Waning of 2-Dose BNT162b2 and mRNA-1273 Vaccine Effectiveness Against Symptomatic SARS-CoV-2 Infection Accounting for Depletion-of-Susceptibles Bias.

Concerns about the duration of protection conferred by coronavirus disease 2019 (COVID-19) vaccines have arisen in postlicensure evaluations. "Depletion of susceptibles," a bias driven by differential accrual of infection among vaccinated and unvaccinated individuals, may obscure vaccine effectiveness (VE) estimates, hindering interpretation. We enrolled California residents who received molecular SARS-CoV-2 tests in a matched, test-negative design, case-control study to estimate VE of mRNA-based COVID-19 vaccines between February 23 and December 5, 2021. We analyzed waning protection following 2 vaccine doses using conditional logistic regression models. Additionally, we used data from a population-based serological study to adjust for "depletion-of-susceptibles" bias and estimated VE for 3 doses, by time since second dose receipt. Pooled VE of BNT162b2 and mRNA-1273 against symptomatic SARS-CoV-2 infection was 91.3% (95% confidence interval (CI): 83.8, 95.4) at 14 days after second-dose receipt and declined to 50.8% (95% CI: 19.7, 69.8) at 7 months. Adjusting for depletion-of-susceptibles bias, we estimated VE of 53.2% (95% CI: 23.6, 71.2) at 7 months after primary mRNA vaccination series. A booster dose of BN162b2 or mRNA-1273 increased VE to 95.0% (95% CI: 82.8, 98.6). These findings confirm that observed waning of protection is not attributable to epidemiologic bias and support ongoing efforts to administer additional vaccine doses to mitigate burden of COVID-19.

Prevention of Coronavirus Disease 2019 (COVID-19) by mRNA-Based Vaccines Within the General Population of California.

BACKGROUND: Estimates of coronavirus disease 2019 (COVID-19) vaccine effectiveness under real-world conditions, and understanding of barriers to uptake, are necessary to inform vaccine rollout. METHODS: We enrolled cases (testing positive) and controls (testing negative) from among the population whose SARS-CoV-2 molecular diagnostic test results from 24 February to 29 April 2021 were reported to the California Department of Public Health. Participants were matched on age, sex, and geographic region. We assessed participants' self-reported history of mRNA-based COVID-19 vaccine receipt (BNT162b2 and mRNA-1273). Participants were considered fully vaccinated 2 weeks after second dose receipt. Among unvaccinated participants, we assessed willingness to receive vaccination. We measured vaccine effectiveness (VE) via the matched odds ratio of prior vaccination, comparing cases with controls. RESULTS: We enrolled 1023 eligible participants aged ≥18 years. Among 525 cases, 71 (13.5%) received BNT162b2 or mRNA-1273; 20 (3.8%) were fully vaccinated with either product. Among 498 controls, 185 (37.1%) received BNT162b2 or mRNA-1273; 86 (16.3%) were fully vaccinated with either product. Two weeks after second dose receipt, VE was 87.0% (95% confidence interval: 68.6-94.6%) and 86.2% (68.4-93.9%) for BNT162b2 and mRNA-1273, respectively. Fully vaccinated participants receiving either product experienced 91.3% (79.3-96.3%) and 68.3% (27.9-85.7%) VE against symptomatic and asymptomatic infection, respectively. Among unvaccinated participants, 42.4% (159/375) residing in rural regions and 23.8% (67/281) residing in urban regions reported hesitancy to receive COVID-19 vaccination. CONCLUSIONS: Authorized mRNA-based vaccines are effective at reducing documented SARS-CoV-2 infections within the general population of California. Vaccine hesitancy presents a barrier to reaching coverage levels needed for herd immunity.

Predictors of Severe Acute Respiratory Syndrome Coronavirus 2 Infection Following High-Risk Exposure.

