Incidence of Health Facility Switching and Associations With HIV Viral Rebound Among Persons on Antiretroviral Therapy in Uganda: A Population-based Study.

BACKGROUND: A substantial proportion of persons on antiretroviral therapy (ART) considered lost to follow-up have actually transferred their human immunodeficiency virus (HIV) care to other facilities. However, the relationship between facility switching and virologic outcomes, including viral rebound, is poorly understood. METHODS: We used data from 40 communities (2015-2020) in the Rakai Community Cohort Study to estimate incidence of facility switching and viral rebound. Persons aged 15-49 years with serologically confirmed HIV who self-reported ART use and contributed ≥1 follow-up visit were included. Facility switching and virologic outcomes were assessed between 2 consecutive study visits (ie, index and follow-up visits, interval of approximately 18 months). Those who reported different HIV treatment facilities between index and follow-up study visits were classified as having switched facilities. Virologic outcomes included viral rebound among individuals initially suppressed (<200 copies/mL). Multivariable Poisson regression was used to estimate associations between facility switching and viral rebound. RESULTS: Overall, 2257 persons who self-reported ART use (median age, 35 years; 65% female, 92% initially suppressed) contributed 3335 visit-pairs and 5959 person-years to the analysis. Facility switching was common (4.8 per 100 person-years; 95% confidence interval [CI], 4.2-5.5) and most pronounced in persons aged <30 years and fishing community residents. Among persons suppressed at their index visit (n = 2076), incidence of viral rebound was more than twice as high in persons who switched facilities (adjusted incidence rate ratio = 2.27; 95% CI, 1.16-4.45). CONCLUSIONS: Facility switching was common and associated with viral rebound among persons initially suppressed. Investments in more agile, person-centered models for mobile clients are needed to address system inefficiencies and bottlenecks that can disrupt HIV care continuity.

Age Patterns of HSV-2 Incidence and Prevalence in Two Ugandan Communities: A Catalytic Incidence Model Applied to Population-Based Seroprevalence Data.

BACKGROUND: Herpes simplex virus type 2 (HSV-2) is an incurable sexually transmitted infection associated with increased risk of acquiring and transmitting human immunodeficiency virus (HIV). HSV-2 is highly prevalent in sub-Saharan Africa, but population-level estimates of incidence are sparse. METHODS: We measured HSV-2 prevalence from cross-sectional serological data among adults aged 18-49 years in 2 south-central Uganda communities (fishing, inland). We identified risk factors for seropositivity, then inferred age patterns of HSV-2 with a Bayesian catalytic model. RESULTS: HSV-2 prevalence was 53.6% (n = 975/1819; 95% confidence interval, 51.3%-55.9%). Prevalence increased with age, was higher in the fishing community, and among women, reaching 93.6% (95% credible interval, 90.2%-96.6%) by age 49 years. Factors associated with HSV-2 seropositivity included more lifetime sexual partners, HIV positive status, and lower education. HSV-2 incidence peakied at age 18 years for women and 19-20 years for men. HIV prevalence was up to 10-fold higher in HSV-2-positive individuals. CONCLUSIONS: HSV-2 prevalence and incidence were extremely high, with most infections occurring in late adolescence. Interventions against HSV-2, such as future vaccines or therapeutics, must target young populations. Remarkably higher HIV prevalence among HSV-2-positive individuals underscores this population as a priority for HIV prevention.

Severe Acute Respiratory Syndrome Coronavirus-2 seroprevalence in South-Central Uganda, during 2019-2021.

BACKGROUND: Globally, key subpopulations such as healthcare workers (HCW) may have a higher risk of contracting SARS-CoV-2. In Uganda, limited access to Personal Protective Equipment and lack of clarity on the extent/pattern of community spread may exacerbate this situation. The country established infection prevention/control measures such as lockdowns and proper hand hygiene. However, due to resource limitations and fatigue, compliance is low, posing continued onward transmission risk. This study aimed to describe extent of SARS-CoV-2 seroprevalence in selected populations within the Rakai region of Uganda. METHODS: From 30th November 2020 to 8th January 2021, we collected venous blood from 753 HCW at twenty-six health facilities in South-Central Uganda and from 227 population-cohort participants who reported specific COVID-19 like symptoms (fever, cough, loss of taste and appetite) in a prior phone-based survey conducted (between May and August 2020) during the first national lockdown. 636 plasma specimens collected from individuals considered high risk for SARS-CoV-2 infection, prior to the first confirmed COVID-19 case in Uganda were also retrieved. Specimens were tested for antibodies to SARS-CoV-2 using the CoronaChek™ rapid COVID-19 IgM/IgG lateral flow test assay. IgM only positive samples were confirmed using a chemiluminescent microparticle immunoassay (CMIA) (Architect AdviseDx SARS-CoV-2 IgM) which targets the spike protein. SARS-CoV-2 exposure was defined as either confirmed IgM, both IgM and IgG or sole IgG positivity. Overall seroprevalence in each participant group was estimated, adjusting for test performance. RESULTS: The seroprevalence of antibodies to SARS-CoV-2 in HCW was 26.7% [95%CI: 23.5, 29.8] with no difference by sex, age, or cadre. We observed no association between PPE use and seropositivity among exposed healthcare workers. Of the phone-based survey participants, 15.6% [95%CI: 10.9, 20.3] had antibodies to SARS-CoV-2, with no difference by HIV status, sex, age, or occupation. Among 636 plasma specimens collected prior to the first confirmed COVID-19 case, 2.3% [95%CI: 1.2, 3.5] were reactive. CONCLUSIONS: Findings suggest high seroprevalence of antibodies to SARS-CoV-2 among HCW and substantial exposure in persons presenting with specific COVID-19 like symptoms in the general population of South-Central Uganda. Based on current limitations in serological test confirmation, it remains unclear whether seroprevalence among plasma specimens collected prior to confirmation of the first COVID-19 case implies prior SARS-CoV-2 exposure in Uganda.

