Repeat voluntary HIV counseling and testing (VCT), sexual risk behavior and HIV incidence in Rakai, Uganda

We examined the effects of repeat Voluntary HIV counseling and testing (VCT) on sexual risk behaviors and HIV incidence in 6,377 initially HIV-negative subjects enrolled in a prospective STD control for HIV prevention trial in rural Rakai district, southwestern Uganda. Sixty-four percent accepted VCT, and of these, 62.2% were first time acceptors while 37.8% were repeat acceptors. Consistent condom use was 5.8% in repeat acceptors, 6.1% in first time acceptors and 5.1% in non-acceptors. A higher proportion of repeat acceptors (15.9%) reported inconsistent condom use compared to first-time acceptors (12%) and non-acceptors (11.7%). Also, a higher proportion of repeat acceptors (18.1%) reported 2+ sexual partners compared to first-time acceptors (14.1%) and non-acceptors (15%). HIV incidence rates were 1.4/100 py (person-years) in repeat acceptors, 1.6/100 py in first time acceptors and 1.6/100 py in non-acceptors. These data suggest a need for intensive risk-reduction counseling interventions targeting HIV-negative repeat VCT acceptors as a special risk group.

Assessing country-level efforts to link research to action

We developed a framework for assessing country-level efforts to link research to action. The framework has four elements. The first element assesses the general climate (how those who fund research, universities, researchers and users of research support or place value on efforts to link research to action). The second element addresses the production of research (how priority setting ensures that users' needs are identified and how scoping reviews, systematic reviews and single studies are undertaken to address these needs). The third element addresses the mix of four clusters of activities used to link research to action. These include push efforts (how strategies are used to support action based on the messages arising from research), efforts to facilitate "user pull" (how "one-stop shopping" is provided for optimally packaged high-quality reviews either alone or as part of a national electronic library for health, how these reviews are profiled during "teachable moments" such as intense media coverage, and how rapid-response units meet users' needs for the best research), "user pull" efforts undertaken by those who use research (how users assess their capacity to use research and how structures and processes are changed to support the use of research) and exchange efforts (how meaningful partnerships between researchers and users help them to jointly ask and answer relevant questions). The fourth element addresses approaches to evaluation (how support is provided for rigorous evaluations of efforts to link research to action).

Clinical illness as a marker for initiation of HIV antiretroviral therapy in a rural setting, Rakai, Uganda

The aim of this study is to assess whether HIV-related illness and World Health Organization (WHO) clinical stage can be used to guide initiation of antiretroviral therapy (ART) in rural Rakai District, Uganda. A retrospective cohort analysis of 910 HIV-seroprevalent individuals randomly sampled from a community cohort was conducted. The associations between HIV-related clinical illness and HIV viral loads >55,000 copies/mL and death were evaluated as a guide for initiation of ART. Reporting one or more HIV-related illnesses was associated with high specificity for identifying HIV viral load >55,000 copies/mL and predicting death within 30 months. There were more deaths in those with one symptom at baseline (16.3%) and two or more symptoms (25.0%) than in those reporting no symptoms (9.6%; P = 0.001).HIV-related illness and WHO stage predicted disease progression. The specificity of clinical illness to predict viral load >55,000 copies/mL was high and could be used to rule in HIV disease requiring ART.

Screening HIV-positive pregnant women for antiretroviral therapy: utility of self-reported symptoms

In developing countries, Mother-to-Child Transmission-Plus programmes propose to identify lifelong antiretroviral therapy (ART)-eligible women during antenatal care. Identification using AIDS-related symptoms is the most feasible screening procedure in resource-limited settings. It is not known if symptomatology in pregnant women is correlated with clinical criteria for ART initiation based on CD(4)+ cell count or HIV-1 viral load. In this population of HIV-positive pregnant women from Rakai District, Uganda, 8-23% were eligible for treatment by CD(4)+ cell count criteria, and <1% met WHO staging criteria for AIDS. Using one or more symptoms to predict CD(4)+ cell count <350 cells/mm(3), sensitivity was 100%, specificity 11%, positive predictive value (PPV) 25%, and negative predictive value (NPV) 100%. When using one or more symptoms to predict viral load > or =100,000 cps/mL, sensitivity was 100%, specificity 10%, PPV 6%, and NPV 100%. Initiation of treatment based on self-reported symptoms will over-treat because the majority of pregnant women with symptoms would not be eligible for treatment under current guidelines, but asymptomatic pregnant women are unlikely to require ART.

Disclosure of HIV Status on Informed Consent Forms Presents an Ethical Dilemma for Protection of Human Subjects

The privacy of copies of consent forms provided to research participants cannot be guaranteed. Therefore, consent forms that disclose a subject's HIV status may result in breach of confidentiality and cause social harms. Under the ethical principle of beneficence defined in the Belmont Report, we recommend that disclosure of HIV status be through voluntary counseling and testing; however, whenever possible, copies of consent form should not specify HIV status.

Can population differences explain the contrasting results of the Mwanza, Rakai, and Masaka HIV/sexually transmitted disease intervention trials?: A modeling study

OBJECTIVE

To determine whether population differences can explain the contrasting impacts on HIV observed in the Mwanza trial of sexually transmitted disease (STD) syndromic treatment (ST), the Rakai trial of STD mass treatment (MT), and the Masaka trial of information, education, and communication (IEC) with and without ST as well as to predict the effectiveness of each intervention strategy in each population.

METHODS

Stochastic modeling of the transmission of HIV and 6 STDs was used with parameters fitted to demographic, sexual behavior, and epidemiological data from the trials and general review of STD/HIV biology.

RESULTS

The baseline trial populations could be simulated by assuming higher risk behavior in Uganda compared with Mwanza in the 1980s, followed by reductions in risk behavior in Uganda preceding the trials. In line with trial observations, the projected HIV impacts were larger for the ST intervention in Mwanza than for the MT intervention in Rakai or the IEC and IEC + ST interventions in Masaka. All 4 simulated intervention strategies were more effective in reducing incidence of HIV infection in Mwanza than in either Rakai or Masaka.

CONCLUSIONS

Population differences in sexual behavior, curable STD rates, and HIV epidemic stage can explain most of the contrast in HIV impact observed between the 3 trials. This study supports the hypothesis that STD management is an effective HIV prevention strategy in populations with a high prevalence of curable STDs, particularly in an early HIV epidemic.

The incidence and prevalence of orphanhood associated with parental HIV infection: a population-based study in Rakai, Uganda

BACKGROUND

There are limited empirical data on the prevalence and incidence of orphanhood due to parental HIV infection.

OBJECTIVE

To assess the prevalence and incidence of orphanhood, and the population attributable fraction (PAF) of incident orphanhood associated with parental HIV infection, in a rural population with a 14.8% adult HIV prevalence.

METHODS

The data are derived from a community cohort in Rakai District, Uganda. Census data were collected on all resident members in 10,657 households, including survival of parents of resident children in 1996/1997. Consenting adults were interviewed, provided blood for HIV testing, and were followed up 10 months later to determine parental death and incident orphanhood. The incidence rate ratio (IRR) of orphanhood associated with parental HIV-infection was estimated by Poisson multivariate regression.

RESULTS

A total of 22,712 children aged 0-14 years were enumerated in 1996/1997. The overall prevalence of orphanhood was higher among children of HIV-infected parents (22.7%) compared with children of uninfected parents, 7.9%. The annual incidence of orphanhood was 8.2% if at least one parent was HIV positive, and 0.5% if both parents were HIV negative (adjusted IRR = 18.93). Older age of children, and older maternal age were significantly associated with an increased risk of orphanhood. The PAF of incident orphanhood due to parental HIV infection was 37.3%, and was highest among younger children (adjusted PAF = 50.6% for 0-4 year olds), and children with younger mothers aged < 25 years (adjusted PAF = 75.7%).

CONCLUSIONS

Parental HIV infection markedly increased the incidence of orphanhood, especially among younger children and the children of younger mothers.