BACKGROUND: Non-pharmaceutical interventions (NPIs) are recommended for COVID-19 prevention. However, the effectiveness of NPIs in preventing SARS-CoV-2 transmission remains poorly quantified. METHODS: We conducted a test-negative design case-control study enrolling cases (testing positive for SARS-CoV-2) and controls (testing negative) with molecular SARS-CoV-2 diagnostic test results reported to California Department of Public Health between 24 February-12 November, 2021. We used conditional logistic regression to estimate adjusted odds ratios (aORs) of case status among participants who reported contact with an individual known or suspected to have been infected with SARS-CoV-2 ("high-risk exposure") ≤14 days before testing. RESULTS: 751 of 1448 cases (52%) and 255 of 1443 controls (18%) reported high-risk exposures ≤14 days before testing. Adjusted odds of case status were 3.02-fold (95% confidence interval: 1.75-5.22) higher when high-risk exposures occurred with household members (vs. other contacts), 2.10-fold (1.05-4.21) higher when exposures occurred indoors (vs. outdoors only), and 2.15-fold (1.27-3.67) higher when exposures lasted ≥3 hours (vs. shorter durations) among unvaccinated and partially-vaccinated individuals; excess risk associated with such exposures was mitigated among fully-vaccinated individuals. Cases were less likely than controls to report mask usage during high-risk exposures (aOR = 0.50 [0.29-0.85]). The adjusted odds of case status was lower for fully-vaccinated (aOR = 0.25 [0.15-0.43]) participants compared to unvaccinated participants. Benefits of mask usage were greatest among unvaccinated and partially-vaccinated participants, and in interactions involving non-household contacts or interactions occurring without physical contact. CONCLUSIONS: NPIs reduced the likelihood of SARS-CoV-2 infection following high-risk exposure. Vaccine effectiveness was substantial for partially and fully vaccinated persons.

Severe Acute Respiratory Syndrome Coronavirus 2 and Respiratory Virus Sentinel Surveillance, California, USA, May 10, 2020-June 12, 2021.

State and local health departments established the California Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and Respiratory Virus Sentinel Surveillance System to conduct enhanced surveillance for SARS-CoV-2 and other respiratory pathogens at sentinel outpatient testing sites in 10 counties throughout California, USA. We describe results obtained during May 10, 2020‒June 12, 2021, and compare persons with positive and negative SARS-CoV-2 PCR results by using Poisson regression. We detected SARS-CoV-2 in 1,696 (19.6%) of 8,662 specimens. Among 7,851 specimens tested by respiratory panel, rhinovirus/enterovirus was detected in 906 (11.5%) specimens and other respiratory pathogens in 136 (1.7%) specimens. We also detected 23 co-infections with SARS-CoV-2 and another pathogen. SARS-CoV-2 positivity was associated with male participants, an age of 35-49 years, Latino race/ethnicity, obesity, and work in transportation occupations. Sentinel surveillance can provide useful virologic and epidemiologic data to supplement other disease monitoring activities and might become increasingly useful as routine testing decreases.

Effectiveness of Face Mask or Respirator Use in Indoor Public Settings for Prevention of SARS-CoV-2 Infection - California, February-December 2021.

The use of face masks or respirators (N95/KN95) is recommended to reduce transmission of SARS-CoV-2, the virus that causes COVID-19 (1). Well-fitting face masks and respirators effectively filter virus-sized particles in laboratory conditions (2,3), though few studies have assessed their real-world effectiveness in preventing acquisition of SARS-CoV-2 infection (4). A test-negative design case-control study enrolled randomly selected California residents who had received a test result for SARS-CoV-2 during February 18-December 1, 2021. Face mask or respirator use was assessed among 652 case-participants (residents who had received positive test results for SARS-CoV-2) and 1,176 matched control-participants (residents who had received negative test results for SARS-CoV-2) who self-reported being in indoor public settings during the 2 weeks preceding testing and who reported no known contact with anyone with confirmed or suspected SARS-CoV-2 infection during this time. Always using a face mask or respirator in indoor public settings was associated with lower adjusted odds of a positive test result compared with never wearing a face mask or respirator in these settings (adjusted odds ratio [aOR] = 0.44; 95% CI = 0.24-0.82). Among 534 participants who specified the type of face covering they typically used, wearing N95/KN95 respirators (aOR = 0.17; 95% CI = 0.05-0.64) or surgical masks (aOR = 0.34; 95% CI = 0.13-0.90) was associated with significantly lower adjusted odds of a positive test result compared with not wearing any face mask or respirator. These findings reinforce that in addition to being up to date with recommended COVID-19 vaccinations, consistently wearing a face mask or respirator in indoor public settings reduces the risk of acquiring SARS-CoV-2 infection. Using a respirator offers the highest level of personal protection against acquiring infection, although it is most important to wear a mask or respirator that is comfortable and can be used consistently.

