner over the previous 3 months. Participants provided each sexual partner's HIV serostatus (tested positive, tested negative, unknown) and partner type (spouse, steady or casual partner). We defined abstinence as having no sexual intercourse during the prior 3 months and risky sex as participant-reported inconsistent condom use with a HIV-negative or unknown serostatus partner.
All participants received a behavioral intervention that included group education on ART at enrollment and testing of cohabitating partners through home-based family VCT. In individual sessions, participants developed personal sexual behavior plans in which they assessed their motivation for avoiding transmission and their current risk situation and made risk reduction plans that included how they might cope with increased sexual desires. Risk reduction options discussed by counselors included abstinence, condom use, reduced frequency of sex, and alternative forms of sexual expression. Counselling emphasized risk reduction with HIV-negative or unknown status partners and free condoms were provided to clients who requested them. Although participants had received some prevention counseling previously as TASO clients, partner VCT was not provided and emphasis was on avoiding re-infection.
We measured HIV plasma viral loads using Cobas Amplicor HIV-1 Monitor version 1.5 (Roche, Branchburg, New Jersey, USA) and enumerated CD4 cells using TriTEST reagents following an in-house dual platform protocol and MultiSET and Attractors software using a FACScan flow cytometer (Becton-Dickenson, Franklin Lakes, New Jersey, USA). We tested dried blood spots of household-members for HIV using a parallel enzyme immunoassay (EIA) screening algorithm [Genetic Systems rLAV EIA; Bio-Rad, Redmond, Washington, USA and Vironostika HIV-1 EIA; BioMerieux, Durham, North Carolina, USA or Vironostika HIV Uni-Form II plus O; BioMerieux, Boxtel, The Netherlands].
Data management and statistical analysis
We double-entered questionnaire data using Epi-Info 2002 (CDC, Atlanta, Georgia, USA) and conducted analysis using SAS version 9.1 (SAS Institute, Cary, North Carolina, USA). We included only adults who had their baseline data collected within 2 weeks of initiating ART. We excluded data from clients who were ARV-experienced at enrollment or who initially enrolled as household members because their ART exposure periods were different from index participants. We analyzed follow-up data collected between 150 and 210 days after initiating ART.
We compared baseline demographic and behavioral characteristics between men and women using chi-squared tests. To assess factors associated with being sexually active and changes in sexual activity over time we conducted participant-level analyses (unit of analysis was a participant initiating ART). We developed multivariate logistic regression models to assess predictors of being sexually active at baseline and to compare sexual activity at baseline with follow-up.
We also conducted sexual partner-level analyses (unit of analysis was a sexual partner of a participant initiating ART) incorporating into a model partner HIV-status, number of sexual contacts, condom use, and the cohort member's HIV viral load. Multiple partners of the same participant were included as separate units of analysis. The number of sexual acts and unprotected sexual acts per year were analyzed using Poisson regression models. In both the logistic and Poisson regression models, we used generalized estimating equation methods with an exchangeable correlation structure to adjust for repeated observations for the same cohort member.
HIV transmission risk
We calculated partner-specific transmission risks and summed these to assess overall transmission risk for the population. Expected sero-conversions in the last 3 months were calculated using number of partners, partner-specific condom use, partner HIV status, frequency of sexual behavior, and viral load. We conservatively calculated and used in our model a mean log viral load from the 3-month and 6-month viral loads of the participants. Probabilities of transmission per coital act based on viral load and age were derived from sero-conversion studies of HIV-discordant couples in Uganda [24,25]. For protected sexual acts, we conservatively applied a 20% condom failure rate.[26,27] We also estimated HIV transmission rates at baseline and follow-up using partner HIV-status based on baseline laboratory results, rather than participant report of their partner's HIV status. These analyses were restricted to cohabiting partners of participants for whom laboratory HIV results were available.
Participant characteristics and follow-up
A total of 926 ART-naive adults, from 905 households, were included in the baseline analysis. Of these, 40 (4%) died prior to follow-up and four (0.4%) did not complete a follow-up interview. For 882 persons who had follow-up interviews, the mean time interval from ART initiation to follow-up data collection was 185 days; 815 (93%) fell between 150 to 210 days and were included for follow-up analysis.