Knowledge about vaccines and willingness to participate in preventive HIV vaccine trials: a population-based study, Rakai, Uganda

The purpose of the study was to assess knowledge and beliefs regarding vaccines and willingness to participate in HIV vaccine trials. A baseline survey assessed knowledge and attitudes toward vaccination and potential HIV vaccines among 14,177 participants aged 15-49 years, in a population cohort. Willingness to participate in HIV-preventive vaccine trials was assessed during a follow-up survey 10 months later after providing community education on HIV vaccines. Knowledge of the preventive utility of vaccines was high (71%), but higher in men than women (P<0.001), and increased with education levels (P<0.001). Vaccines were considered appropriate for children and women (99 and 88%, respectively), but not for adult men (28%). Participants felt that adolescents were the most appropriate subjects for HIV preventive vaccine trials (93.7%) but also thought that HIV-positive persons were eligible for trials (60.2%), and only 20% thought a preventive vaccine could help control HIV. HIV vaccine awareness increased from 68% at baseline to 81% at follow-up (P<0.001). Willingness to participate in HIV-preventive vaccine trials was 77%. Vaccine knowledge and willingness to participate in trials are high in this population. However, there still is need for education on the potential role of preventive HIV vaccines in the control of the epidemic and the importance of vaccination for men, especially in the context of an HIV vaccine.

Maternal self-medication and provision of nevirapine to newborns by women in Rakai, Uganda

To assess the effectiveness of maternal self-administration of nevirapine for prevention of mother-to-child transmission (MTCT) of HIV, we conducted a program to provide maternal and newborn doses of nevirapine to pregnant women in rural Uganda. Women provided blood for HIV testing and were offered voluntary counseling and testing (VCT) during annual community HIV surveys. HIV-positive women who accepted VCT were offered nevirapine tablets and syrup. Blood samples were collected postpartum from women and their babies. Infants were tested for HIV by polymerase chain reaction (PCR), and a subsample of maternal and infant blood was assayed for nevirapine. Among the 981 women tested for HIV, 900 (91.7%) accepted VCT, of whom 105 (11.7%) were HIV-positive. Ninety-three women accepted nevirapine, of whom 81 (87.1%) were followed postpartum; 75 (92.6%) reported receipt of the drug, and 69 reported taking the tablets (85.2%). There were 81 liveborn babies (3 sets of twins), and 67 (84.8%) received the syrup. In a subsample of 25 mothers reporting receipt of the drug, nevirapine was detected in 22 (88.0%) and 24 (96.0%) babies tested. PCR of 67 infant blood samples identified 5 HIV-positive (MTCT rate = 7.5%, 95% confidence interval [CI]: 0.3%-16.6%). Mothers can administer nevirapine to themselves and their newborns and can achieve low rates of perinatal HIV infection.

Rates of HIV-1 transmission per coital act, by stage of HIV-1 infection, in Rakai, Uganda

BACKGROUND

We estimated rates of human immunodeficiency virus (HIV)-1 transmission per coital act in HIV-discordant couples by stage of infection in the index partner.

METHODS

We retrospectively identified 235 monogamous, HIV-discordant couples in a Ugandan population-based cohort. HIV transmission within pairs was confirmed by sequence analysis. Rates of transmission per coital act were estimated by the index partner's stage of infection (recent seroconversion or prevalent or late-stage infection). The adjusted rate ratio of transmission per coital act was estimated by multivariate Poisson regression.

RESULTS

The average rate of HIV transmission was 0.0082/coital act (95% confidence interval [CI], 0.0039-0.0150) within approximately 2.5 months after seroconversion of the index partner; 0.0015/coital act within 6-15 months after seroconversion of the index partner (95% CI, 0.0002-0.0055); 0.0007/coital act (95% CI, 0.0005-0.0010) among HIV-prevalent index partners; and 0.0028/coital act (95% CI, 0.0015-0.0041) 6-25 months before the death of the index partner. In adjusted models, early- and late-stage infection, higher HIV load, genital ulcer disease, and younger age of the index partner were significantly associated with higher rates of transmission.

CONCLUSIONS

The rate of HIV transmission per coital act was highest during early-stage infection. This has implications for HIV prevention and for projecting the effects of antiretroviral treatment on HIV transmission.

Voluntary HIV counseling and testing acceptance, sexual risk behavior and HIV incidence in Rakai, Uganda

OBJECTIVE

To assess the acceptance of voluntary HIV counseling and testing (VCT) and the effects of VCT on sexual risk behavior and HIV acquisition in Rakai, Uganda.

METHODS

In a rural cohort, 10 694 consenting adults were interviewed, provided blood for HIV testing and were offered free VCT by community resident counselors. The proportions receiving VCT and the adjusted risk ratio (adj. RR) of VCT acceptance were estimated by log binomial regression. Risk behaviors and HIV incidence per 100 person-years (PY) in HIV-negative acceptors and non-acceptors of VCT were assessed prospectively.

RESULTS

Although 93% initially requested HIV results, 62.2% subsequently accepted VCT. VCT acceptance was lower among persons with no prior VCT [Adj. RR = 0.88; 95% confidence interval (CI), 0.85-0.90], individuals with primary education (adj. RR = 0.94; 95% CI, 0.90-0.99) or higher (adj. RR = 0.91; 95% CI, 0.87-0.97), individuals who were HIV-positive (adj. RR = 0.72; 95% CI, 0.68-0.76), and persons reporting condom use in the past 6 months (inconsistent users, adj. RR = 0.95; 95% CI, 0.90-0.99; consistent users, adj. RR = 0.88; 95% CI, 0.82-0.95). VCT acceptance was higher among the currently married (adj. RR = 1.14; 95% CI, 1.08-1.20) and previously married (adj. RR = 1.11; 95% CI, 1.04-1.18). Receipt of results was not significantly associated with age, gender, and self-perception of HIV risk. There were no significant differences in sexual risk behaviors, or in HIV incidence between acceptors (1.6/100 PY) and non-acceptors (1.4/100 PY) of VCT.

CONCLUSION

In this rural cohort where VCT services are free and accessible, there is self-selection of individuals accepting VCT, and no impact of VCT on subsequent risk behaviors or HIV incidence.

Effectiveness of syphilis treatment using azithromycin and/or benzathine penicillin in Rakai, Uganda

OBJECTIVE

The goal of this study was to assess azithromycin and/or benzathine penicillin for treatment of syphilis.

METHODS

In a population-based study, participants with serologic syphilis (TRUST with TPHA confirmation) were offered 2.4 MU benzathine penicillin intramuscularly. Intervention arm participants received 1 g presumptive oral azithromycin. We assessed cure rates with penicillin or azithromycin given alone and in combination. Cure assessed after 10 months was defined as seroreversion or a 4-fold decrease in titer. The rate ratio (RR) of cure and 95% confidence intervals (95% CIs) were estimated by log binomial regression.

RESULTS

Among 952 cases with syphilis, 18% received penicillin alone, 17% azithromycin only, and 65% dual treatment. The overall cure rate was 61%. Cure rates were lower in males compared with females (RR, 0.89; 95% CI, 0.80-0.99) and in subjects with initial titers > or =1:4 compared with < or =1:2 (RR, 0.77; 95% CI, 0.69-0.86). There was no significant differences in cure rates among HIV-positive and HIV-negative persons. With initial titers < or =1:2, there were no differences in cure rates by treatment regimen. However, with initial titers > or =1:4, significantly higher cure rates were observed with azithromycin alone (adjusted RR, 1.38; 95% CI, 0.97-1.96), and with dual treatment of azithromycin and benzathine penicillin (RR, 1.38; 95% CI, 1.03-1.87) compared with penicillin alone.

CONCLUSION

Azithromycin alone or in combination with penicillin achieved higher cure rates than penicillin alone in cases with a high initial TRUST titer. In low-titer infections, the 3 drug combinations were equally effective. HIV status did not affect cure rates.

Determinants of HIV‐1 Load in Subjects with Early and Later HIV Infections, in a General‐Population Cohort of Rakai, Uganda

Human immunodeficiency virus (HIV) type 1 RNA loads were determined for 256 subjects with early (incident) HIV infection and for 1293 subjects with later (prevalent) HIV infection, in a Ugandan cohort. Prevalent infections were classified as latent (0-1 symptoms) and midstage disease (>/=2 symptoms), and deaths were ascribed to acquired immunodeficiency syndrome. Among subjects with incident HIV infection, HIV load did not differ by sex, but, among subjects with prevalent HIV infection, it was higher in males than in females. HIV load was highest in subjects (25-29 years old) with incident HIV infection but increased with age in subjects with prevalent HIV infection. Viremia was higher after serconversion than in latency and increased with more advanced disease. Viremia was increased with genital ulcer disease (GUD) in both subjects with incident infection and in those with prevalent infection, and with herpes simplex virus type 2 seropositivity in subjects with incident HIV infection. GUD was consistently associated with higher HIV loads in subjects with incident and those with prevalent HIV infection, suggesting that treatment of GUD might reduce HIV viremia.