Pilot Implementation of a User-Driven, Web-Based Application Designed to Improve Sexual Health Knowledge and Communication Among Young Zambians: Mixed Methods Study.

BACKGROUND: Digital health interventions show promise in improving the uptake of HIV services among adolescents and young people aged 15 to 24 years in sub-Saharan Africa. OBJECTIVE: This study aimed to pilot-test a theory-based, empirically grounded web-based application designed to increase condom-related knowledge, sexual and reproductive health (SRH) communication, and healthier choices among young Zambians. METHODS: We conducted a pre-post quasi-experimental evaluation of the user-driven Be in the Know Zambia (BITKZ) web application using web-based surveys and in-depth interviews (IDIs) on the phone. We enrolled participants using social media advertisements. Our final analysis set comprised 46.04% (749/1627) of participants in the intervention group (which received the BITKZ link) and 53.96% (878/1627) of participants in the comparison group (no intervention). We collected survey data at study enrollment (baseline) and 5 weeks after the first enrollment in each group. Approximately 85% (637/749) of BITKZ users completed a user survey, of whom 9.3% (59/637) participated in IDIs. We calculated the time interfacing with BITKZ using the application log files. We conducted descriptive analyses to describe baseline characteristics and the user experience. At the endline, we assessed association using a t test and adjusted logistic regression for binary outcomes and ordinal regression for ordered outcomes, conditioning on age, sex, marital status, and employment status. We used adjusted average treatment effects (aATE) to assess the effects of BITKZ intervention. We conducted rapid matrix analyses of IDI transcripts in Microsoft Excel, sorting the data by theme, gender, and experience rating. RESULTS: Users rated BITKZ highly (excellent: 352/609, 57.8%; good: 218/609, 35.8%). At the endline, the intervention group had a higher level of knowledge related to condoms (adjusted odds ratio [aOR]: 1.35, 95% CI 1.06-1.69) and on wearing condoms correctly (aOR: 1.23, 95% CI 1.02-1.49). Those who had full-time employment had increased odds of knowing how to wear condoms correctly (aOR: 1.67, 95% CI 1.06-2.63) compared with those who reported being unemployed, as did men when compared with women (aOR: 1.92, 95% CI 1.59-2.31). Those in the intervention group were more likely to score higher for intention to test for sexually transmitted infections (STIs; aATE 0.21; P=.01) and HIV (aATE 0.32; P=.05), as well as for resisting peer pressure (aATE 2.64; P=.02). IDIs corroborated increased knowledge on correct condom use among men and female condoms among women, awareness of STIs and testing, and resistance to peer pressure. Interviewees provided examples of more open SRH communication with partners and peers and of considering, adopting, and influencing others to adopt healthier behaviors. CONCLUSIONS: Despite the high baseline awareness of SRH among Zambian adolescents and young people with internet access, BITKZ provided modest gains in condom-related knowledge, resistance to peer pressure, and intention to test for STIs and HIV.

Novel Longitudinal Methods for Assessing Retention in Care: a Synthetic Review.

PURPOSE OF REVIEW: Retention in care is both dynamic and longitudinal in nature, but current approaches to retention often reduce these complex histories into cross-sectional metrics that obscure the nuanced experiences of patients receiving HIV care. In this review, we discuss contemporary approaches to assessing retention in care that captures its dynamic nature and the methodological and data considerations to do so. RECENT FINDINGS: Enhancing retention measurements either through patient tracing or "big data" approaches (including probabilistic matching) to link databases from different sources can be used to assess longitudinal retention from the perspective of the patient when they transition in and out of care and access care at different facilities. Novel longitudinal analytic approaches such as multi-state and group-based trajectory analyses are designed specifically for assessing metrics that can change over time such as retention in care. Multi-state analyses capture the transitions individuals make in between different retention states over time and provide a comprehensive depiction of longitudinal population-level outcomes. Group-based trajectory analyses can identify patient subgroups that follow distinctive retention trajectories over time and highlight the heterogeneity of retention patterns across the population. Emerging approaches to longitudinally measure retention in care provide nuanced assessments that reveal unique insights into different care gaps at different time points over an individuals' treatment. These methods help meet the needs of the current scientific agenda for retention and reveal important opportunities for developing more tailored interventions that target the varied care challenges patients may face over the course of lifelong treatment.