Prevalence and Predictors of Persistent Human Immunodeficiency Virus Viremia and Viral Rebound After Universal Test and Treat: A Population-Based Study.

BACKGROUND: There are limited data on individual human immunodeficiency virus (HIV) viral load (VL) trajectories at the population-level after the introduction of universal test and treat (UTT) in sub-Saharan Africa. METHODS: Human immunodeficiency virus VLs were assessed among HIV-positive participants through 3 population-based surveys in 4 Ugandan fishing communities surveyed between November 2011 and August 2017. The unit of analysis was a visit-pair (2 consecutive person-visits), which were categorized as exhibiting durable VL suppression, new/renewed VL suppression, viral rebound, or persistent viremia. Adjusted relative risks (adjRRs) and 95% confidence intervals (CIs) of persistent viremia were estimated using multivariate Poisson regression. RESULTS: There were 1346 HIV-positive participants (n = 1883 visit-pairs). The population-level prevalence of durable VL suppression increased from 29.7% to 67.9% during UTT rollout, viral rebound declined from 4.4% to 2.7%, and persistent viremia declined from 20.8% to 13.3%. Younger age (15-29 vs 40-49 years; adjRR = 1.80; 95% CI = 1.19-2.71), male sex (adjRR = 2.09, 95% CI = 1.47-2.95), never being married (vs currently married; adjRR = 1.88, 95% CI = 1.34-2.62), and recent migration to the community (vs long-term resident; adjRR = 1.91, 95% CI = 1.34-2.73) were factors associated with persistent viremia. CONCLUSIONS: Despite increases in durable VL suppression during roll out of UTT in hyperendemic communities, a substantial fraction of the population, whose risk profile tended to be younger, male, and mobile, remained persistently viremic.

Adaptive Viral Load Monitoring Frequency to Facilitate Differentiated Care: A Modeling Study From Rakai, Uganda.

BACKGROUND: After scale-up of antiretroviral therapy (ART), routine annual viral load monitoring has been adopted by most countries, but reduced frequency of viral load monitoring may offer cost savings in resource-limited settings. We investigated if viral load monitoring frequency could be reduced while maintaining detection of treatment failure. METHODS: The Rakai Health Sciences Program performed routine, biannual viral load monitoring on 2489 people living with human immunodeficiency virus (age ≥15 years). On the basis of these data, we built a 2-stage simulation model to compare different viral load monitoring schemes. We fit Weibull regression models for time to viral load >1000 copies/mL (treatment failure), and simulated data for 10 000 individuals over 5 years to compare 5 monitoring schemes to the current viral load testing every 6 months and every 12 months. RESULTS: Among 7 monitoring schemes tested, monitoring every 6 months for all subjects had the fewest months of undetected failure but also had the highest number of viral load tests. Adaptive schemes using previous viral load measurements to inform future monitoring significantly decreased the number of viral load tests without markedly increasing the number of months of undetected failure. The best adaptive monitoring scheme resulted in a 67% reduction in viral load measurements, while increasing the months of undetected failure by <20%. CONCLUSIONS: Adaptive viral load monitoring based on previous viral load measurements may be optimal for maintaining patient care while reducing costs, allowing more patients to be treated and monitored. Future empirical studies to evaluate differentiated monitoring are warranted.

Hepatitis E Virus Seroprevalence and Correlates of Anti-HEV IgG Antibodies in the Rakai District, Uganda.