Burden of infection among heads and non-head of rural households in Rakai, Uganda

The objective was to determine HIV prevalence, symptomatology and mortality among adult heads and non-heads of households, in order to assess the burden of HIV on households. It was a community study of 11,536 adults aged 15-59, residing in 4,962 households in 56 villages, Rakai district, Uganda. First, 4,962 heads and 6,574 non-heads of households were identified from censuses. Interviews were then used to determine socio-demographic/behavioural characteristics. HIV seroprevalence was diagnosed by two EIAs with Western blot confirmation. The adjusted odds ratio (OR) and 95% confidence intervals (CI) of HIV infection in household heads and non-heads were estimated by multivariate logistic regression. Age-adjusted mortality was also assessed. HIV prevalence was 16.9% in the population, and 21.5% of households had at least one HIV-infected person (<0.0001). HIV prevalence was higher among heads than non-heads of households (21.5 and 13.3%, respectively, OR=1.79; CI 1.62-1.97). Most household heads were males (70.5%), and HIV prevalence was 17.8% among male heads compared with 6.6% in male non-heads of households (OR=2.31; CI 1.65-2.52). Women heading households were predominantly widowed, separated or divorced (64.4%). HIV prevalence was 30.5% among female heads, compared with 15.6% in female non-household heads (OR=1.42; CI 1.15-1.63). Age-adjusted mortality was significantly lower among male household heads than non-heads, both for the HIV-positive (RR=0.68) and HIV-negative men (RR=0.63). Among women, HIV-negative female household heads had significantly higher mortality than HIV-uninfected female non-heads (RR=1.72). HIV disproportionately affects heads of households, particularly males. Mortality due to AIDS is likely to increase the proportion of female-headed households, and adversely affect the welfare of domestic units.

The incidence of HIV-1 associated with injections and transfusions in a prospective cohort, Rakai, Uganda

The incidence of HIV associated with medical injections was assessed in a cohort of 6868 HIV-negative individuals; 42.8% reported injections and 0.5% reported transfusions. The Poisson adjusted rate ratios and 95% confidence intervals (CI) of incident HIV were 1.05% (CI 0.75-1.46) associated with medical injections, and 3.92 (CI 1.22-12.58) associated with transfusions. Sexual behaviours were significantly associated with HIV risk. Medical injections did not increase HIV acquisition in this rural Ugandan population.

Higher risk behaviour and rates of sexually transmitted diseases in Mwanza compared to Uganda may help explain HIV prevention trial outcomes

OBJECTIVE

To determine to what extent the higher impact of treatment for sexually transmitted diseases (STD) on HIV incidence in Mwanza, Tanzania than in Rakai and Masaka, Uganda might be explained by baseline differences between the trial populations.

DESIGN

A re-analysis of baseline data from the three trial populations comparing demography, sexual risk behaviour and HIV/STD epidemiology.

METHODS

Data were compared after age-standardization and adjustments for sample selection where necessary. STD rates were also adjusted for the sensitivities and specificities of the diagnostic techniques used.

RESULTS

Demographic patterns were similar across populations, apart from effects of AIDS on fertility and mortality (including widowhood) in Uganda. Higher sexual risk behaviours, including younger age of sexual debut, higher numbers of recent partners and lower frequency of condom use, were apparent in Mwanza compared to Masaka and Rakai. High-titre serological syphilis, gonorrhoea, chlamydia infection and trichomoniasis were all more prevalent in Mwanza, except for chlamydia infection in males. There was little difference between sites in the seroprevalence of Herpes simplex virus type-2. Age patterns in the prevalence of short-duration STD and current risk behaviours were similar across sites but all-titre serological syphilis was more prevalent among older participants in Rakai and Masaka than Mwanza.

CONCLUSIONS

Differences between trial populations included higher reported risk behaviour and higher rates of curable STD in Mwanza compared to Rakai and Masaka. These differences probably relate to previous reductions in risk behaviour in Uganda and may explain, at least in part, the contrasting results of these trials.

Human immunodeficiency virus acquisition associated with genital ulcer disease and herpes simplex virus type 2 infection: a nested case-control study in Rakai, Uganda

To assess the timing of symptomatic genital ulcer disease (GUD) relative to human immunodeficiency virus (HIV) seroconversion, we studied 248 case subjects who underwent HIV seroconversion and 496 HIV-negative control subjects, at 3 interview visits conducted at 10-month intervals: visit 1, before HIV acquisition; visit 2, after seroconversion; and visit 3, 10 months after detection of seroconversion. Odds ratios (ORs) and 95% confidence intervals (CIs), for HIV acquisition, were estimated by logistic regression. HIV load was measured by RNA-polymerase chain reaction, and herpes simplex virus type 2 (HSV-2) serologic testing used HerpeSelect EIA with Western blot confirmation. The OR of HSV-2 seropositivity associated with HIV acquisition was 1.7 (95% CI, 1.2-2.4). Prevalence of GUD was increased among case subjects, at visits 2 (OR, 3.2; 95% CI, 1.9-5.3) and 3 (OR, 2.1; 95% CI, 1.1-3.9). HIV load was increased in HSV-2-seropositive case subjects, compared with that in HSV-2-seronegative subjects, at 5 (P=.04) and 15 (P=.02) months after seroconversion. HIV acquisition is associated with HSV-2 seropositivity, and GUD is increased after seroconversion. HIV load is increased in HSV-2-positive subjects who seroconverted, suggesting a role for treatment of HSV-2 infection in HSV-2-seropositive, dually infected individuals.

Stochastic simulation of the impact of antiretroviral therapy and HIV vaccines on HIV transmission; Rakai, Uganda

OBJECTIVE

To model the effects of antiretroviral therapy (ART) and HIV vaccines on HIV transmission using empirical data from studies in Rakai, Uganda.

DESIGN

A stochastic simulation model estimated HIV incidence, probabilities of transmission per coital act and the reproductive number (R0) with ART and HIV vaccines. Model inputs included Rakai data on HIV transmission probabilities per coital act by HIV viral load, age and gender, and sexual behaviors. The impacts of therapy were derived from US programs, and vaccine assumptions included preventive efficacies ranging from 25 to 75%. Component projection models estimated the numbers of HIV-infected persons over 20 years.

RESULTS

The model incidence [1.57/100 person years (PY)] closely fitted empirical data (1.5/100 PY). Simulations of ART using DHHS treatment guidelines, predicted declines in HIV incidence, but R0 remained > 1.0, and the numbers of HIV-positive persons did not change substantially over 20 years. Preventive vaccines with > 50% efficacy and > 50% population coverage could reduce R0 to < 1.0, and substantially reduce the number of HIV-infected persons over 20 years. Concurrent ART and a preventive vaccine can have substantial impact at lower levels of population coverage and would markedly reduce the HIV infected population over 20 years. However, behavioral disinhibition with increased numbers of sexual partners in either ART or vaccine recipients, increased HIV incidence and diminished intervention impact.

CONCLUSION

ART alone cannot control the HIV epidemic in mature epidemics such as Rakai, and persons in need of therapy will increase over time. ART in combination with a low efficacy vaccine could control the epidemic, if behavioral disinhibition is prevented.

Age differences in sexual partners and risk of HIV-1 infection in rural Uganda

OBJECTIVES

To assess whether differences in age between sexual partners affect the risk of HIV infection in female adolescents and young adults.

METHODS

A total of 6177 ever sexually active women aged 15 to 29 years completed a sociodemographic and sexual behavior questionnaire and provided a blood sample for HIV-1 serology. The age difference between partners was categorized as men 0 to 4 years older (referent group), 5 to 9 years older and 10 or more years older. HIV prevalence and incidence were assessed, and adjusted RR was estimated by multivariate regression.

RESULTS

Prevalent HIV-1 infection in female participants increased with older male sexual partners. Among women aged 15 to 19 years, the adjusted risk of HIV infection doubled (RR = 2.04; 95% CI: 1.29-3.22) among those reporting male partners 10 or more years older compared with those with male partners 0 to 4 years older; among women 20 to 24 years of age, the RR was 1.24 (95% CI: 0.96-1.60). The attributable fraction (exposed) of prevalent HIV infection in women aged 15 to 24 years associated with partners 10 or more years older was 9.7% (95% CI: 5.2-14.0). HIV incidence did not increase with differences in age of partners.

