Community Viral Load Research Articles

Community SARS-CoV-2 Dynamics and Cycle Threshold Use to Enhance Public Health Surveillance in the Dominican Republic

To propose appropriate containment measures and optimize surveillance strategies, it is of utmost importance to understand the dynamics of SARS-CoV-2 transmission within different age groups and its symptomatic and asymptomatic presentations. This study aimed to understand the cycle-threshold (Ct) of SARS-CoV-2 within individuals attending hospital-based facilities in the Dominican Republic. A total of 3,309 saliva samples were analysed from 14 provinces, which yielded a positivity rate of 18.01% (n=596) across 24 sites. Saliva specimens and levels of viral RNA were quantified by RT-qPCR. Overall mean Ct values were 29.3 cycles and significantly correlated with community positivity rate (r=-0.034, p=0.04). There was no significant difference in mean Ct values between studied age groups [F (19, 30) = 0.65, p = 0.5] and no significant correlation between mean Ct by age groups and community positivity. When comparing asymptomatic and symptomatic patients by age groups, the patients between 5 and 17 years old demonstrated a statistically significant mean difference in Ct values with 27.5 and 32.4 cycles, respectively (t (14) = -2.3, p = 0.03). Results identified in this study demonstrate how understanding community viral load is crucial for optimal SARS-CoV-2 surveillance and should be evaluated in the context of transmissibility dynamics.

The Impact of Churn on HIV Outcomes in a Southern United States Clinical Cohort.

BackgroundPersons with human immunodeficiency virus (PWH) may experience a cycle of engaging and disengaging in care referred to as “churn.” While human immunodeficiency virus (HIV) churn is predicted to be more prevalent in the southern United States (US), it has not been well characterized in this region.MethodsWe conducted a retrospective cohort study involving PWH newly establishing care at a large urban clinic in Atlanta, Georgia, from 2012 to 2017, with follow-up data collected through 2019. The primary exposure was churn, defined as a ≥12-month gap between routine clinic visits or viral load (VL) measurements. We compared HIV metrics before and after churn and assessed the risk of future churn or loss to follow-up.ResultsOf 1303 PWH newly establishing care, 81.7% were male and 84.9% were Black; 200 (15.3%) experienced churn in 3.3 years of median follow-up time. The transmissible viremia (TV) rate increased from 28.6% prechurn to 66.2% postchurn (P < .0001). The 122 PWH having TV on reengagement had delayed time to subsequent viral suppression (adjusted hazard ratio, 0.59 [95% confidence interval {CI}, .48–.73]), and PWH returning to care contributed disproportionately to the community viral load (CVL) (proportion of CVL/proportion of patients, 1.96). Churn was not associated with an increased risk of subsequent churn (adjusted odds ratio [aOR], 1.53 [95% CI, .79–2.97]) or loss to follow-up (aOR, 1.04 [95% CI, .60–1.79]).ConclusionsThe rate of churn in a southern US clinic was high, and those who experienced churn had increased TV at reentry and disproportionately contributed to the CVL and likely contributing to ongoing HIV transmission.

Modeling DREAMS impact: trends in new HIV diagnoses among women attending antenatal care clinics in DREAMS countries.

To understand the impact of United States President's Emergency Plan for AIDS Relief (PEPFAR's) DREAMS (Determined, Resilient, Empowered, AIDS-Free, Mentored, and Safe) Partnership on new HIV diagnoses among women in antenatal care (ANC) settings in 10 African countries from 2015 to 2020. We modeled spatiotemporal changes in new HIV diagnoses among women in ANC settings using PEPFAR data. Statistical tests were performed in R to compare differences in new diagnoses rates between DREAMS and non-DREAMS subnational units (SNUs) and to explore predictors of new diagnoses declines within DREAMS SNUs. We used a predictive geospatial model to forecast the rate of new diagnoses for each time period in a 5 km grid cell (n = 861 SNUs). Linear model analyses were conducted using predictor variables: urbanicity, DREAMS geographic footprint, 'layering' proxy, and community-level male viral load suppression. New HIV diagnoses in ANC from 2015 to 2020 declined in nearly all SNUs. 'Always' DREAMS SNUs reported declines of 45% while 'Never' DREAMS SNUs reported a decline of only 37% (F = 8.1, 1 and 829 DF, P < 0.01). Within Always DREAMS SNUs, greater declines were seen in areas with a higher number of minimum services in their DREAMS primary package (t = 2.77, P < 0.01). New HIV diagnoses among women are declining in both DREAMS and non-DREAMS SNUs; mirroring HIV incidence decreases and reflecting increasing community viral load suppression and voluntary male medical circumcision rates. DREAMS programming may have contributed to accelerated declines of new HIV diagnoses in DREAMS SNUs compared with non-DREAMS SNUs. Increased progress is needed to further reduce the disparities between adolescent girls and young women (AGYW) and young men to achieve epidemic control.