A cross-sectional study was conducted of 500 human immunodeficiency virus (HIV)-infected adults frequency matched on age, sex, and community to 500 HIV-uninfected individuals in the Rakai District, Uganda to evaluate seroprevalence of anti-hepatitis E virus (HEV) IgG antibodies. HEV seroprevalence was 47%, and 1 HIV-infected individual was actively infected with a genotype 3 virus. Using modified Poisson regression, male sex (prevalence ratios [PR] = 1.247; 95% confidence interval [CI], 1.071-1.450) and chronic hepatitis B virus infection (PR = 1.377; 95% CI, 1.090-1.738) were associated with HEV seroprevalence. HIV infection status (PR = 0.973; 95% CI, 0.852-1.111) was not associated with HEV seroprevalence. These data suggest there is a large burden of prior exposure to HEV in rural Uganda.

Sexual risk behaviors following circumcision among HIV-positive men in Rakai, Uganda.

OBJECTIVE: To determine whether circumcision of HIV-positive men is associated with increased subsequent sexual risk behaviors which may place their female partners at risk. METHODS: Newly circumcised and uncircumcised HIV-positive men in the Rakai Community Cohort Study were followed from baseline (July 2013-January 2015) to determine trend in sexual risk behaviors and association of circumcision with subsequent sexual risk behaviors at follow up (February 2015-September 2016). Risk behaviors included sexual activity, alcohol before sex, transactional sex, multiple sex partners, casual sex partners, and inconsistent condom use with casual partners. The association was evaluated using modified Poisson regression, and sensitivity analyses were performed after multiple imputation with chained equations for missing data. RESULTS: We identified 538 eligible men, of whom 113(21.0%) were circumcised at baseline and 425(79.0%) were uncircumcised. Men in fishing communities were more likely to be circumcised (p = 0.032) as well as those exposed to targeted HIV messaging (p < 0.001). Overall, 188(34.9%) men were lost to follow up and most were uncircumcised (p = 0.020). Among those followed up, behaviors remained largely unchanged with no differences by circumcision status. Transactional sex appeared to be associated with circumcision in unadjusted analyses (PR = 1.58, 95%CI = 1.01,2.48; p = 0.045, p = 0.05) and adjusted analyses (adj.PR = 1.54, 95%CI = 1.06,2.23; p = 0.022). However, the association was no longer significant in sensitivity analyses after accounting for loss to follow up (adj.PR = 1.43, 95%CI = 0.98,2.08; p = 0.066). No association with circumcision was observed for other sexual risk behaviors. CONCLUSION: We found no association between circumcision of HIV-positive men and subsequent sexual risk behavior.

Rates of switching to second-line antiretroviral therapy and impact of delayed switching on immunologic, virologic, and mortality outcomes among HIV-infected adults with virologic failure in Rakai, Uganda.

BACKGROUND: Switch from first to second-line ART is recommended by WHO for patients with virologic failure. Delays in switching may contribute to accumulated drug resistance, advanced immunosuppression, increased morbidity and mortality. The 3rd 90' of UNAIDS 90:90:90 targets 90% viral suppression for persons on ART. We evaluated the rate of switching to second-line antiretroviral therapy (ART), and the impact of delayed switching on immunologic, virologic, and mortality outcomes in the Rakai Health Sciences Program (RHSP) Clinical Cohort Study which started providing ART in 2004 and implemented 6 monthly routine virologic monitoring beginning in 2005. METHODS: Retrospective cohort study of HIV-infected adults on first-line ART who had two consecutive viral loads (VLs) >1000 copies/ml after 6 months on ART between June 2004 and June 2011 was studied for switching to second-line ART. Immunologic decline after virologic failure was defined as decrease in CD4 count of ≥50 cells/ul and virologic increase was defined as increase of 0.5 log 10 copies/ml. Competing risk models were used to summarize rates of switching to second-line ART while cox proportional hazard marginal structural models were used to assess the risk of virologic increase or immunologic decline associated with delay to switch first line ART failing patients. RESULTS: The cumulative incidence of switching at 6, 12, and 24 months following virologic failure were 30.2%, 44.6%, and 65.0%, respectively. The switching rate was increased with higher VL at the time of virologic failure; compared to those with VLs ≤ 5000 copies/ml, patients with VLs = 5001-10,000 copies/ml had an aHR = 1.81 (95% CI = 0.9-3.6), and patients with VLs > 10,000 copies/ml had an aHR = 3.38 (95%CI = 1.9-6.2). The switching rate was also increased with CD4 < 100 cells/ul at ART initiation, compared to those with CD4 ≥ 100 cells/ul (aHR = 2.30, 95% CI = 1.5-3.6). Mortality in patients not switched to second-line ART was 11.9%, compared to 1.2% for those who switched (p = 0.009). Patients switched after 12 months of of virologic failure were more likely to experience CD4 decline and/or further VL increases. CONCLUSIONS: Intervention strategies that aid clinicians to promptly switch patients to second-line ART as soon as virologic failure on 1st line ART is confirmed should be prioritized.

HIV prevalence and uptake of HIV/AIDS services among youths (15-24 Years) in fishing and neighboring communities of Kasensero, Rakai District, South Western Uganda.