The median age at enrollment was 41 years for men and 37 years for women. The population had advanced HIV infection at baseline, with a mean CD4 cell count of 124 cells/μl and a median serum HIV-1 RNA level of 226 000 copies/ml. Women were less educated, less likely to drink alcohol, less likely to want more children and more likely to be widowed than men. Only 23% of participants had education beyond primary school (Table 1).
Sexual activity at baseline
At baseline, 53% of men and 79% of women reported abstinence in the previous 3 months. Of these, 34% had chosen to abstain, and 66% reported temporal reasons for abstinence including poor health, no partner, and no interest. Of the 318 living in stable relationships for whom sexual behavior information was available, 100 (65%) men and 96 (59%) women reported that they had had sexual intercourse in the past 3 months. Of the 605 not living with a regular partner, 13% of men and 9% of women reported sexual intercourse in the previous 3 months. Overall, 234 (92%) of those sexually active had had only one partner and 191 (75%) had had sex only with a spouse in the previous 3 months. There were 193 participants who had sex with spouses, 37 with steady partners, and 25 with casual partners. Among the sexually active, 44% of women and 45% of men reported unprotected sex with at least one partner.
In multivariate analysis, factors independently associated with sexual activity at baseline included age, marital status, main source of income, viral load and number of lifetime sexual partners. Sexual activity decreased with each increasing year of age [odds ratio (OR), 0.96; 95% confidence interval (CI), 0.93–0.98; P = 0.0005]. Those who were married or cohabiting were more likely to be sexually active compared with those who were widowed (OR, 23.4; 95% CI, 14.6–37.6; P < 0.0001). Participants whose main source of income was trade were more likely to be sexually active than farmers (OR, 2.4; 95% CI, 1.4–4.0; P = 0.0007). Participants with viral loads ≤ 38 500 copies/ml were more likely to be sexually active in comparison with those with viral load > 38 500 copies/ml (OR, 1.9; 95% CI, 1.1–3.4; P = 0.0242). Sexual activity was more common among persons with ≥ 5 lifetime partners (OR, 2.9; 95% CI, 1.7–5.1; P = 0.0002), or three or four lifetime sexual partners (OR, 2.0; 95% CI, 1.2–3.5; P = 0.0134) compared with those with < 3 lifetime sexual partners.
Sexual activity after 6 months on ART
The proportion of participants who had had sexual intercourse within the prior 3 months did not change between baseline and follow-up for either women (21 versus 24%, P = 0.1772) or men (47 versus 53%, P = 0.2243), but both reported changes in sexual feelings and experiences (Table 2). Consistent condom use increased and unprotected sex with partners of negative or unknown status decreased (Table 2).
Changes in risky sex within partnerships
At baseline 255 sexually active people had 280 partners; at follow-up 252 people had 268 partners. Partner-based analyses showed increases in consistent condom use from 59 to 82% (P = 0.0003) with partners with negative or unknown HIV status. The mean number of sexual contacts in the previous 3 months did not increase significantly (Table 3). Overall, there was a 70% reduction in the number of unprotected sexual acts with a partner of known negative or unknown sero-status: among men there was a 75% reduction (5.4 sex acts versus 1.3 sex acts; P = 0.0198), and among women, a 58% reduction (3.5 sex acts versus 1.5 sex acts; P = 0.0268). Condom use increased within concordant positive partnerships although the decline in mean number of unprotected sexual contacts was not significant (Table 3). Overall 88% of risky sexual acts at baseline and 86% at follow-up occurred within married and cohabiting couples.
HIV transmission risk within partnerships
After 6 months on ART, 85% of persons engaging in sex with negative or partners with unknown status had an HIV-1 RNA level below 1700 copies/ml (Table 4), the level associated with lowest risk in previous studies. [8,25] Estimated risk of HIV transmission to partners of negative and unknown status reduced from 45.7 per 1000 person years at baseline to 0.9 per 1000 person years at follow-up, representing a 98% decrease (Table 4). When analysis was restricted to the 49 cohabiting and sexually active partners for whom HIV-negative status based on study laboratory investigations was available, results were similar (risk of HIV transmission reduced from 43.5 per 1000 person years to 0.8 per 1000 person years, representing a 98% decrease). When VCT was repeated at 1 year for these HIV-negative spouses, one male spouse of a female index participant had sero-converted. Both spouses self-reported inconsistent condom use with each other and the man reported unprotected sex with an outside steady HIV-positive partner.