CONCLUSION

The age difference between young women and their male partners is a significant HIV risk factor, suggesting that high HIV prevalence in younger women is caused, in part, by transmission from older male partners.

Hormonal contraceptive use and HIV-1 infection in a population-based cohort in Rakai, Uganda

BACKGROUND

Hormonal contraceptives have been associated with increased risk of HIV acquisition.

METHODS

The association between hormonal contraception use and HIV acquisition was assessed in a rural community-based cohort in Rakai District, Uganda. A group of 5117 sexually active HIV-negative women were surveyed at 10 month intervals between 1994 and 1999. Information on demographic and sociobehavioral characteristics, use of hormonal contraception (pill and injectable methods), condoms and the number of sexual partners was obtained by home-based interview. HIV incidence rate ratios (IRR) and 95% confidence intervals (CI) associated with hormonal contraception were estimated by multivariate Poisson regression after adjustment for age, condom use, number of sexual partners, marital status, education and history of genital ulcer disease.

RESULTS

At one or more interviews, 16.6% of women reported use of hormonal contraceptives and 23.0% reported condom use. HIV incidence was 2.3/100 person-years in hormonal contraceptive users compared with 1.5/100 person-years in non-hormonal contraceptive users (unadjusted IRR, 1.56; 95% CI, 1.00-2.33). After multivariate adjustment, the IRR associated with hormonal contraceptives was reduced to 0.94 (95% CI, 0.53-1.64). The adjusted IRR was 1.12 (95% CI, 0.48-2.56) with oral contraceptive use and 0.84 (95%CI, 0.41-1.72) with injectable methods.

CONCLUSION

Use of hormonal contraception is not associated with HIV acquisition after adjustment for behavioral confounding.

HIV dynamics and behaviour change as determinants of the impact of sexually transmitted disease treatment on HIV transmission in the context of the Rakai trial

OBJECTIVE

To assess how the impact of sexually transmitted disease (STD) treatment on HIV incidence varies between stages of the HIV epidemic.

METHODS

We simulated the spread of curable STD, herpes simplex virus type 2 and HIV in the dynamic transmission model. Parameters were quantified to represent a severe HIV epidemic as in Rakai, Uganda, using demographic, behavioural and epidemiological data from a recent STD treatment trial.

RESULTS

The model fitted the HIV epidemic in Rakai if we assumed a considerable behavioural risk reduction, starting at the end of the Ugandan civil war in 1986. An improvement in STD treatment reduced HIV incidence in this population by 35% over 2 years if implemented in 1981, but only by 11 and 8% in 1988 or 1998. This trend resulted partly from the hypothesized behaviour change, which markedly reduced the prevalences of bacterial STD. In a simulated epidemic without behavioural change, the corresponding treatment impacts in 1988 and 1998 would be 19 and 15%. Enhanced herpetic ulceration in immunocompromised HIV patients contributed little to the reduced impact of treatment of bacterial STD over time.

CONCLUSION

In HIV epidemics beyond the first decade, the impact of STD treatment programmes on HIV transmission may depend more on behavioural risk reduction than on the stage of the epidemic. Preceding behavioural change associated with restored civil stability may have contributed to the lack of impact of STD treatment on HIV in the Rakai trial. In advanced epidemics with less behaviour change, STD treatment may still be important for HIV prevention.

What proportion of episodes of gonorrhoea and chlamydia becomes symptomatic?

The effectiveness of syndromic treatment as an STD control strategy depends on the proportion of episodes which become symptomatic; few studies have measured this directly. We estimated these proportions for gonorrhoea (NG) and chlamydia (CT), synthesizing data on the point prevalence of self-reported discharge and dysuria among infected cases in rural Uganda, the durations of symptoms, incubation period and asymptomatic episodes, and the effect of treatment on symptom duration. Estimated proportions of episodes that become symptomatic were 45% for males with NG, 11% for males with CT, 14% for females with NG and 6% for females with CT. This was on average 1.5-fold higher than symptom prevalence at cross-section among infected cases in this population. Estimates were sensitive to assumptions on the relative durations of asymptomatic and symptomatic episodes, but were invariably inconsistent with previous direct estimates based on a US cohort study. These results show that the probability of recognizing symptoms in NG and CT episodes varies between settings. In populations with low treatment rates like Uganda, these probabilities can be very low. Here, health education should have priority in STD management programmes.

Population-based HIV testing and counseling in rural Uganda: participation and risk characteristics

OBJECTIVES

To assess self-selection in a population-based voluntary HIV testing and counseling (VTC) program by comparing the HIV risk characteristics of users and nonusers of VTC in rural Uganda.

DESIGN

A 1994 to 1995 community-randomized trial in the Rakai District of Uganda enrolled adults aged 15 to 59 years and ascertained their HIV status, sociodemographic characteristics, risk behaviors, and AIDS-associated symptoms. All subjects were offered confidential individual VTC at no cost.

METHODS

We compared users and nonusers of VTC among 10,950 participants (4764 male and 6186 female) enrolled at baseline using multivariate logistic regression.

RESULTS

Women were significantly less likely to receive VTC than men (31.5% vs. 34.8%, p <.001). In multivariate analysis, younger age, HIV-positive status, and having no sexual partners in the past 5 years (and, significant for women only, having 2 or more sexual partners) were associated with lower VTC participation for both men and women. Among women, higher VTC participation was associated with symptoms suggestive of AIDS and other illnesses and shopkeeper occupations.

CONCLUSIONS

During the initial phase of a population-based free VTC program in rural Uganda, certain high-risk groups were underrepresented among VTC recipients. There is a need to target VTC to ensure participation by high-risk individuals most in need of services.

HIV incidence and sexually transmitted disease prevalence associated with condom use: a population study in Rakai, Uganda

OBJECTIVE

Evidence of condom effectiveness for HIV and sexually transmitted disease (STD) prevention is based primarily on high-risk populations. We examined condom effectiveness in a general population with high HIV prevalence in rural Africa.

METHODS

Data were from a randomized community trial in Rakai, Uganda. Condom usage information was obtained prospectively from 17,264 sexually active individuals aged 15-59 years over a period of 30 months. HIV incidence and STD prevalence was determined for consistent and irregular condom users, compared to non-users. Adjusted rate ratios (RR) of HIV acquisition were estimated by Poisson multivariate regression, and odds ratios of STDs estimated by logistic regression.

RESULTS

Only 4.4% reported consistent condom use and 16.5% reported inconsistent use during the prior year. Condom use was higher among males, and younger, unmarried and better educated individuals, and those reporting multiple sex partners or extramarital relationships. Consistent condom use significantly reduced HIV incidence [RR, 0.37; 95% confidence interval (CI), 0.15-0.88], syphilis [odds ratio (OR), 0.71; 95% CI, 0.53-0.94] and gonorrhea/Chlamydia (OR, 0.50; 95% CI, 0.25-0.97) after adjustment for socio-demographic and behavioral characteristics. Irregular condom use was not protective against HIV or STD and was associated with increased gonorrhea/Chlamydia risk (OR, 1.44; 95% CI, 1.06-1.99). The population attributable fraction of consistent use for prevention of HIV was -4.5% (95% CI, -8.3 to 0.0), due to the low prevalence of consistent use in the population.

CONCLUSIONS

Consistent condom use provides protection from HIV and STDs, whereas inconsistent use is not protective. Programs must emphasize consistent condom use for HIV and STD prevention.

Randomized trial of presumptive sexually transmitted disease therapy during pregnancy in Rakai, Uganda

OBJECTIVE

The purpose of this study was to assess presumptive sexually transmitted disease treatment on pregnancy outcome and HIV transmission.

STUDY DESIGN

In a randomized trial in Rakai District, Uganda, 2070 pregnant women received presumptive sexually transmitted disease treatment 1 time during pregnancy at varying gestations, and 1963 control mothers received iron/folate and referral for syphilis. Maternal-infant sexually transmitted disease/HIV and infant outcomes were assessed. Intent-to-treat analyses estimated adjusted rate ratios and 95% confidence intervals.

RESULTS

Sexually transmitted diseases were reduced: Trichomonas vaginalis (rate ratio, 0.28; 95% CI, 0.18%-0.49%), bacterial vaginosis (rate ratio, 0.78; 95% CI, 0.69-0.87), Neisseria gonorrhoeae /Chlamydia trachomatis (rate ratio, 0.43; 95% CI, 0.27-0.68), and infant ophthalmia (rate ratio, 0.37; 95% CI, 0.20-0.70). There were reduced rates of neonatal death (rate ratio, 0.83; 95% CI, 0.71-0.97), low birth weight (rate ratio, 0.68; 95% CI, 0.53-0.86), and preterm delivery (rate ratio, 0.77; 95% CI, 0.56-1.05); but there were no effects on maternal HIV acquisition or perinatal HIV transmission.