BACKGROUND: Although fishing communities have a significantly higher HIV prevalence than the general population, there is paucity of data on the burden of HIV and service utilization, particularly among the youth. We assessed the HIV prevalence and utilization of HIV prevention and treatment services among youth in Kasensero fishing community and the neighboring communities. METHOD: Data were derived from the Rakai Community Cohort Study (RCCS) surveys conducted between 2013 and 2014. The RCCS is a population-based household survey that collects data annually from individuals aged 15-49 years, resident in 48 communities in Rakai and neighboring districts in Uganda. For this analysis, socio-demographic, behavioral and HIV-related data were obtained for 792 individuals aged 15-24 years. We used logistic regression to conduct bivariate and multivariable analysis to determine the factors that are independently associated with HIV-positive status and their corresponding 95% confidence intervals. Data were analyzed using STATA version 13. RESULTS: Overall HIV prevalence was 19.7% (n = 155); higher in Kasensero (n = 141; 25.1%) and Gwanda (n = 8; 11%) than in Kyebe (n = 6; 3.9%), p < 0.001 and among females (n = 112; 26.0%) than males (n = 43; 12.0%), p < 0.001. Uptake of HIV testing was high in both HIV-positive (n = 136; 89.5%) and HIV-negative youth (n = 435; 92%). Consistent condom use was virtually non-existent in HIV-positive youth (n = 1; 0.6%) compared to HIV-negative youth (n = 20; 4.2%). Only 22.4% (n = 34) of the HIV-positive youth were receiving antiretroviral therapy (ART) in 2013-2014; higher in the HIV-positive females (n = 31; 28.4%) than HIV-positive males (n = 03; 6.7%). Slightly more than half of males (n = 134; 53.8%) reported that they were circumcised; the proportion of circumcised youth was higher among HIV-negative males (n = 122; 58%) than HIV-positive males (n = 12; 27.9%). Factors significantly associated with HIV-positive status included living in Kasensero landing site (adjusted Odds Ratio [aOR] = 5.0; 95%CI: 2.22-13.01) and reporting one (aOR = 5.0; 95%CI: 1.33-15.80) or 2+ sexual partners in the past 12 months (aOR = 11.0; 95% CI; 3.04-36.72). CONCLUSION: The prevalence of HIV is high especially among young females and in landing site communities than in the peripheral communities. Uptake of HIV prevention and treatment services is very low. There is an urgent need for youth-friendly services in these communities.

HIV acquisition is associated with increased antimicrobial peptides and reduced HIV neutralizing IgA in the foreskin prepuce of uncircumcised men.

BACKGROUND: The foreskin is the site of most HIV acquisition in uncircumcised heterosexual men. Although HIV-exposed, seronegative (HESN) uncircumcised men demonstrate HIV-neutralizing IgA and increased antimicrobial peptides (AMPs) in the foreskin prepuce, no prospective studies have examined the mucosal immune correlates of HIV acquisition. METHODS: To assess the association of foreskin immune parameters with HIV acquisition, antimicrobial peptides and IgA with the capacity to neutralize a primary clade C HIV strain were quantified by blinded investigators, using sub-preputial swabs collected longitudinally during a randomized trial of male circumcision for HIV prevention in Rakai, Uganda. RESULTS: Participants were 99 men who acquired HIV (cases) and 109 randomly selected controls who remained HIV seronegative. At enrollment, 44.4% of cases vs. 69.7% of controls demonstrated IgA neutralization (adjusted OR = 0.31; 95% CI, 0.16-0.61). IgA neutralization was detected in 38.7% of cases and 70.7% of controls at the last seronegative case visit prior to HIV acquisition and the comparable control visit (adjusted OR 0.21; 95% CI, 0.11-0.39). Levels of the α-defensins and secretory leukocyte protease inhibitor (SLPI) were over ten-fold higher in the foreskin prepuce of cases who acquired HIV, both at enrollment (mean 4.43 vs. 3.03 and 5.98 vs. 4.61 log(n) pg/mL, P = 0.005 and 0.009, respectively), and at the last seronegative visit (mean 4.81 vs. 3.15 and 6.46 vs. 5.20 log(n) pg/mL, P = 0.0002 and 0.013). CONCLUSIONS: This prospective, blinded analysis is the first to assess the immune correlates of HIV acquisition in the foreskin. HIV-neutralizing IgA, previously associated with the HESN phenotype, was a biomarker of HIV protection, but other HESN associations correlated with increased HIV acquisition. This emphasizes the importance of prospective epidemiological studies or in vitro tissue studies to define the impact of mucosal parameters on HIV risk.

Association of Medical Male Circumcision and Antiretroviral Therapy Scale-up With Community HIV Incidence in Rakai, Uganda.