Providing ART, prevention counseling, and partner VCT reduced self-reported sexual risk behavior among HIV-infected adults in rural Uganda and also substantially reduced the risk of transmission to their uninfected partners. Overall, there was a 70% reduction in risky sex and a 98% reduction in the number of estimated sero-conversions after 6 months. Changes occurred among men and women, irrespective of age. These findings support arguments for incorporating prevention into ART programs  and provide initial empirical evidence that ART, when combined with prevention interventions, can help reduce HIV transmission in Africa.
Over 85% of risky sexual behavior at baseline and follow-up occurred within married and cohabiting couples. HIV discordance is common within couples in Africa, ranging from 3–20% in the general population [29–31] to as high as 51% within couples in which one partner seeks HIV care services [32,33], but knowledge of partner status and understanding of discordance is extremely low [21,34] To reduce the high risk of HIV transmission within discordant couples and to minimize primary infection with drug-resistant strains of HIV, ART programs in Africa should consider not only prevention counselling, but proactive testing of sexual partners.
Overall, sexual activity remained low in this population, with the majority still abstinent after 6 months on ART. While this may reflect our sample, which included a high proportion of older, widowed women, similar findings have been reported from Cote D'Ivoire . However, both men and women experienced substantial increases in sexual desire and in opportunities to meet new partners after ART initiation, highlighting the importance of on-going prevention interventions for populations on ART.
Without a randomized efficacy trial, it is not possible to disaggregate the effects of our prevention activities, which included making a personal sexual behavior plan, partner VCT, and condom provision from the effects of providing ART alone. However, ethical considerations would probably preclude such a trial, as similar prevention interventions in the pre-ART era involving HIV-infected people in Africa, such as VCT interventions for discordant couples, also resulted in substantial increases in reported condom use – from 3 to 80% in Zambia  and 5 to 71% in Congo . The interventions we used could be replicated by other ART programs and standards for incorporating prevention into ART programs in Africa would be beneficial. Evidence-based guidelines have already been developed elsewhere and could be rapidly adapted and disseminated in Africa .
Our findings are based on self-reported sexual behavior, which has been shown to be biased in some settings . A further limitation of our data could be that study counselors who provided on-going risk reduction counseling also interviewed participants. This may have led to under-reporting of risky sex by participants due to social desirability. However, counselors were trained to minimize bias by using non-judgmental approaches. Moreover, within the subset of discordant spouses for whom we had laboratory confirmed HIV results at 1 year, no sero-conversions occurred among those who reported consistent condom use. The one man who sero-converted had self-reported inconsistent condom use and multiple HIV-positive partners, thereby providing evidence that self-report may be reliable in this population. Given the expense of HIV incidence studies, nearly all studies on ART and sexual risk behavior have been based on self-reported data . Finally, large studies in Uganda have shown correlations between self-reported sexual behavior and HIV infection , suggesting that biases introduced by use of self-reported data in Uganda do not mask key associations.
We assumed conservatively that all partners of unknown status were HIV-negative and that condom failure rates were 20%; however, if some of these partners were HIV-positive or condom failure rates were lower, then we may have overestimated overall transmission risk. Our findings of equivalent transmission risk estimates among the subset with laboratory confirmed HIV status suggested that little bias was introduced because of partners of unknown HIV status. As we used established transmission rates from a population that did not contain persons with undetectable viral loads, we may have also differentially overestimated transmission risk at follow-up by assigning the same transmission risk to those with undetectable viral loads as to those with viral load < 1700 copies/ml. Finally, on-going monitoring, beyond our 6-month follow-up, will be important to assess whether the reductions in risky sex and HIV transmission risk are maintained over time. Risk behavior monitoring and prevention interventions targeting HIV-negative people as well as HIV-infected persons not on ART will also be critical as access to ART expands in Africa.