Sharp decline in rates of community respiratory viral detection among patients at the National Institutes of Health Clinical Center during the coronavirus disease 2019 (COVID-19) pandemic.

To analyze the frequency and rates of community respiratory virus infections detected in patients at the National Institutes of Health Clinical Center (NIHCC) between January 2015 and March 2021, comparing the trends before and during the coronavirus disease 2019 (COVID-19) pandemic. We conducted a retrospective study comparing frequency and rates of community respiratory viruses detected in NIHCC patients between January 2015 and March 2021. Test results from nasopharyngeal swabs and washes, bronchoalveolar lavages, and bronchial washes were included in this study. Results from viral-challenge studies and repeated positives were excluded. A quantitative data analysis was completed using cross tabulations. Comparisons were performed using mixed models, applying the Dunnett correction for multiplicity. Frequency of all respiratory pathogens declined from an annual range of 0.88%-1.97% between January 2015 and March 2020 to 0.29% between April 2020 and March 2021. Individual viral pathogens declined sharply in frequency during the same period, with no cases of influenza A/B orparainfluenza and 1 case of respiratory syncytial virus (RSV). Rhino/enterovirusdetection continued, but with a substantially lower frequency of 4.27% between April 2020 and March 2021, compared with an annual range of 8.65%-18.28% between January 2015 and March 2020. The decrease in viral respiratory infections detected in NIHCC patients during the pandemic was likely due to the layered COVID-19 prevention and mitigation measures implemented in the community and the hospital. Hospitals should consider continuing the use of nonpharmaceutical interventions in the future to prevent nosocomial transmission of respiratory viruses during times of high community viral load.

Predicting the Risk of Human Immunodeficiency Virus Type 1 (HIV-1) Acquisition in Rural South Africa Using Geospatial Data.

BackgroundAccurate human immunodeficiency virus (HIV) risk assessment can guide optimal HIV prevention. We evaluated the performance of risk prediction models incorporating geospatial measures.MethodsWe developed and validated HIV risk prediction models in a population-based cohort in South Africa. Individual-level covariates included demographic and sexual behavior measures, and geospatial covariates included community HIV prevalence and viral load estimates. We trained models on 2012–2015 data using LASSO Cox models and validated predictions in 2016–2019 data. We compared full models to simpler models restricted to only individual-level covariates or only age and geospatial covariates. We compared the spatial distribution of predicted risk to that of high incidence areas (≥ 3/100 person-years).ResultsOur analysis included 19 556 individuals contributing 44 871 person-years and 1308 seroconversions. Incidence among the highest predicted risk quintile using the full model was 6.6/100 person-years (women) and 2.8/100 person-years (men). Models using only age group and geospatial covariates had similar performance (women: AUROC = 0.65, men: AUROC = 0.71) to the full models (women: AUROC = 0.68, men: AUROC = 0.72). Geospatial models more accurately identified high incidence regions than individual-level models; 20% of the study area with the highest predicted risk accounted for 60% of the high incidence areas when using geospatial models but only 13% using models with only individual-level covariates.ConclusionsGeospatial models with no individual measures other than age group predicted HIV risk nearly as well as models that included detailed behavioral data. Geospatial models may help guide HIV prevention efforts to individuals and geographic areas at highest risk.