IMPORTANCE: Medical male circumcision (MMC) and antiretroviral therapy (ART) are proven HIV prevention interventions, but there are limited data on the population-level effect of scale-up of these interventions in sub-Saharan Africa. Such evaluation is important for planning and resource allocation. OBJECTIVE: To examine whether increasing community MMC and ART coverage was associated with reduced community HIV incidence in Rakai District, Uganda. DESIGN, SETTING, AND PARTICIPANTS: Using person-level data from population-based surveys conducted from 1999 through 2013 in 45 rural Rakai communities, community-level ART and MMC coverage, sociodemographics, sexual behaviors, and HIV prevalence and incidence were estimated in 3 periods: prior to the availability of ART and MMC (1999-2004), during early availability of ART and MMC (2004-2007), and during mature program scale-up (2007-2013). EXPOSURES: Community MMC coverage in males and ART coverage in HIV-positive persons of the opposite sex based on self-reported MMC status and ART use. MAIN OUTCOMES AND MEASURES: Adjusted incidence rate ratios (IRRs) for sex-specific community HIV incidence estimated using multivariable Poisson regression with generalized estimating equations. RESULTS: From 1999 through 2013, 44,688 persons participated in 1 or more surveys (mean age at the first survey, 24.6 years [range, 15-49]; female, 56.5%; mean survey participation rate, 92.6% [95% CI, 92.4%-92.7%]). Median community MMC coverage increased from 19% to 39%, and median community ART coverage rose from 0% to 21% in males and from 0% to 26% in females. Median community HIV incidence declined from 1.25 to 0.84 per 100 person-years in males, and from 1.25 to 0.99 per 100 person-years in females. Among males, each 10% increase in community MMC coverage was associated with an adjusted IRR of 0.87 (95% CI, 0.82-0.93). Comparing communities with MMC coverage more than 40% (mean male community incidence, 1.03 per 100 person-years) with communities with coverage of 10% or less (mean male incidence, 1.69 per 100 person-years), the adjusted IRR was 0.61 (95% CI, 0.43-0.88). For each 10% increase in female self-reported ART coverage, there was no significant reduction in male HIV incidence (adjusted IRR, 0.95 [95% CI, 0.81-1.13]). Comparing communities with female ART coverage more than 20% (mean male incidence, 0.87 per 100 person-years) to communities with female ART coverage of 20% or less (mean male incidence, 1.17 per 100 person-years), the adjusted IRR was 0.77 (95% CI, 0.61-0.98). Neither MMC nor male ART coverage was associated with lower female community HIV incidence. CONCLUSIONS AND RELEVANCE: In Rakai, Uganda, increasing community MMC and female ART coverage was associated with lower community HIV incidence in males. If similar associations are found elsewhere, this would support further scale-up of MMC and ART for HIV prevention in sub-Saharan Africa.

The role of viral introductions in sustaining community-based HIV epidemics in rural Uganda: evidence from spatial clustering, phylogenetics, and egocentric transmission models.

BACKGROUND: It is often assumed that local sexual networks play a dominant role in HIV spread in sub-Saharan Africa. The aim of this study was to determine the extent to which continued HIV transmission in rural communities--home to two-thirds of the African population--is driven by intra-community sexual networks versus viral introductions from outside of communities. METHODS AND FINDINGS: We analyzed the spatial dynamics of HIV transmission in rural Rakai District, Uganda, using data from a cohort of 14,594 individuals within 46 communities. We applied spatial clustering statistics, viral phylogenetics, and probabilistic transmission models to quantify the relative contribution of viral introductions into communities versus community- and household-based transmission to HIV incidence. Individuals living in households with HIV-incident (n = 189) or HIV-prevalent (n = 1,597) persons were 3.2 (95% CI: 2.7-3.7) times more likely to be HIV infected themselves compared to the population in general, but spatial clustering outside of households was relatively weak and was confined to distances <500 m. Phylogenetic analyses of gag and env genes suggest that chains of transmission frequently cross community boundaries. A total of 95 phylogenetic clusters were identified, of which 44% (42/95) were two individuals sharing a household. Among the remaining clusters, 72% (38/53) crossed community boundaries. Using the locations of self-reported sexual partners, we estimate that 39% (95% CI: 34%-42%) of new viral transmissions occur within stable household partnerships, and that among those infected by extra-household sexual partners, 62% (95% CI: 55%-70%) are infected by sexual partners from outside their community. These results rely on the representativeness of the sample and the quality of self-reported partnership data and may not reflect HIV transmission patterns outside of Rakai. CONCLUSIONS: Our findings suggest that HIV introductions into communities are common and account for a significant proportion of new HIV infections acquired outside of households in rural Uganda, though the extent to which this is true elsewhere in Africa remains unknown. Our results also suggest that HIV prevention efforts should be implemented at spatial scales broader than the community and should target key populations likely responsible for introductions into communities.

Male circumcision and Mycoplasma genitalium infection in female partners: a randomised trial in Rakai, Uganda.