Our findings support arguments that integrated ART and prevention programs can reduce HIV incidence among uninfected sexual partners of persons on therapy in Africa. Minimizing HIV transmission by persons taking ART will also help to minimize primary infections with drug-resistant strains of HIV and help to extend the utility of less expensive first-line regimens in Africa. Randomized efficacy evaluations of simple prevention interventions that can be implemented in ART clinical settings are needed. Given the extremely high cost of ART, even for generic formulations, the added investment by ART programs for a strong prevention component would be marginal while the potential gains in reducing HIV transmission could be substantial. Our findings that an integrated ART and prevention program may reduce HIV transmission risk reinforce clinical and equity arguments for expanding ART to the millions of Africans who will soon die without it.
We thank HBAC project staff and clients for all their time and efforts. Dr. Robert Downing supervised all laboratory work for HBAC and R Ransom, S Bechange and S Moss assisted with data management. We also thank Drs W McFarland, K Lindan, R Stall, D Purcell, and J Moore for their comments on earlier versions of this manuscript and T Wamala for her assistance with the references.
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Journal of Behavioral MedicineHIV treatment beliefs and sexual transmission risk behaviors among HIV positive men and womenJournal of Behavioral Medicine
Access to adequate nutrition is a major potential obstacle to antiretroviral adherence among HIV-infected individuals in Rwanda
AIDS Patient Care and StdsPrevalence and determinants of fertility intentions of HIV-infected women and men receiving antiretroviral therapy in South AfricaAIDS Patient Care and Stds
Cross-sectional research design and relatively low HIV incidence, rather than blood exposures, explain the peripheral location of HIV cases within the sexual networks observed on Likoma
AIDS Care-Psychological and Socio-Medical Aspects of AIDS/HivWomen, economic hardship and the path of survival: HIV/AIDS risk behavior among women receiving HIV/AIDS treatment in UgandaAIDS Care-Psychological and Socio-Medical Aspects of AIDS/Hiv
AIDS and BehaviorAntiretroviral Therapy is Associated with Increased Fertility Desire, but not Pregnancy or Live Birth, among HIV plus Women in an Early HIV Treatment Program in Rural UgandaAIDS and Behavior
Clinical Infectious DiseasesTreatment to Prevent Transmission of HIV-1Clinical Infectious Diseases
Clinical Infectious DiseasesPrevention of Tuberculosis in People Living with HIVClinical Infectious Diseases
Plos OneReproductive Intentions and Outcomes among Women on Antiretroviral Therapy in Rural Uganda: A Prospective Cohort StudyPlos One
Plos OneSexually Transmitted Infections among HIV-1-Discordant CouplesPlos One
AIDS Care-Psychological and Socio-Medical Aspects of AIDS/HivThe relationship between HAART use and sexual activity among HIV-positive women of reproductive age in Brazil, South Africa, and UgandaAIDS Care-Psychological and Socio-Medical Aspects of AIDS/Hiv
International Journal of Tuberculosis and Lung Disease
Provider-initiated HIV testing and counselling for TB patients and suspects in Nairobi, Kenya
International Journal of Tuberculosis and Lung Disease, 12(3):
LancetHeterosexual HIV-1 transmission after initiation of antiretroviral therapy: a prospective cohort analysisLancet
LancetAdherence to antiretroviral therapy in a home-based AIDS care programme in rural UgandaLancet
Reproductive Health Matters
Integrated antiretroviral and prevention programmes helps to reduce HIV transmission in Uganda
Reproductive Health Matters, 14():
Southern African Journal of Hiv Medicine
Positive prevention: HFV transmission risk reduction-4 interventions for people living with HIV/AIDS
Southern African Journal of Hiv Medicine, ():
AIDS Patient Care and StdsSafer sexual behaviors after 12 months of antiretroviral treatment in Mombasa, Kenya: A prospective cohortAIDS Patient Care and Stds