CONCLUSION

Reductions of maternal sexually transmitted disease improved pregnancy outcome but not maternal HIV acquisition or perinatal HIV transmission.

Probability of HIV-1 transmission per coital act in monogamous, heterosexual, HIV-1-discordant couples in Rakai, Uganda

BACKGROUND

The probability of HIV-1 transmission per coital act in representative African populations is unknown. We aimed to calculate this probability overall, and to estimate how it is affected by various factors thought to influence infectivity.

METHODS

174 monogamous couples, in which one partner was HIV-1 positive, were retrospectively identified from a population cohort in Rakai, Uganda. Frequency of intercourse and reliability of reporting within couples was assessed prospectively. HIV-1 seroconversion was determined in the uninfected partners, and HIV-1 viral load was measured in the infected partners. Adjusted rate ratios of transmission per coital act were estimated by Poisson regression. Probabilities of transmission per act were estimated by log-log binomial regression for quartiles of age and HIV-1 viral load, and for symptoms or diagnoses of sexually transmitted diseases (STDs) in the HIV-1-infected partners.

RESULTS

The mean frequency of intercourse was 8.9 per month, which declined with age and HIV-1 viral load. Members of couples reported similar frequencies of intercourse. The overall unadjusted probability of HIV-1 transmission per coital act was 0.0011 (95% CI 0.0008-0.0015). Transmission probabilities increased from 0.0001 per act at viral loads of less than 1700 copies/mL to 0.0023 per act at 38 500 copies/mL or more (p=0.002), and were 0.0041 with genital ulceration versus 0.0011 without (p=0.02). Transmission probabilities per act did not differ significantly by HIV-1 subtypes A and D, sex, STDs, or symptoms of discharge or dysuria in the HIV-1-positive partner.

INTERPRETATION

Higher viral load and genital ulceration are the main determinants of HIV-1 transmission per coital act in this Ugandan population.

Prevalence of Kaposi sarcoma-associated herpesvirus compared with selected sexually transmitted diseases in adolescents and young adults in rural Rakai District, Uganda

BACKGROUND

Kaposi sarcoma-associated herpesvirus (KSHV) is transmitted by routes such as homosexual intercourse and is associated with HIV infection in industrialized countries. However, there is little information about its transmission in developing countries where Kaposi sarcoma is an endemic disease.

GOAL

To examine KSHV seroprevalence in young adults in a general, rural Ugandan population, and to compare this prevalence with rates of known sexually transmitted infections.

STUDY DESIGN

The seroprevalence of KSHV was compared with the epidemiology of sexually transmitted diseases in 523 sexually active subjects aged 15 to 29 years who were randomly selected from a general population cohort in rural Rakai District, Uganda. Participants provided in-home interview data and specimens. Sera were tested for KSHV using immunofluorescence assay and immunoblot for lytically expressed recombinant KSHV ORF65.2. Sera were also tested for HIV type 1, herpes simplex virus type 2, and syphilis.

RESULTS

The prevalence of KSHV was significantly higher in participants 15 to 19 years compared with older persons 25 to 29 years (45.0% and 36.1%, respectively; adjusted odds ratio, 0.48; 95% CI, 0.28-0.82). In contrast, herpes simplex virus type 2 and HIV type 1 prevalence increased with age. Kaposi sarcoma-associated herpesvirus serostatus was not associated with HIV type 1, syphilis, herpes simplex virus type 2, or number of sexual partners. Homosexual and anal intercourse were reported by less than 1% of participants.

CONCLUSIONS

Kaposi sarcoma-associated herpesvirus does not appear to be a heterosexually transmitted infection in rural Uganda.

Mortality associated with HIV infection in rural Rakai District, Uganda

OBJECTIVE

To assess mortality impact of HIV in rural Uganda.

METHODS

An open cohort of 19983 adults aged 15-59 years, in Rakai district was followed at 10 month intervals for four surveys. Sociodemographic characteristics and symptomatology/disease conditions were assessed by interview. Deaths among residents and out-migrants were identified household census. Mortality rates were computed per 1000 person years (py) and the rate ratio (RR) of death in HIV-positive/HIV-negative subjects, and the population attributable fraction (PAF) of death were estimated according to sociodemographic characteristics. Mortality associated with potential AIDS defining symptoms and signs was assessed.

RESULTS

HIV prevalence was 16.1%. Mortality was 132.6 per 1000 py in HIV-infected versus 6.7 per 1000 py in uninfected subjects, and 73.5% of adult deaths were attributable to HIV infection. Mortality increased with age, but the highest attributable risk of HIV associated deaths were observed in persons aged 20-39 years (PAF > 80%) and in women. HIV associated mortality was highest in the better educated (PAF > or = 75%) and among government employees (PAF > or = 82%). Of the HIV-positive subjects 40.5% reported no illness < 10 months preceding death, symptoms were poor predictors of death (sensitivity 1.6-38.8%), and only 9.1% met the World Health Organization clinical definition of AIDS. Infant mortality rates in babies of HIV-infected and uninfected mothers were 209.4 and 97.7 per 1000, respectively.

CONCLUSION

HIV is taking substantial toll in this population, particularly among the younger better educated adults, and infants. Symptomatology or the World Health Organization definition of AIDS are poor predictors of death.

Male circumcision and HIV acquisition and transmission: cohort studies in Rakai, Uganda. Rakai Project Team

BACKGROUND

Male circumcision is associated with reduced HIV acquisition.

METHODS

HIV acquisition was determined in a cohort of 5507 HIV-negative Ugandan men, and in 187 HIV-negative men in discordant relationships. Transmission was determined in 223 HIV-positive men with HIV-negative partners. HIV incidence per 100 person years (py) and adjusted rate ratios (RR) and 95% confidence intervals (CI) were estimated by Poisson regression. HIV-1 serum viral load was determined for the seropositive partners in HIV-discordant couples.

RESULTS

The prevalence of circumcision was 16.5% for all men; 99.1% in Muslims and 3.7% in non-Muslims. Circumcision was significantly associated with reduced HIV acquisition in the cohort as a whole (RR 0.53, CI 0.33-0.87), but not among non-Muslim men. Prepubertal circumcision significantly reduced HIV acquisition (RR 0.49, CI 0.26-0.82), but postpubertal circumcision did not. In discordant couples with HIV-negative men, no serconversions occurred in 50 circumcised men, whereas HIV acquisition was 16.7 per 100 py in uncircumcised men (P = 0.004). In couples with HIV-positive men, HIV transmission was significantly reduced in circumcised men with HIV viral loads less than 50000 copies/ml (P = 0.02).

INTERPRETATION

Prepubertal circumcision may reduce male HIV acquisition in a general population, but the protective effects are confounded by cultural and behavioral factors in Muslims. In discordant couples, circumcision reduces HIV acquisition and transmission. The assessment of circumcision for HIV prevention is complex and requires randomized trials.

Sensitivity and specificity of HIV-1 testing of urine compared with serum specimens: Rakai, Uganda. The Rakai Project Team

BACKGROUND AND OBJECTIVES

To evaluate a urine HIV-1 test.

STUDY DESIGN

Paired urine and blood samples from a sample of 222 subjects were assayed for HIV-1 using Calypte HIV-1 Urine enzyme immunoassay (EIA) with Western blot (WB) confirmation, and sera were tested by EIA and WB. Masked assays were done on stored, refrigerated urine at Johns Hopkins University (JH), and on fresh specimens at the Rakai Project, Entebbe (RP). We assessed the sensitivity and specificity of the urine relative to serum assays.

RESULTS

Compliance with provision of urine samples (95.0%) was higher than provision of serum (90.5%). Ninety-six sera were HIV-positive; 92 were HIV-positive on stored urine at JH (sensitivity 95.8%, CI 91.8-99.8%); and 94 (100%) were positive on fresh samples at the RP laboratory (sensitivity = 100.0%). Among serum HIV-negative subjects, all frozen urine were negative at JH and 97.7% of fresh samples were negative at RP.

CONCLUSIONS

The Calypte urine HIV-1 EIA with WB is sensitive and specific. In this population, provision of urine was more acceptable than provision of blood samples.