OBJECTIVE: Previous randomised trial data have demonstrated that male circumcision reduces Mycoplasma genitalium prevalence in men. We assessed whether male circumcision also reduces M genitalium infection in female partners of circumcised men. METHODS: HIV-negative men were enrolled and randomised to either male circumcision or control. Female partners of male trial participants from the intervention (n=437) and control (n=394) arms provided interview information and self-collected vaginal swabs that were tested for M genitalium by APTIMA transcription-mediated amplification-based assay. Prevalence risk ratios (PRR) and 95% CI of M genitalium prevalence in intervention versus control group were estimated using Poisson regression. Analysis was by intention-to-treat. An as-treated analysis was conducted to account for study-group crossovers. RESULTS: Male and female partner enrolment sociodemographic characteristics, sexual behaviours, and symptoms of sexually transmitted infections were similar between study arms. Female M genitalium prevalence at year 2 was 3.2% (14/437) in the intervention arm and 3.6% (14/394) in the control arm (PRR=0.90, 95% CI 0.43 to 1.89, p=0.78). In an as-treated analysis, the prevalence of M genitalium was 3.4% in female partners of circumcised men and 3.3% in female partners of uncircumcised men (PRR=1.01, 95% CI 0.48 to 2.12, p=0.97). CONCLUSIONS: Contrary to findings in men, male circumcision did not affect M genitalium infection in female partners.

Longitudinal patterns in indeterminate HIV rapid antibody test results: a population-based, prospective cohort study.

Rapid HIV tests are critical to HIV surveillance and universal testing and treatment programs. We assessed longitudinal patterns in indeterminate HIV rapid test results in an African population-based cohort. Prospective HIV rapid antibody test results, defined by two parallel rapid tests, among participants aged 15-49 years from three survey rounds of the Rakai Community Cohort Study, Uganda, from 2013 to 2018, were assessed. An indeterminate result was defined as any weak positive result or when one test was negative and the other was positive. A total of 31,405 participants contributed 54,459 person-visits, with 15,713 participants contributing multiple visits and 7,351 participants contributing 3 visits. The prevalence of indeterminate results was 2.7% (1,490/54,469). Of the participants with multiple visits who initially tested indeterminate (n = 591), 40.4% were negative, 18.6% were positive, and 41.0% were indeterminate at the subsequent visit. Of the participants with two consecutive indeterminate results who had a third visit (n = 67), 20.9% were negative, 9.0% were positive, and 70.2% remained indeterminate. Compared to a prior negative result, a prior indeterminate result was strongly associated with a subsequent indeterminate result [adjusted prevalence ratio, 23.0 (95% CI = 20.0-26.5)]. Compared to men, women were more likely to test indeterminate than negative [adjusted odds ratio, 2.3 (95% CI = 2.0-2.6)]. Indeterminate rapid HIV test results are highly correlated within an individual and 0.6% of the population persistently tested indeterminate over the study period. A substantial fraction of people with an indeterminate result subsequently tested HIV positive at the next visit, underscoring the importance of follow-up HIV testing protocols.IMPORTANCERapid HIV tests are a critical tool for expanding HIV testing and treatment to end the HIV epidemic. The interpretation and management of indeterminate rapid HIV test results pose a unique challenge for connecting all people living with HIV to the necessary care and treatment. Indeterminate rapid HIV test results are characterized by any weak positive result or discordant results (when one test is negative and the other is positive). We systematically tested all participants of a Ugandan population-based, longitudinal cohort study regardless of prior test results or HIV status to quantify longitudinal patterns in rapid HIV test results. We found that a substantial fraction (>15%) of participants with indeterminate rapid test results subsequently tested positive upon follow-up testing at the next visit. Our findings demonstrate the importance of follow-up HIV testing protocols for indeterminate rapid HIV test results.

HIV epidemiologic trends among occupational groups in Rakai, Uganda: A population-based longitudinal study, 1999-2016.

Certain occupations have been associated with heightened risk of HIV acquisition and spread in sub-Saharan Africa, including female bar and restaurant work and male transportation work. However, data on changes in population prevalence of HIV infection and HIV incidence within occupations following mass scale-up of African HIV treatment and prevention programs is very limited. We evaluated prospective data collected between 1999 and 2016 from the Rakai Community Cohort Study, a longitudinal population-based study of 15- to 49-year-old persons in Uganda. Adjusted prevalence risk ratios for overall, treated, and untreated, prevalent HIV infection, and incidence rate ratios for HIV incidence with 95% confidence intervals were estimated using Poisson regression to assess changes in HIV outcomes by occupation. Analyses were stratified by gender. There were 33,866 participants, including 19,113 (56%) women. Overall, HIV seroprevalence declined in most occupational subgroups among men, but increased or remained mostly stable among women. In contrast, prevalence of untreated HIV substantially declined between 1999 and 2016 in most occupations, irrespective of gender, including by 70% among men (12.3 to 4.2%; adjPRR = 0.30; 95%CI:0.23-0.41) and by 78% among women (14.7 to 4.0%; adjPRR = 0.22; 95%CI:0.18-0.27) working in agriculture, the most common self-reported primary occupation. Exceptions included men working in transportation. HIV incidence similarly declined in most occupations, but there were no reductions in incidence among female bar and restaurant workers, women working in local crafts, or men working in transportation. In summary, untreated HIV infection and HIV incidence have declined within most occupational groups in Uganda. However, women working in bars/restaurants and local crafts and men working in transportation continue to have a relatively high burden of untreated HIV and HIV incidence, and as such, should be considered priority populations for HIV programming.