Social Science & MedicineThe virus stops with me: HIV-infected Ugandans' motivations in preventing HIV transmissionSocial Science & Medicine
Hiv MedicineRisk factors for HIV transmission among heterosexual discordant couples in South IndiaHiv Medicine
Jama-Journal of the American Medical Association
HIV prevention for a threatened continent - Implementing positive prevention in Africa
Jama-Journal of the American Medical Association, 296(7):
Sexually Transmitted InfectionsRecent multiple sexual partners and HIV transmission risks among people living with HIV/AIDS in BotswanaSexually Transmitted Infections
Clinical Infectious DiseasesPreventing sexual transmission of HIVClinical Infectious Diseases
Bundesgesundheitsblatt-Gesundheitsforschung-GesundheitsschutzPrevention strategies to control the HIV epidemic. Successes, problems, and perspectivesBundesgesundheitsblatt-Gesundheitsforschung-Gesundheitsschutz
AIDS and BehaviorChanges in Risk Behavior Among HIV-Positive Patients During Their First Year of Antiretroviral Therapy in Cape Town South AfricaAIDS and Behavior
The World Health Organization's global strategy for prevention and assessment of HIV drug resistance
Antiviral Therapy, 13():
Recommendations for surveillance of transmitted HIV drug resistance in countries scaling up antiretroviral treatment
Antiviral Therapy, 13():
Plos OneAssociation of Attitudes and Beliefs towards Antiretroviral Therapy with HIV-Seroprevalence in the General Population of Kisumu, KenyaPlos One
Sexually Transmitted InfectionsPrevalence of unsafe sex with one's steady partner either HIV-negative or of unknown HIV status and associated determinants in Cameroon (EVAL ANRS12-116 survey)Sexually Transmitted Infections
AIDS and BehaviorDepression and CD4 cell count among persons with HIV infection in UgandaAIDS and Behavior
Evaluating the impact of antiretroviral therapy on HIV transmission
Social aspects of antiretroviral therapy scale-up: introduction and overview
Gender, sexuality, and antiretroviral therapy: using social science to enhance outcomes and inform secondary prevention strategies
Journal of Clinical InvestigationThe spread, treatment, and prevention of HIV-1: evolution of a global pandemicJournal of Clinical Investigation
Revista Da Associacao Medica Brasileira
Hiv in Middle-Aged Women: Associated Factors
Revista Da Associacao Medica Brasileira, 56(1):
Sexually Transmitted InfectionsDisclosure of HIV status to sex partners and sexual risk behaviours among HIV-positive men and women, Cape Town, South AfricaSexually Transmitted Infections
Plos MedicineCircumcision for HIV prevention: Authors' replyPlos Medicine
Journal of Infectious DiseasesExpanded access to highly active antiretroviral therapy: A potentially powerful strategy to curb the growth of the HIV epidemicJournal of Infectious Diseases
Sexually Transmitted InfectionsIndicators for sexual HIV transmission risk among people in Thailand attending HIV care: the importance of positive preventionSexually Transmitted Infections
Future VirologyEarly events in vaginal HIV transmission: implications in microbicide developmentFuture Virology
AIDS Care-Psychological and Socio-Medical Aspects of AIDS/HivThe role of HIV testing, counselling, and treatment in coping with HIV/AIDS in Uganda: a qualitative analysisAIDS Care-Psychological and Socio-Medical Aspects of AIDS/Hiv
European Journal of Public HealthHIV transmission risk behaviours among HIV seropositive sexually transmitted infection clinic patients in Cape Town, South AfricaEuropean Journal of Public Health
Cochrane Database of Systematic ReviewsHome-based HIV voluntary counseling and testing in developing countriesCochrane Database of Systematic Reviews
Plos OneThe Impact of Pre-Exposure Prophylaxis (PrEP) on HIV Epidemics in Africa and India: A Simulation StudyPlos One
Universal voluntary HIV testing and immediate antiretroviral therapy
AIDS Care-Psychological and Socio-Medical Aspects of AIDS/HivModeling HIV transmission risk among Mozambicans prior to their initiating highly active antiretroviral therapyAIDS Care-Psychological and Socio-Medical Aspects of AIDS/Hiv