Relative risks and population attributable fraction of incident HIV associated with symptoms of sexually transmitted diseases and treatable symptomatic sexually transmitted diseases in Rakai District, Uganda. Rakai Project Team

OBJECTIVES

To assess the linkage of sexually transmitted disease (STD) symptoms and treatable STD to HIV incidence.

DESIGN

Analysis of a randomized trial of STD control for HIV prevention, Rakai, Uganda.

METHODS

Consenting adults 15-59 years of age were seen at 10-monthly home visits, interviewed regarding STD symptoms, and asked to provide samples for HIV and STD diagnoses. HIV incidence was determined in 8089 HIV-negative subjects over 10 457 person years. Adjusted rate ratios (RR) and 95% confidence intervals (CI) of HIV acquisition associated with genital ulcer disease (GUD) and discharge/dysuria were used to estimate the population attributable fraction (PAF) of HIV acquisition. HIV transmission risks associated with STD symptoms in HIV-positive partners of 167 HIV discordant couples and the numbers of sexual partners reported by HIV-positive subjects were used to estimate the PAF of HIV transmission attributable to STD.

RESULTS

HIV prevalence was 16%. The risk of HIV acquisition was increased with GUD (RR 3.14; CI 1.98-4.98) and in males with discharge/dysuria (RR 2.44; CI 1.17-5.12), but not in females with discharge/dysuria. The PAF of HIV acquisition was 9.5% (CI 2.8-15.8%) with any of the three STD symptoms. The PAF for GUD was 8.8% (CI 3.7-13.8), but only 8.2% of reported GUD was caused by treatable syphilis or chancroid . The PAF for discharge/dysuria in males was 6.7% (CI 1.1-13.8), but only 25% of symptomatic males had concurrent gonorrhea or chlamydial infection. No significant differences were seen in PAF between study treatment arms. The PAF of HIV transmission associated with STD symptoms in HIV-positive persons was indirectly estimated to be 10.4%.

CONCLUSION

In this mature, generalized HIV epidemic setting, most HIV seroconversion occurs without recognized STD symptoms or curable STD detected by screening. Therefore, syndromic management or other strategies of STD treatment are unlikely to substantially reduce HIV incidence in this population. However, STD is associated with significant HIV risk at the individual level, and STD management is needed to protect individuals.

Use of a hybrid capture assay of self-collected vaginal swabs in rural Uganda for detection of human papillomavirus

A random sample of 960 women aged 15-59 years enrolled in a population-based study in rural Uganda were asked to provide self-collected vaginal swabs for human papillomavirus (HPV) testing by hybrid capture assay. The intensity of HPV infection was assessed by the relative light unit (RLU) ratio in the specimen-to-positive control (PC) ratio. In total, 898 women (93%) provided a swab and 737 provided serum for human immunodeficiency virus type 1 (HIV-1) determination. HPV prevalence was 16.7% and was highest in younger women. HIV-1 prevalence was 17.8%. HPV prevalence was 44.3% in HIV-positive and 10.2% in HIV-negative women (rate ratio, 5.36; 95% confidence interval, 3.81-7.54). The intensity of HPV infection was significantly greater among HIV-positive than HIV-negative women (54. 4 vs. 11.1 RLU/PC; P=.026); intensity of infection was highest in women aged <30 years. The higher prevalence and intensity of HPV infection in HIV-positive women could facilitate HPV transmission in this population. Self-collected vaginal swabs could be used in population-based screening to identify women at high risk of cervical neoplasia.

Age of male circumcision and risk of prevalent HIV infection in rural Uganda

OBJECTIVE

To assess whether circumcision performed on postpubertal men affords the same level of protection from HIV-1 acquisition as circumcisions earlier in childhood.

DESIGN

Cross-sectional study of a population-based cohort.

SETTING

Rakai district, rural Uganda.

METHODS

A total of 6821 men aged 15-59 years were surveyed and venous blood samples were tested for HIV-1 and syphilis. Age at circumcision was dichotomized into men who were circumcised before or at age 12 years (prepubertal) and men circumcised after age 12 years (postpubertal). Postpubertal circumcised men were also subdivided into those reporting circumcision at ages 13-20 years and > or = 21 years.

RESULTS

HIV-1 prevalence was 14.1% in uncircumcised men, compared with 16.2% for men circumcised at age > or = 21 years, 10.0% for men circumcised at age 13-20 years, and 6.9% in men circumcised at age < or = 12 years. On bivariate analysis, lower prevalence of HIV-1 associated with prepubertal circumcision was observed in all age, education, ethnic and religious groups. Multivariate adjusted odds ratio of prevalent HIV-1 infection associated with prepubertal circumcision was 0.39 [95% confidence interval (CI), 0.29-0.53]. In the postpubertal group, the adjusted odds ratio for men circumcised at ages 13-20 years was 0.46 (95% CI, 0.28-0.77), and 0.78 (95% CI, 0.43-1.43) for men circumcised after age 20 years.

CONCLUSIONS

Prepubertal circumcision is associated with reduced HIV risk, whereas circumcision after age 20 years is not significantly protective against HIV-1 infection. Age at circumcision and reasons for circumcision need to be considered in future studies of circumcision and HIV risk.

Control of sexually transmitted diseases for AIDS prevention in Uganda: a randomised community trial. Rakai Project Study Group

BACKGROUND

The study tested the hypothesis that community-level control of sexually transmitted disease (STD) would result in lower incidence of HIV-1 infection in comparison with control communities.

METHODS

This randomised, controlled, single-masked, community-based trial of intensive STD control, via home-based mass antibiotic treatment, took place in Rakai District, Uganda. Ten community clusters were randomly assigned to intervention or control groups. All consenting residents aged 15-59 years were enrolled; visited in the home every 10 months; interviewed; asked to provide biological samples for assessment of HIV-1 infection and STDs; and were provided with mass treatment (azithromycin, ciprofloxacin, metronidazole in the intervention group, vitamins/anthelmintic drug in the control). Intention-to-treat analyses used multivariate, paired, cluster-adjusted rate ratios.

FINDINGS

The baseline prevalence of HIV-1 infection was 15.9%. 6602 HIV-1-negative individuals were enrolled in the intervention group and 6124 in the control group. 75.0% of intervention-group and 72.6% of control-group participants provided at least one follow-up sample for HIV-1 testing. At enrolment, the two treatment groups were similar in STD prevalence rates. At 20-month follow-up, the prevalences of syphilis (352/6238 [5.6%]) vs 359/5284 [6.8%]; rate ratio 0.80 [95% CI 0.71-0.89]) and trichomoniasis (182/1968 [9.3%] vs 261/1815 [14.4%]; rate ratio 0.59 [0.38-0.91]) were significantly lower in the intervention group than in the control group. The incidence of HIV-1 infection was 1.5 per 100 person-years in both groups (rate ratio 0.97 [0.81-1.16]). In pregnant women, the follow-up prevalences of trichomoniasis, bacterial vaginosis, gonorrhoea, and chlamydia infection were significantly lower in the intervention group than in the control group. No effect of the intervention on incidence of HIV-1 infection was observed in pregnant women or in stratified analyses.

INTERPRETATION

We observed no effect of the STD intervention on the incidence of HIV-1 infection. In the Rakai population, a substantial proportion of HIV-1 acquisition appears to occur independently of treatable STD cofactors.

HIV enteropathy: comparative morphometry of the jejunal mucosa of HIV infected patients resident in the United Kingdom and Uganda

AIMS

To compare jejunal mucosal morphometry in HIV infected patients resident in London and Uganda.

PATIENTS

Twenty HIV positive patients from London and 16 from Uganda were studied, and compared with HIV negative control subjects from both sites.

METHODS

Stools and biopsy specimens were examined for enteropathogens. Surface area to volume (S:V) ratio was estimated morphometrically, mean crypt length of jejunal biopsy specimens was measured, and HIV infected cells detected immunohistochemically were quantified.

RESULTS

Enteric pathogens were detected in none of the London patients, and in three Ugandan patients. S:V ratio was lower, and mean crypt length higher, in the specimens of London patients than in normal subjects, but there was no difference in S:V ratio or mean crypt length between Ugandan patients and controls. A negative correlation was present between S:V ratio and mean crypt length in all biopsy specimens analysed. HIV infected cells were detected only in lamina propria.

CONCLUSION

Infection of cells in the lamina propria of the jejunum with HIV stimulates crypt cell proliferation, and a fall in villous surface area. The mucosal response to HIV is masked by other pathogens in the African environment.