Temporal dynamics and drivers of durable HIV viral load suppression and persistent high- and low-level viraemia during Universal Test and Treat scale-up in Uganda: a population-based study.

INTRODUCTION: Population-level data on durable HIV viral load suppression (VLS) following the implementation of Universal Test and Treat (UTT) in Africa are limited. We assessed trends in durable VLS and viraemia among persons living with HIV in 40 Ugandan communities during the UTT scale-up. METHODS: In 2015-2020, we measured VLS (<200 RNA copies/ml) among participants in the Rakai Community Cohort Study, a longitudinal population-based HIV surveillance cohort in southern Uganda. Persons with unsuppressed viral loads were characterized as having low-level (200-999 copies/ml) or high-level (≥1000 copies/ml) viraemia. Individual virologic outcomes were assessed over two consecutive RCCS survey visits (i.e. visit-pairs; ∼18-month visit intervals) and classified as durable VLS (<200 copies/ml at both visits), new/renewed VLS (<200 copies/ml at follow-up only), viral rebound (<200 copies/ml at initial visit only) or persistent viraemia (≥200 copies/ml at both visits). Population prevalence of each outcome was assessed over calendar time. Community-level prevalence and individual-level predictors of persistent high-level viraemia were also assessed using multivariable Poisson regression with generalized estimating equations. RESULTS: Overall, 3080 participants contributed 4604 visit-pairs over three survey rounds. Most visit-pairs (72.4%) exhibited durable VLS, with few (2.5%) experiencing viral rebound. Among those with any viraemia at the initial visit (23.5%, n = 1083), 46.9% remained viraemic through follow-up, 91.3% of which was high-level viraemia. One-fifth (20.8%) of visit-pairs exhibiting persistent high-level viraemia self-reported antiretroviral therapy (ART) use for ≥12 months. Prevalence of persistent high-level viraemia varied substantially across communities and was significantly elevated among young persons aged 15-29 years (vs. 40- to 49-year-olds; adjusted risk ratio [adjRR] = 2.96; 95% confidence interval [95% CI]: 2.21-3.96), males (vs. females; adjRR = 2.40, 95% CI: 1.87-3.07), persons reporting inconsistent condom use with non-marital/casual partners (vs. persons with marital/permanent partners only; adjRR = 1.38, 95% CI: 1.10-1.74) and persons reporting hazardous alcohol use (adjRR = 1.09, 95% CI: 1.03-1.16). The prevalence of persistent high-level viraemia was highest among males <30 years (32.0%). CONCLUSIONS: Following universal ART provision, most persons living with HIV in south-central Uganda are durably suppressed. Among persons exhibiting any viraemia, nearly half exhibited high-level viraemia for ≥12 months and reported higher-risk behaviours associated with onward HIV transmission. Intensified efforts linking individuals to HIV treatment services could accelerate momentum towards HIV epidemic control.

Implications of rapid population growth on survey design and HIV estimates in the Rakai Community Cohort Study (RCCS), Uganda.

OBJECTIVE: Since rapid population growth challenges longitudinal population-based HIV cohorts in Africa to maintain coverage of their target populations, this study evaluated whether the exclusion of some residents due to growing population size biases key HIV metrics like prevalence and population-level viremia. DESIGN, SETTING AND PARTICIPANTS: Data were obtained from the Rakai Community Cohort Study (RCCS) in south central Uganda, an open population-based cohort which began excluding some residents of newly constructed household structures within its surveillance boundaries in 2008. The study includes adults aged 15-49 years who were censused from 2019 to 2020. MEASURES: We fit ensemble machine learning models to RCCS census and survey data to predict HIV seroprevalence and viremia (prevalence of those with viral load >1000 copies/mL) in the excluded population and evaluated whether their inclusion would change overall estimates. RESULTS: Of the 24 729 census-eligible residents, 2920 (12%) residents were excluded from the RCCS because they were living in new households. The predicted seroprevalence for these excluded residents was 10.8% (95% CI: 9.6% to 11.8%)-somewhat lower than 11.7% (95% CI: 11.2% to 12.3%) in the observed sample. Predicted seroprevalence for younger excluded residents aged 15-24 years was 4.9% (95% CI: 3.6% to 6.1%)-significantly higher than that in the observed sample for the same age group (2.6% (95% CI: 2.2% to 3.1%)), while predicted seroprevalence for older excluded residents aged 25-49 years was 15.0% (95% CI: 13.3% to 16.4%)-significantly lower than their counterparts in the observed sample (17.2% (95% CI: 16.4% to 18.1%)). Over all ages, the predicted prevalence of viremia in excluded residents (3.7% (95% CI: 3.0% to 4.5%)) was significantly higher than that in the observed sample (1.7% (95% CI: 1.5% to 1.9%)), resulting in a higher overall population-level viremia estimate of 2.1% (95% CI: 1.8% to 2.4%). CONCLUSIONS: Exclusion of residents in new households may modestly bias HIV viremia estimates and some age-specific seroprevalence estimates in the RCCS. Overall, HIV seroprevalence estimates were not significantly affected.