American Journal of Public HealthThe utilization of testing and counseling for HIV: A review of the social and behavioral evidenceAmerican Journal of Public Health
International Journal of Std & AIDSSexual risk behaviour and HAART: a comparative study of HIV-infected persons on HAART and on preventive therapy in KenyaInternational Journal of Std & AIDS
Sexually Transmitted InfectionsLongitudinal effect following initiation of highly active antiretroviral therapy on plasma and cervico-vaginal HIV-1 RNA among women in Burkina FasoSexually Transmitted Infections
Bmc Public HealthVoluntary HIV counselling and testing among men in rural western Uganda: Implications for HIV preventionBmc Public Health
Culture Health & SexualitySex after ART: sexual partnerships established by HIV-infected persons taking anti-retroviral therapy in Eastern UgandaCulture Health & Sexuality
Sexual HealthSafer sexual behaviours after 1 year of antiretroviral treatment in KwaZulu-Natal, South Africa: a prospective cohort studySexual Health
HIV testing in patients with TB
Tropical Doctor, 36(2):
NatureAIDS treatment: Staying the courseNature
HIV-1 acquisition and disease progression are associated with decreased high-risk sexual behaviour among Kenyan female sex workers
The use of routine monitoring and evaluation systems to assess a referral model of family planning and HIV service integration in Nigeria
Culture Health & SexualityChanges in sexual risk taking with antiretroviral treatment: influence of context and gender norms in Mombasa, KenyaCulture Health & Sexuality
Annals of Internal Medicine
Narrative review: Antiretroviral therapy to prevent the sexual transmission of HIV-1
Annals of Internal Medicine, 146(8):
AIDS Care-Psychological and Socio-Medical Aspects of AIDS/HivThe impact of HIV treatment on risk behaviour in developing countries: A systematic reviewAIDS Care-Psychological and Socio-Medical Aspects of AIDS/Hiv
Sexually Transmitted InfectionsA systematic review of published evidence on intervention impact on condom use in sub-Saharan Africa and AsiaSexually Transmitted Infections
Jaids-Journal of Acquired Immune Deficiency Syndromes
Mathematical models for HIV transmission dynamics - Tools for social and behavioral science research
Jaids-Journal of Acquired Immune Deficiency Syndromes, 47():
Bmc MedicineWhen to start antiretroviral therapy: as soon as possibleBmc Medicine
AIDS Research and TherapySexual behavior of HIV-positive adults not accessing HIV treatment in Mombasa, Kenya: Defining their prevention needsAIDS Research and Therapy
AIDS Research and TherapyIs the Sexual Behaviour of HIV Patients on Antiretroviral therapy safe or risky in Sub-Saharan Africa? Meta-Analysis and Meta-RegressionAIDS Research and Therapy
Janac-Journal of the Association of Nurses in AIDS CareAn Integrated Approach for Antiretroviral Adherence and Secondary HIV Transmission Risk-Reduction Support by Nurses in KenyaJanac-Journal of the Association of Nurses in AIDS Care
Quality of Life ResearchMeasuring quality of life in rural Uganda: reliability and validity of summary scores from the Medical Outcomes Study HIV Health Survey (MOS-HIV)Quality of Life Research
AIDS Research and TherapySexual risk behaviour, marriage and ART: a study of HIV-positive people in Papua New GuineaAIDS Research and Therapy
AIDS Care-Psychological and Socio-Medical Aspects of AIDS/HivChanges in sexual activity and risk behaviors among PLWHA initiating ART in rural district hospitals in Cameroon Data from the STRATALL ANRS 12110/ESTHER trialAIDS Care-Psychological and Socio-Medical Aspects of AIDS/Hiv
AIDS Care-Psychological and Socio-Medical Aspects of AIDS/HivHIV treatment optimism and its predictors among young adults in southern MalawiAIDS Care-Psychological and Socio-Medical Aspects of AIDS/Hiv
Bmc Public HealthNondisclosure prosecutions and population health outcomes: examining HIV testing, HIV diagnoses, and the attitudes of men who have sex with men following nondisclosure prosecution media releases in Ottawa, CanadaBmc Public Health