Lack of efficacy of low dose oral interferon alfa in symptomatic HIV-1 infection: a randomised, double blind, placebo controlled trial

BACKGROUND

Interferon alfa (IFN-alpha) exhibits dose related in vitro activity against human immunodeficiency virus (HIV), with complete inhibition of HIV replication at IFN-alpha concentrations > or = 256 IU/ml. In mid-1990, Kenyan investigators reported that oral administration of an extremely low dose (150 IU/day) of natural human (nHu) IFN-alpha resulted in complete alleviation of AIDS related complex and AIDS symptoms and resolution of opportunistic infections without additional treatment. Moreover, loss of HIV antibody seropositivity was reported in approximately 10% of treated patients. Subsequent small studies failed to substantiate these spectacular claims, but controversy on the efficacy of this treatment persisted.

METHODS

We studied 559 adult Ugandan patients with WHO stage 2-4 HIV infection and a Karnofsky performance score of more than 50, who had not received any drugs with antiretroviral activity in the previous 3 months. The patients were randomly assigned in a double blind fashion either to 150 IU oral nHuIFN-alpha/day or placebo. The duration of treatment was extended from 28 weeks to 60 weeks 9 months after enrollment had started. At that time 112 subjects had already received 28 weeks of treatment and been discontinued from the study.

RESULTS

Both study groups were comparable with respect to all baseline characteristics studied, except that the nHuIFN-alpha group had slightly lower absolute CD4+ lymphocyte counts (median 60.7 x 10(6)/l) than the placebo group (median 85.3 x 10(6)/l) (p = 0.033). Therefore, all analyses were adjusted for CD4+ lymphocyte counts at entry. In both treatment groups there was relentless progression of HIV disease. Subjects treated with nHuIFN-alpha and placebo had similar mortality, disease progression rates, decline of CD4+ lymphocyte counts and Karnofsky performance scores, and prevalence of symptoms. No patient reverted to HIV-1 seronegative antibody status. Serious adverse events were not seen. Quality control of the study medication documented that the active drug indeed contained IFN-alpha activity.

CONCLUSIONS

The current large, randomised, double blind, placebo controlled study did not show any benefit from oral treatment with 150 IU nHuIFN-alpha/day in a population of African patients with symptomatic HIV infection.

A randomized, community trial of intensive sexually transmitted disease control for AIDS prevention, Rakai, Uganda

OBJECTIVE

To describe the design and first-round survey results of a trial of intensive sexually transmitted disease (STD) control to reduce HIV-1 incidence.

STUDY DESIGN

Randomized, controlled, community-based trial in Rakai District, Uganda.

METHODS

In this ongoing study, 56 communities were grouped into 10 clusters designed to encompass social/sexual networks; clusters within blocks were randomly assigned to the intervention or control arm. Every 10 months, all consenting resident adults aged 15-59 years are visited in the home for interview and sample collection (serological sample, urine, and, in the case of women, self-administered vaginal swabs). Sera are tested for HIV-1, syphilis, gonorrhea, chlamydia, trichomonas and bacterial vaginosis. Following interview, all consenting adults are offered directly observed, single oral dose treatment (STD treatment in the intervention arm, anthelminthic and iron-folate in the control arm). Treatment is administered irrespective of symptoms or laboratory testing (mass treatment strategy). Both arms receive identical health education, condom and serological counseling services.

RESULTS

In the first home visit round, the study enrolled 5834 intervention and 5784 control arm subjects. Compliance with interview, sample collection and treatment was high in both arms (over 90%). Study arm populations were comparable with respect to sociodemographic and behavioral characteristics, and baseline HIV and STD rates. The latter were high: 16.9% of all subjects were HIV-positive, 10.0% had syphilis, and 23.8% of women had trichomonas and 50.9% had bacterial vaginosis.

CONCLUSIONS

Testing the effects of STD control on AIDS prevention is feasible in this Ugandan setting.

Trends in HIV-1 prevalence may not reflect trends in incidence in mature epidemics: data from the Rakai population-based cohort, Uganda

OBJECTIVES

To assess whether trends in serial HIV-1 prevalence reflect trend in HIV incidence, and to decompose the effects of HIV-1 incidence, mortality, mobility and compliance on HIV-1 prevalence in a population-based cohort.

DESIGN

Two-year follow up (1990-1992) of an open cohort of all adults aged 15-59 years, resident in a sample of 31 representative community clusters in rural Rakai District, Uganda.

METHODS

A detailed household enumeration was concluded at baseline and in each subsequent year. All household residents were listed, and all deaths and in- and out-migrations that occurred in the intersurvey year wee recorded. In each year, all consenting adults were interviewed and provided a serological sample; 2591 adults aged 15-59 years were enrolled at baseline.

RESULTS

HIV prevalence among adults declined significantly 1990 and 1992 (23.4% at baseline, 21.8% in 1991, 20.9% in 1992; P < 0.05). Declining prevalence was also observed in subgroups, including young adults aged 15-24 years (from 20.6 to 16.2% over 3 years; P < 0.02), women of reproductive age (from 27.1 to 23.5%; P < 0.05), and pregnant women (from 25.4 to 20.0%; not significant), However, HIV incidence did not change significantly among all adults aged 15-59 years (2.1 +/- 0.4 per 100 person-years of observation (PYO) in 1990-1991 and 2.0 +/- 0.3 per 100 PYO in 1991-1992], nor in population subgroups. HIV-related mortality was high (13.5 per 100 PYO among the HIV-positive), removing more infected persons that were added by seroconversion. Net out-migration also removed substantial numbers of HIV-positive individuals.

CONCLUSIONS

In this mature HIV epidemic, HIV prevalence declined in the presence of stable and incidence. HIV-related mortality contributed most to the prevalence decline. Prevalence was not an adequate surrogate measure of incidence, limiting the utility or serial prevalence measures in assessing the dynamics of the HIV epidemic and in evaluating the impact of current preventive strategies.

Adolescents, sexual behaviour and HIV-1 in rural Rakai district, Uganda

OBJECTIVES

To describe the epidemiology of HIV-1 infection among adolescents aged 13-19 years, in rural Rakai district, Uganda.

STUDY DESIGN

Baseline survey and 2-year follow-up (1990-1992) of adolescents in a population-based, open rural cohort.

METHODS

Annual enumeration and behavioral/serological survey of all consenting adolescents aged 13-19 years at recruitment, residing in 31 randomly selected community clusters.

RESULTS

At baseline, of 909 adolescents present in study clusters, 824 (90.6%) provided interview data and serological samples. No adolescents aged 13-14 years were HIV-infected. Among those aged 15-19 years, 1.8% of men and 19.0% of women were HIV-positive. Among young women aged 15-19 years in marital/consensual union, 21.3% were HIV-positive; this rate did not differ significantly from the 29.1% prevalence in those reporting non-permanent relationships; prevalence was significantly lower in women reporting no current relationship (4.3%). After multivariate adjustment, female sex, age 17-19 years, residence in trading centers/trading villages and a history of sexually transmitted disease symptoms remained significantly associated with HIV infection. Seventy-nine per cent of adolescents provided a follow-up serological sample. No young men aged 13-14 years seroconverted during the study; in young women aged 13-14 years, HIV seroincidence was 0.6 per 100 person-years (PY) of observation. Among young men aged 15-19 years, there were 1.1 +/- 0.6 seroconversions per 100 PY of observation prior to age 21 years; among women 15-19 years, the incidence rate was 3.9 +/- 1.0 per 100 PY of observation prior to age 21 years. The mortality rate among HIV-positive adolescents aged 15-19 years, at 3.9 per 100 PY of observation, was 13-fold higher than that among the HIV-uninfected. By 1992, knowledge of sexual transmission was almost universal, the proportions reporting multiple partners had decreased and condom use had increased over baseline.

CONCLUSIONS

Adolescents, and young women in particular, are vulnerable to HIV infection. Despite reported behavioral changes, HIV incidence rates remain substantial, and there is a need for innovative HIV preventive measures.

The social dynamics of HIV transmission as reflected through discordant couples in rural Uganda

OBJECTIVE

To describe the role of men and women as sources of HIV transmission and to estimate HIV incidence among discordant couples resident in diverse rural communities in Uganda.

SETTING

Rakai, a rural district in Uganda, East Africa.