Community transmission and viral load kinetics of the SARS-CoV-2 delta (B.1.617.2) variant in vaccinated and unvaccinated individuals in the UK: a prospective, longitudinal, cohort study

SummaryBackgroundThe SARS-CoV-2 delta (B.1.617.2) variant is highly transmissible and spreading globally, including in populations with high vaccination rates. We aimed to investigate transmission and viral load kinetics in vaccinated and unvaccinated individuals with mild delta variant infection in the community.MethodsBetween Sept 13, 2020, and Sept 15, 2021, 602 community contacts (identified via the UK contract-tracing system) of 471 UK COVID-19 index cases were recruited to the Assessment of Transmission and Contagiousness of COVID-19 in Contacts cohort study and contributed 8145 upper respiratory tract samples from daily sampling for up to 20 days. Household and non-household exposed contacts aged 5 years or older were eligible for recruitment if they could provide informed consent and agree to self-swabbing of the upper respiratory tract. We analysed transmission risk by vaccination status for 231 contacts exposed to 162 epidemiologically linked delta variant-infected index cases. We compared viral load trajectories from fully vaccinated individuals with delta infection (n=29) with unvaccinated individuals with delta (n=16), alpha (B.1.1.7; n=39), and pre-alpha (n=49) infections. Primary outcomes for the epidemiological analysis were to assess the secondary attack rate (SAR) in household contacts stratified by contact vaccination status and the index cases’ vaccination status. Primary outcomes for the viral load kinetics analysis were to detect differences in the peak viral load, viral growth rate, and viral decline rate between participants according to SARS-CoV-2 variant and vaccination status.FindingsThe SAR in household contacts exposed to the delta variant was 25% (95% CI 18–33) for fully vaccinated individuals compared with 38% (24–53) in unvaccinated individuals. The median time between second vaccine dose and study recruitment in fully vaccinated contacts was longer for infected individuals (median 101 days [IQR 74–120]) than for uninfected individuals (64 days [32–97], p=0·001). SAR among household contacts exposed to fully vaccinated index cases was similar to household contacts exposed to unvaccinated index cases (25% [95% CI 15–35] for vaccinated vs 23% [15–31] for unvaccinated). 12 (39%) of 31 infections in fully vaccinated household contacts arose from fully vaccinated epidemiologically linked index cases, further confirmed by genomic and virological analysis in three index case–contact pairs. Although peak viral load did not differ by vaccination status or variant type, it increased modestly with age (difference of 0·39 [95% credible interval –0·03 to 0·79] in peak log10 viral load per mL between those aged 10 years and 50 years). Fully vaccinated individuals with delta variant infection had a faster (posterior probability >0·84) mean rate of viral load decline (0·95 log10 copies per mL per day) than did unvaccinated individuals with pre-alpha (0·69), alpha (0·82), or delta (0·79) variant infections. Within individuals, faster viral load growth was correlated with higher peak viral load (correlation 0·42 [95% credible interval 0·13 to 0·65]) and slower decline (–0·44 [–0·67 to –0·18]).InterpretationVaccination reduces the risk of delta variant infection and accelerates viral clearance. Nonetheless, fully vaccinated individuals with breakthrough infections have peak viral load similar to unvaccinated cases and can efficiently transmit infection in household settings, including to fully vaccinated contacts. Host–virus interactions early in infection may shape the entire viral trajectory.FundingNational Institute for Health Research.

Population HIV viral load metrics for community health.

Evidence linking HIV-1 RNA viral load and downstream HIV incidence is strong on both an individual and population level. The risk of HIV acquisition is higher from people with HIV who have high viral load levels compared with low viral load levels. In North American settings, rates of HIV incidence have tracked with viral suppression levels in people who have been diagnosed with HIV (ie, community viral load).1 Universal HIV test-and-treat trials done in sub-Saharan Africa between 2012 and 2018 show that expanding universal HIV testing and antiretroviral therapy (ART) delivery can substantially reduce population viral load, with concomitant reductions in HIV incidence.

Lessons from two SARS-CoV-2 waves in South Africa

Lessons from two SARS-CoV-2 waves in South Africa

Trends in COVID-19-related in-hospital mortality: lessons learned from nationwide samples

Trends in COVID-19-related in-hospital mortality: lessons learned from nationwide samples

Community Transmission and Viral Load Kinetics of SARS-CoV-2 Delta (B.1.617.2)Variant in Vaccinated and Unvaccinated Individuals