A Moving Target: Impacts of Lowering Viral Load Suppression Cutpoints on Progress Towards HIV Epidemic Control Goals.

Redefining viral load suppression (VLS) using lower cutpoints could impact progress towards the UNAIDS 95-95-95 targets. We assessed impacts of lowering the VLS cutpoint on achieving the 95-95-95 VLS target in the Rakai Community Cohort Study. Population VLS fell from 86% to 84% and 76%, respectively, after lowering VLS cutpoints from <1,000 to <200 and <50 copies/mL. The fraction of viremic persons increased by 17% after lowering the VLS cutpoint from <1,000 to <200 copies/mL.

A moving target: impacts of lowering viral load suppression cutpoints on progress towards HIV epidemic control goals.

Redefining viral load suppression (VLS) using lower cutpoints could impact progress towards the United Nations Programme on HIV/AIDS 95-95-95 targets. We assessed impacts of lowering the VLS cutpoint on achieving the 'third 95' in the Rakai Community Cohort Study. Population VLS would fall from 86% to 84% and 76%, respectively, after lowering VLS cutpoints from <1000 to <200 and <50 copies/ml. The fraction of viremic persons increased by 17% after lowering the VLS cutpoint from <1000 to <200 copies/ml.

Temporal dynamics and drivers of durable HIV viral load suppression and persistent high- and low-level viremia during Universal Test and Treat scale-up in Uganda: a population-based study.

Introduction: Population-level data on durable HIV viral load suppression (VLS) following implementation of Universal Test and Treat (UTT) in Africa are limited. We assessed trends in durable VLS and viremia among persons living with HIV in 40 Ugandan communities during UTT scale-up. Methods: In 2015-2020, we measured VLS (defined as <200 RNA copies/mL) among participants in the Rakai Community Cohort Study, a longitudinal population-based HIV surveillance cohort in southern Uganda. Persons with unsuppressed viral loads were characterized as having low-level (200-999 copies/mL) or high-level (≥1,000 copies/mL) viremia. Individual virologic outcomes were assessed over two consecutive RCCS survey visits (i.e., visit-pairs; ∼18 month visit intervals) and classified as durable VLS (<200 copies/mL at both visits), new/renewed VLS (<200 copies/mL at follow-up only), viral rebound (<200 copies/mL at initial visit only), or persistent viremia (<200 copies/mL at neither visit). Population prevalence of each outcome was assessed over calendar time. Community-level prevalence and individual-level predictors of persistent high-level viremia were also assessed using multivariable Poisson regression with generalized estimating equations. Results: Overall, 3,080 participants contributed 4,604 visit-pairs over three survey rounds. Most visit-pairs (72.4%) exhibited durable VLS, with few (2.5%) experiencing viral rebound. Among those with viremia at the initial visit ( n =1,083), 46.9% maintained viremia through follow-up, 91.3% of which was high-level viremia. One-fifth (20.8%) of visit-pairs exhibiting persistent high-level viremia self-reported antiretroviral therapy (ART) use for ≥12 months. Prevalence of persistent high-level viremia varied substantially across communities and was significantly elevated among young persons aged 15-29 years (versus 40-49-year-olds; adjusted risk ratio [adjRR]=2.96; 95% confidence interval [95%CI]:2.21-3.96), men (versus women; adjRR=2.40, 95%CI:1.87-3.07), persons reporting inconsistent condom use with non-marital/casual partners (versus persons with marital/permanent partners only; adjRR=1.38, 95%CI:1.10-1.74), and persons exhibiting hazardous alcohol use (adjRR=1.09, 95%CI:1.03-1.16). The prevalence of persistent high-level viremia was highest among men <30 years (32.0%). Conclusions: Following universal ART provision, most persons living with HIV in south-central Uganda are durably suppressed. Among persons exhibiting viremia, nearly half maintain high-level viremia for ≥12 months and report higher-risk behaviors associated with onward HIV transmission. Enhanced linkage to HIV care and optimized treatment retention could accelerate momentum towards HIV epidemic control.