METHODS

A population-based cohort study, which has been conducted as annual serological and behavioral surveys since 1989. Community clusters were stratified into trading centers on main roads, intermediate trading villages on secondary roads and agricultural villages off roads. In the 1990 survey round, serological data were available for 79 discordant and 411 concordant HIV-negative couples aged 13-49 years. The present analysis examines sex-specific seropositivity associated with place of residence and the incidence of seroconversion among discordant couples between 1990 and 1991.

RESULTS

Seventy-nine discordant couples were followed; the HIV-positive partner was male in 44 couples (57%) and female in 35 couples (43%). There was marked variation in the sex of the seropositive partner by place of residence: women were the HIV-positive partner in 57% of couples from trading centers, 52% from intermediate villages, and 20% from agricultural communities (P < 0.008). Condom use was higher in discordant couples in which the man was the uninfected partner (17.1%) rather than the woman (9.5%). HIV-positive women, but not HIV-positive men, reported significantly more sexual partners and more genital ulcers than seronegative individuals of the same sex. Seroincidence rates among men and women in discordant relationship were 8.7 and 9.2 per 100 person-years (PY), respectively, which was much higher than in concordant seronegative couples (men, 0.82; women, 0.87 per 100 PY).

CONCLUSIONS

In this Ugandan population, men are the predominant source of new infections in rural villages. Risk factors and preventive behaviors vary with the sex of the infected partner, and seroconversion rates are similar in both sexes.

Demographic impact of HIV infection in rural Rakai district, Uganda: results of a population-based cohort study

OBJECTIVES

To examine HIV-1-related mortality and demographic impact in a high HIV prevalence rural district of Uganda.

DESIGN

One-year follow-up (1990-1991) in a population-based rural cohort.

SETTING AND PARTICIPANTS

Annual enumeration of all consenting residents of 1945 households in 31 randomly selected community clusters in Rakai District. Subjects provided yearly HIV serological samples, behavioral and health information.

MAIN OUTCOME MEASURE

Mortality in HIV-infected and uninfected persons.

RESULTS

Mortality among HIV-seropositive adults aged > or = 15 years of 118.4 per 1000 person-years (PY) was substantially higher than in HIV-seronegative adults [12.4 per 1000 PY; relative risk (RR), 9.5; 95% confidence interval (CI), 6.0-14.9]. Infant mortality among offspring of HIV-infected mothers was almost double that for uninfected women (210 compared with 111 per 1000 live births; RR, 1.9; 95% CI, 1.0-3.5). Adult HIV-related mortality was associated with HIV prevalence and, in this cohort, with higher education, non-agricultural occupation and residence in roadside trading centers. We estimate that adult HIV prevalence in the district is 13% and adult HIV attributable mortality 52%. For all ages combined, district HIV attributable mortality is 28%.

CONCLUSION

HIV is the leading cause of adult death in Rakai. Its effects on mortality are particularly marked in the most economically active sectors. However, the overall crude birth rate in the district (45.7 per 1000 population) remains higher than the crude death rate (28.1 per 1000 population), resulting in continued rapid population growth.

Incidence of HIV-1 infection in a rural region of Uganda

OBJECTIVE

To determine the incidence of infection with HIV-1 and the risk factors associated with seroconversion in three geographical strata of a rural Ugandan district.

DESIGN

Serological, sociodemographic, and behavioural surveys of everyone aged 13 or more in 21 randomly selected communities at baseline and one year later.

SETTING

Rural population of Rakai district, southwestern Uganda, residing in main road trading centres, secondary trading villages, and agricultural villages.

SUBJECTS

In 1989, 1292 adults provided a blood sample and interview data; one year later, 778 survivors (77%) who had been seronegative at baseline provided follow up data.

MAIN OUTCOME MEASURES

Incidence of HIV infection in relation to individual characteristics and risk factors, including place of residence.

RESULTS

Incidence of HIV infection in all adults was 2.1/100 person years of observation (SE 0.5 (95% confidence interval 1.1 to 3.1)); in people aged 15-39 the incidence was 3.2/100 person years. Incidence was highest in men and women aged 20-24 (9.2/100 person years (3.9) and 6.8/100 person years (2.9) respectively). Risk factors significantly associated with seroconversion were age 24 and under and two or more sexual partners. Between the surveys the proportion of all respondents reporting high risk behaviour (two or more partners) significantly increased from 8.9% to 12.3%.

CONCLUSIONS

Despite preventive programmes and substantial knowledge about AIDS the incidence of HIV infection remains high in this rural population. Prevention aimed at vulnerable rural communities is urgently needed to contain the HIV epidemic.

HIV risk factors in three geographic strata of rural Rakai District, Uganda

OBJECTIVES

To examine risk factors for HIV-1 infection in three geographic strata (main road trading centers that service local and international traffic, small trading villages on secondary dirt roads that serve as foci for local communications, and agricultural villages off main and secondary roads) in Rakai District, Uganda.

DESIGN AND METHODS

Serological, sociodemographic, knowledge/behaviors and health survey conducted in 21 randomly selected community clusters; complete data were collected for 1292 consenting adults.

RESULTS

Fifteen per cent of the men and 24% of the women were HIV-1-positive. On univariate analysis, several sociodemographic and behavioral factors were significantly associated with risk of HIV infection, including age, place of residence, travel, occupation, marital status, number of sex partners, sex for money or gifts, history of sexually transmitted disease (STD), and history of injections. On multivariate analysis, age, residence and number of sex partners remained significantly associated with HIV infection in both sexes; a history of STD and not having been circumcised were significant in men. There was a significant interaction between place of residence and reported number of sex partners: for any given level of sexual activity, the risk of HIV infection was markedly increased if the background community prevalence was high.

CONCLUSION

Sexual transmission appears to be the primary behavioral risk factor for infection, but the risks associated with this factor vary substantially between the three geographic strata. These data can be used to design targeted interventions.

Dynamics of spread of HIV-I infection in a rural district of Uganda

OBJECTIVE

To define the geographical distribution of HIV infection and the community characteristics associated with HIV prevalence in a rural population of Uganda.

DESIGN

Seroprevalence survey and interviews of the population aged 13 years and older in 21 randomly selected clusters.

SETTING

Rural population of Rakai district, south west Uganda.

SUBJECTS

1292 adults, of whom 594 men and 698 women gave a blood sample and answered the questionnaire.

MAIN OUTCOME MEASURES

HIV status determined by ELISA and western blotting in relation to community characteristics.

RESULTS

The weighted seroprevalence of HIV for the district was 12.6% with prevalence by cluster varying from 1.2% to 52.8%. Seroprevalence was highest in main road trading centres (men 26%, women 47%), intermediate in rural trading villages on secondary roads (men 22%, women 29%), and lowest in rural agricultural villages (men 8%, women 9%). For both men and women, multiple regression showed a strong negative association between cluster seroprevalence and the proportion of the population employed in agriculture (beta = -0.677 for men, -0.807 for women). Among women, cluster seroprevalence increased with a higher proportion of the population reporting multiple sex partners (beta = 0.814), external travel (beta = 0.579), and injections (beta = 0.483).

CONCLUSIONS

Community characteristics, particularly the proportion of the population in agriculture, are associated with HIV prevalence and can be used for targeting interventions. The seroprevalences of HIV suggest spread of infection from main road trading centres, through intermediate trading villages, to rural agricultural villages.

Immunological effects of HIV-1 infection on the humoral response to malaria in an African population

We conducted a cross-sectional study to determine the serological response to malaria in an HIV-1 infected population and in a control population in a region of high malaria transmission. The study group consisted of 66 hospitalized patients with clinical acquired immunodeficiency syndrome (AIDS) and 70 trauma patients without clinical AIDS (controls). Mean optical densities of antibody produced against RESA-4, RESA-8, RESA-11, (PNAN)5 and (NAAG)5 synthetic peptides of Plasmodium falciparum were compared between HIV-1 seropositive and HIV-1 seronegative patients using non-parametric statistics. HIV-1 seropositive patients with clinical AIDS had significantly less antibody to the synthetic P. falciparum ring stage peptide, RESA-8 (P = 0.001), than a comparable group of seronegative patients. Antibody levels were also low for the other ring stage peptides, RESA-4 (P = 0.024) and RESA-11 (P = 0.024). Although not statistically significant, antibody levels among the HIV-1 seropositive trauma patients were higher than among the HIV-1 seronegative trauma patients. During HIV-1 infection, a polyclonal B cell activation may occur as noted in the HIV-1 seropositive trauma patients, but with increased immunosuppression in advanced clinical AIDS, B cell stimulation appears to be diminished. This results in decreased production of malaria antibody.