Background: The SARS-CoV-2 Delta variant is highly transmissible and spreading globally but a detailed understanding of community transmission risks in highly vaccinated populations is lacking.Methods: Between September 2020 and August 2021, we recruited 510 community contacts of 422 UK COVID-19 cases to a cohort study. A total of 7194 upper respiratory tract (URT) samples were tested from sequential daily sampling of participants for up to 20 days. We analysed transmission risk by vaccination status for 139 contacts exposed to the Delta variant. We compared viral load (VL) trajectories from fully-vaccinated cases of Delta infection (n=19) with unvaccinated Delta (n=10), Alpha (n=39) and pre-Alpha (n=49) infections.Findings: The household secondary attack rate for fully-vaccinated contacts exposed to Delta was 19.7% (95%CI:11.6-31.3%), compared with 35.7% (95%CI:16.4-61.2%) in the unvaccinated. One third of infections in Delta-exposed contacts arose from fully-vaccinated index cases and one half of infected contacts were also fully-vaccinated. Seven transmission events between fully vaccinated index-contact pairs occurred. Genomic analysis confirmed transmission pathways between fully-vaccinated individuals within three households. Peak VL was similar in vaccinated and unvaccinated individuals with Delta variant infection but vaccinated Delta cases saw significantly faster VL decline than unvaccinated Alpha or Delta cases. Within infected individuals, faster VL growth was correlated with higher peak VL and slower decline.Interpretation: Although vaccination reduces the risk of Delta infection and causes some changes to viral kinetics, fully-vaccinated individuals with breakthrough infections have peak URT VL similar to unvaccinated cases and can efficiently transmit infection in household settings, including to fully vaccinated contacts.Funding: National Institute for Health Research (Award:NIHR200927)Declaration of Interest: The authors declare no relevant conflicts.Ethical Approval: The study was approved by the Health Research Authority (Research Ethics Committee reference: 20/NW/0231).

Hepatitis C Virus Incidence in a Cohort in Medication-Assisted Treatment for Opioid Use Disorder in New York City.

Hepatitis C virus (HCV) incidence has increased in the worsening opioid epidemic. We examined the HCV preventive efficacy of medication-assisted treatment (MAT), and geographic variation in HCV community viral load (CVL) and its association with HCV incidence. HCV incidence was directly measured in an open cohort of patients in a MAT program in New York City between 1 January 2013 and 31 December 2016. Area-level HCV CVL was calculated. Associations of individual-level factors, and of HCV CVL, with HCV incidence were examined in separate analyses. Among 8352 patients, HCV prevalence was 48.7%. Among 2535 patients seronegative at first antibody test, HCV incidence was 2.25/100 person-years of observation (PYO). Incidence was 6.70/100 PYO among those reporting main drug use by injection. Female gender, drug injection, and lower MAT retention were significantly associated with higher incidence rate ratios. Female gender, drug injection, and methadone doses <60 mg were independently associated with shorter time to HCV seroconversion. HCV CVLs varied significantly by geographic area. HCV incidence was higher among those with lower MAT retention and was lower among those receiving higher methadone doses, suggesting the need to ensure high MAT retention, adequate doses, and increased HCV prevention and treatment engagement. HCV CVLs vary geographically and merit further study as predictors of HCV incidence.

Hepatitis C Virus (HCV) Care Continuum Outcomes and HCV Community Viral Loads Among Patients in an Opioid Treatment Program.

Hepatitis C virus (HCV) remains endemic among people who use drugs (PWUD). Measures of HCV community viral load (CVL) and HCV care continuum outcomes may be valuable for ascertaining unmet treatment need and for HCV surveillance and control. Data from patients in an opioid treatment program during 2013-2016 were used to (1) identify proportions of antibody and viral load (VL) tested, linked-to-care, and treated, in 2013-2014 and 2015-2016, and pre- and postimplementation of qualitative reflex VL testing; (2) calculate engaged-in-care HCV CVL and "documented" and "estimated" unmet treatment need; and (3) examine factors associated with linkage-to-HCV-care. Among 11 267 patients, proportions of HCV antibody tested (52.5% in 2013-2014 vs 73.3% in 2015-2016), linked-to-HCV-care (15.7% vs 51.8%), and treated (12.0% vs 44.7%) all increased significantly. Hispanic ethnicity was associated with less linkage-to-care, and Manhattan residence was associated with improved linkage-to-care. The overall engaged-in-care HCV CVL was 4 351 079 copies/mL (standard deviation = 7 149 888); local HCV CVLs varied by subgroup and geography. Documented and estimated unmet treatment need decreased but remained high. After qualitative reflex VL testing was implemented, care continuum outcomes improved, but gaps remained. High rates of unmet treatment need suggest that control of the HCV epidemic among PWUD will require expansion of HCV treatment coverage.