Journal of Sexual MedicineImpaired Masturbation-Induced Erections: A New Cardiovascular Risk Factor for Male Subjects with Sexual DysfunctionJournal of Sexual Medicine
American Journal of Preventive MedicineBrief Risk-Reduction Counseling in Clinical Settings for HIV Pre-Exposure ProphylaxisAmerican Journal of Preventive Medicine
Bmj OpenDoes antiretroviral therapy initiation increase sexual risk taking in Kenyan female sex workers? A retrospective case-control studyBmj Open
AIDS and BehaviorUnsafe Sex and STI Prevalence Among HIV-Infected Adults in Guangzhou, China: Opportunities to Deamplify Sexual HIV TransmissionAIDS and Behavior
Journal of the International AIDS SocietySexual risk after HIV diagnosis: a comparison of pre-ART individuals with CD4 > 500 cells/mu l and ART-eligible individuals in a HIV treatment and care programme in rural KwaZulu-Natal, South AfricaJournal of the International AIDS Society
Plos OneChanging Risk Behaviours and the HIV Epidemic: A Mathematical Analysis in the Context of Treatment as PreventionPlos One
Critical Public HealthSexual practices and STI/HIV testing among gay, bisexual, and men who have sex with men in Ottawa, Canada: examining nondisclosure prosecutions and HIV preventionCritical Public Health
AIDS Patient Care and StdsDisclosure, Knowledge of Partner Status, and Condom Use Among HIV-Positive Patients Attending Clinical Care in Tanzania, Kenya, and NamibiaAIDS Patient Care and Stds
Nigerian Journal of Clinical PracticeCharacteristics of clients accessing HIV counseling and testing services in a tertiary hospital in Sagamu, Southwestern NigeriaNigerian Journal of Clinical Practice
Plos OneHIV-1 Transmission during Early Antiretroviral Therapy: Evaluation of Two HIV-1 Transmission Events in the HPTN 052 Prevention StudyPlos One
Bmc Public HealthAlcohol use and HIV serostatus of partner predict high-risk sexual behavior among patients receiving antiretroviral therapy in South Western UgandaBmc Public Health
Plos OneUnderstanding the Potential Impact of a Combination HIV Prevention Intervention in a Hyper-Endemic CommunityPlos One
GLOBAL HEALTH Persuasive evidence on HIV policy
Plos OneEstimating the Impact of State Budget Cuts and Redirection of Prevention Resources on the HIV Epidemic in 59 California Local Health DepartmentsPlos One
Ajar-African Journal of AIDS ResearchPoor-quality health services and lack of programme support leads to low uptake of HIV testing in rural MozambiqueAjar-African Journal of AIDS Research
Current Opinion in Hiv and AIDSFifteen million people on antiretroviral treatment by 2015: treatment as preventionCurrent Opinion in Hiv and AIDS
Plos OneDisinhibition in Risky Sexual Behavior in Men, but Not Women, during Four Years of Antiretroviral Therapy in Rural, Southwestern UgandaPlos One
Plos OneEducational Intervention Increased Referrals to Allopathic Care by Traditional Healers in Three High HIV-Prevalence Rural Districts in MozambiquePlos One
JAIDS Journal of Acquired Immune Deficiency SyndromesHome-Based Antiretroviral Care Is Associated With Positive Social Outcomes in a Prospective Cohort in UgandaJAIDS Journal of Acquired Immune Deficiency Syndromes
JAIDS Journal of Acquired Immune Deficiency SyndromesSexual Behavior and Reproductive Health Among HIV-Infected Patients in Urban and Rural South AfricaJAIDS Journal of Acquired Immune Deficiency Syndromes
JAIDS Journal of Acquired Immune Deficiency SyndromesIncreasing Uptake of HIV Testing and Counseling Among the Poorest in Sub-Saharan Countries Through Home-Based Service ProvisionJAIDS Journal of Acquired Immune Deficiency Syndromes
JAIDS Journal of Acquired Immune Deficiency SyndromesCharacteristics of HIV Voluntary Counseling and Testing Clients Before and During Care and Treatment Scale-Up in Moshi, TanzaniaJAIDS Journal of Acquired Immune Deficiency Syndromes
Africa; antiretroviral therapy; prevention of sexual transmission; sexual behaviour; viral load; epidemiology; Uganda
© 2006 Lippincott Williams & Wilkins, Inc.
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