From Hospital to the Community: Redesigning the Human Immunodeficiency Virus (HIV) Clinical Service Model to Respond to an Outbreak of HIV Among People Who Inject Drugs.

An outbreak of human immunodeficiency virus (HIV) among people who inject drugs in Glasgow, Scotland started in 2014. We describe 156 cases over 5 years and evaluate the impact of clinical interventions using virological and phylogenetic analysis. We established (1) HIV services within homeless health facilities, including outreach nurses, and (2) antiretroviral therapy (ART) via community pharmacies. Implementation of the new model reduced time to ART initiation from 264 to 23 days and increased community viral load suppression rates to 86%. Phylogenetic analysis demonstrated that 2019 diagnoses were concentrated within a single network. Traditional HIV care models require adaptation for this highly complex population.

Community viral load and hepatitis C virus infection: Community viral load measures to aid public health treatment efforts and program evaluation

BackgroundHepatitis C virus (HCV) infection is the most prevalent blood-borne infection and causes more deaths than any other infectious disease in the US. Incident HCV infection in the US increased nearly 300 % between 2010 and 2015, Community viral load (CVL) measures have been developed for HIV to measure both transmission risk and treatment engagement in programs or areas. ObjectiveThis paper presents a systematic review exploring the published literature on CVL constructs applied to HCV epidemiology and proposes novel CVL measures for HCV. Study design and settingA systematic review was conducted of electronic databases; the search sought to identify published literature on HCV which discussed or applied CVL measures to HCV epidemiology. Novel CVL measures were constructed to apply to HCV. ResultsNo reports examining quantitative measures of HCV CVL were identified. Using the HIV CVL literature and the specific characteristics of HCV epidemiology, five HCV CVL measures are proposed. Narrower measures focusing on those engaged-in-care may be useful for program evaluation and broader measures including undiagnosed people may be useful for surveillance of HCV transmission potential. ConclusionDespite their potential value, CVL constructs have not yet formally been developed and applied to HCV epidemiology. The CVL measures proposed here could serve as valuable HCV program and surveillance measures. There is a need for informative surveillance measures to enhance policy and public health responses to achieve HCV control. Further study of these proposed HCV CVL measures to HCV epidemiology is warranted.

1267. Contribution of Acute Infection to the Community Viral Load of an HIV Care Program

BackgroundIndividuals with acute HIV infection (AHI) are a priority for public health due to higher viral loads and greater risk of transmission. Despite potential clinical and public health benefits, rapid or immediate ART can be resource-intensive, with programmatic implications. We measured the contribution of AHI to our programs community viral load (VL) to inform our expanded testing and linkage to care program.MethodsWe calculated the contribution to the community VL for 3 HIV-positive groups from January 1, 2016 to September 1, 2018; (1) AHI (p24 antigen-positive, negative or indeterminate supplemental antibody testing), (2) new diagnoses (ND), and (3) existing diagnoses (ED). Persons who were AHI or ND were ART naïve at first VL. The contribution of each group to community VL was calculated at the first and second VL assays. Group contributions were characterized as (1) percentage of the total HIV-positive population, and (2) group contribution to community VL.Results217 persons tested positive for HIV and had an initial VL, and 69 persons linked to our program had a second VL. Time intervals between first and second VL measurements were similar between groups (Kruskal–Wallis P = 0.55). Initial VL medians were significantly different by group (Kruskal–Wallis P < 0.001), partly due to the large number of ED in care and virally suppressed ( <200 copies/mL) at first VL (n = 82). AHI contributed the fewest persons to the HIV-positive population (7.8%), but contributed the most to first VL (58.6%). ART reduced VL for all groups. The median time from diagnosis to treatment for AHI was 5.5 days (IQR 4–21). Due to both natural decay and ART, AHI contributed the least to total VL load at second assay (5.6%). Using previously published data on treated and untreated VL decay, a delay in ART of 15 days would resulted in an estimated VL of 17,721 copies/mL (95% confidence interval (537- 53,576) vs. the estimated VL with ART, 131 copies/mL (95% CI 5–294), a 135-fold increase in AHI VL.ConclusionPatients with AHI are small proportion of our cohort compared with ND and ED, but account for the greatest portion of our community VL. These data quantifies the benefit of rapid initiation of ART for AHI to reduce community VL, a priority for prevention efforts. Disclosures All authors: No reported disclosures.

The Impact of "Churn" on Plasma HIV Burden Within a Population Under Care.

BackgroundCross-sectional reporting of viral suppression rates within a population underestimates the community viral load (VL) burden. Longitudinal approaches, while addressing cumulative effects, may still underestimate viral burden if “churn” (movement in and out of care) is not incorporated. We examined the impact of churn on the cumulative community HIV viral burden.MethodsAll HIV+ patients followed in 2016–2017 at the Southern Alberta Clinic (Calgary, Canada) were categorized as follows: (1) in continuous care, (2) newly diagnosed, (3) diagnosed elsewhere transferring care, (4) returning to care, (5) lost-to-follow-up, (6) moved care elsewhere, or (7) died. Patient days were classified by VL as suppressed (≤200copies/ml), unsuppressed (>200 copies/ml), and transmittable (>1500 copies/ml).ResultsOf 1934 patients, 78.4% had suppressed VL; 21.4% had ≥1 unsuppressed VL, and 18.7% ≥1 transmittable VL. Of 1 276 507 total patient days in care, 92.1% were spent suppressed, 7.9% unsuppressed (101 459 days), and 6.4% (81 847 days) transmittable. 88.7% of category 1 patients had suppressed VL, 11.3% ≥1 unsuppressed VL, and 8.9% ever a transmittable VL. Of category 2 patients, 90% became suppressed on treatment (mean – 62 days). 38.5% of category 3 patients presented with a transmittable VL. Category 4 and 5 patients combined had high rates of unsuppressed (54.5%) and transmittable (51.2%) VL and, while representing only 6.2% of all patients, they accounted for 37.1% of unsuppressed and 41.5% of all transmittable days.ConclusionFocus on VL of patients continuously in care misses those with unsuppressed and transmittable VL in a community. Patients moving in and out of care pose an underappreciated risk for HIV transmissions.

PO 8549 ACHIEVING THE THIRD ‘90’ AMONG KEY POPULATIONS THROUGH A DIFFERENTIATED CARE MODEL

BackgroundPartners in Health and Development in Africa (PHDA) is an HIV/STI research centre that serves both female and male sex workers in Nairobi. PHDA offers HIV/STI care and treatment, and prevention services to approximately 27,400 female sex workers and 1600 men who have sex with men. Currently, the organisation has 2384 HIV-positive female and male sex workers who access HIV care and treatment services within PHDA. We realised HIV viral suppression of our clients was at 78%, and therefore we came up with a strategy to reach at least 90% viral suppression.MethodsPatients who were virally suppressed, had their scheduled clinic visits reduced to twice annually, while viraemic clients visited the facility at least twice a month for directly observed therapy of ARVs. Clients who were non-viraemic (champions) and willing to participate in support groups were selected through simple random sampling to join the viraemic clients support groups. The champions encouraged the viraemic peers on the importance of adhering to treatment to gain viral suppression and reduce time spent at the facilities. Challenges and successes were also shared. This was done for a minimum of three consecutive months and graduation done upon viral suppression.ResultsEighty-eight per cent (88%; 2117/2384) of the total positives were bled for viral loads within the year; 78.3% (1658/2117) had viral suppression and 459/2117 had viral loads (VL) above 1000 copies per ml of blood. After attending the joint support groups with documented good adherence for at least three consecutive months, clients were bled for a repeat VL count, of which 84% (386/459) had suppressed. This increased the overall viral suppression from 78.3% to 93.8%( 2044/2177). There was 73% risk of being viraemic if not attending a support group.ConclusionDifferentiated care clients can work with viraemic clients to increase community viral load suppression.

Sociobehavioral and community predictors of unsuppressed HIV viral load: multilevel results from a hyperendemic rural South African population.

Extensive antiretroviral therapy scale-up is expected to prevent onward transmission of HIV by reducing the overall community viral load. Despite multiple studies about predictors of detectable viral load derived from clinical setting, to date, no study has established such predictors using a population-based viral load survey in a sub-Saharan African hyperendemic setting to inform interventions designed to halt HIV transmission. We used one of Africa's largest prospective cohorts in rural KwaZulu-Natal Province, South Africa, to establish the key sociodemographic, behavioral and community predictors of unsuppressed viral load at the population level. We collected 5454 viral load measurements from a population-based viral load survey of 3892 women living with HIV from a rural population during 2011, 2013 and 2014. Multilevel logistic regression models were fitted to examine the risk predictors of unsuppressed viral load. Among women living with HIV in this population, the prevalence of unsuppressed viral load was 69% in 2011, 58% in 2013 and 53% in 2014. Although time since HIV infection was associated with lower risk for virologic detection [adjusted odds ratio (aOR) = 0.91,0.87-0.94], young women (aOR = 2.59,1.47-4.55) with extensive external migration history (aOR = 1.25,1.02-1.54), greater number of sexual partners (aOR = 1.30,1.02-1.67), and longer history of residing in an HIV incidence hotspot community were more likely to experience unsuppressed viral load (aOR = 1.12,1.06-1.19). Young women, number of sexual partners, transiency and longer residence in an HIV hotspot community are important determinants of unsuppressed viral load in a hyperendemic rural African setting. To substantially reduce the persistently high transmission potential in these settings, targeted interventions to address these risk factors will be essential for both individual and population health gains.

Predictors of postpartum HIV care engagement for women enrolled in prevention of mother-to-child transmission (PMTCT) programs in Tanzania

ABSTRACTPrevention of mother-to-child transmission of HIV (PMTCT) is a foundational component of a comprehensive HIV treatment program. In addition to preventing vertical transmission to children, PMTCT is an important catch-point for universal test-and-treat strategies that can reduce community viral load and slow the epidemic. However, systematic reviews suggest that care engagement in PMTCT programs is sub-optimal. This study enrolled a cohort of 200 women initiating PMTCT in Kilimanjaro, Tanzania, and followed them to assess HIV care engagement and associated factors. Six months after delivery, 42/200 (21%) of participants were identified as having poor care engagement, defined as HIV RNA >200 copies/mL or, if viral load was unavailable, being lost-to-follow-up in the clinical records or self-reporting being out of care. In a multivariable risk factor analysis, younger women were more likely to have poor postpartum care engagement; with each year of age, women were 7% less likely to have poor care engagement (aRR: 0.93; 95% CI: 0.89, 0.98). Additionally, women who had told at least one person about their HIV status were 47% less likely to have poor care engagement (aRR: .53; 95% CI: 0.29, 0.97). Among women who entered antenatal care with an established HIV diagnosis, those who were pregnant for the first time had increased risk of poor care engagement (aRR 4.16; 95% CI 1.53, 11.28). The findings suggest that care engagement remains a concern in PMTCT programs, and must be addressed to realize the goals of PMTCT. Comprehensive counseling on HIV disclosure, along with community-based stigma reduction programs to provide a supportive environment for people living with HIV, are crucial to address barriers to care engagement and support long-term treatment. Women presenting to antenatal care with an established HIV status require support for care engagement during the crucial period surrounding childbirth, particularly those pregnant for the first time.

Associations between sexual partner number and HIV risk behaviors: implications for HIV prevention efforts in a Treatment as Prevention (TasP) environment

ABSTRACTPrevious research indicates that gay and bisexual men (GBM) have significantly more sexual partners than same-aged heterosexual men and women. As a result, some HIV intervention programs have focused on partner reduction. However, new research findings question the relevance of sexual partner number as a sexual risk measure for GBM given Treatment as Prevention (TasP) programs and new seroadaptive strategies which have led to lower GBM community viral load and new HIV prevention behaviors. To assess if sexual partner number continues to remain an important measure of sexual risk for GBM living in a city that actively promotes TasP as provincial policy, we analysed cross-sectional data from 719 GBM recruited through respondent-driven sampling in Vancouver, Canada. Multivariable negative binomial regression analysis showed that partner number was significantly associated with previously identified HIV risk factors including condomless anal intercourse with serodiscordant and/or unknown serostatus partners, using sex toys, attending group sex events, receiving money for sex, and sex drug use. These results indicate that sexual partner number remains an important proximate HIV risk measure. However, more nuanced measures of HIV treatment status and greater understanding of the possible causes of increased partner number among GBM are needed.