Longitudinal Care Cascade Outcomes Among People Eligible for Antiretroviral Therapy Who Are Newly Linking to Care in Zambia: A Multistate Analysis.

BACKGROUND: Retention in human immunodeficiency virus (HIV) care is dynamic, with patients frequently transitioning in and out of care. Analytical approaches (eg, survival analyses) commonly used to assess HIV care cascade outcomes fail to capture such transitions and therefore incompletely represent care outcomes over time. METHODS: We analyzed antiretroviral therapy (ART)-eligible adults newly linking to care at 64 clinics in Zambia between 1 April 2014 and 31 July 2015. We used electronic medical record data and supplemented these with updated care outcomes ascertained by tracing a multistage random sample of patients lost to follow-up (LTFU, >90 days late for last appointment). We performed multistate analyses, incorporating weights from sampling, to estimate the prevalence of 9 care states over time since linkage with respect to ART initiation, retention in care, transfers, and mortality. RESULTS: In sum, 23 227 patients (58% female; median age 34 years [interquartile range 28-41]) were ART-eligible at enrollment. At 1 year, 75.2% had initiated ART and were in care: 61.8% were continuously retained, 6.1% had reengaged after LTFU, and 7.3% had transferred. Also, 10.1% were LTFU within 7 days of enrollment, and 15.2% were LTFU at 1 year (6.7% prior to ART). One year after LTFU, 51.6% of those LTFU prior to ART remained out of care compared to 30.2% of those LTFU after initiating ART. Overall, 6.9% of patients had died by 1 year with 3.0% dying prior to ART. CONCLUSION: Multistate analyses provide more complete assessments of longitudinal HIV cascade outcomes and reveal treatment gaps at distinct timepoints in care that will still need to be addressed even with universal treatment.

Participation in adherence clubs and on-time drug pickup among HIV-infected adults in Zambia: A matched-pair cluster randomized trial.

BACKGROUND: Current models of HIV service delivery, with frequent facility visits, have led to facility congestion, patient and healthcare provider dissatisfaction, and suboptimal quality of services and retention in care. The Zambian urban adherence club (AC) is a health service innovation designed to improve on-time drug pickup and retention in HIV care through off-hours facility access and pharmacist-led group drug distribution. Similar models of differentiated service delivery (DSD) have shown promise in South Africa, but observational analyses of these models are prone to bias and confounding. We sought to evaluate the effectiveness and implementation of ACs in Zambia using a more rigorous study design. METHODS AND FINDINGS: Using a matched-pair cluster randomized study design (ClinicalTrials.gov: NCT02776254), 10 clinics were randomized to intervention (5 clinics) or control (5 clinics). At each clinic, between May 19 and October 27, 2016, a systematic random sample was assessed for eligibility (HIV+, age ≥ 14 years, on ART >6 months, not acutely ill, CD4 count not <200 cells/mm3) and willingness to participate in an AC. Clinical and antiretroviral drug pickup data were obtained through the existing electronic medical record. AC meeting attendance data were collected at intervention facilities prospectively through October 28, 2017. The primary outcome was time to first late drug pickup (>7 days late). Intervention effect was estimated using unadjusted Kaplan-Meier survival curves and a Cox proportional hazards model to derive an adjusted hazard ratio (aHR). Medication possession ratio (MPR) and implementation outcomes (adoption, acceptability, appropriateness, feasibility, and fidelity) were additionally evaluated as secondary outcomes. Baseline characteristics were similar between 571 intervention and 489 control participants with respect to median age (42 versus 41 years), sex (62% versus 66% female), median time since ART initiation (4.8 versus 5.0 years), median CD4 count at study enrollment (506 versus 533 cells/mm3), and baseline retention (53% versus 55% with at least 1 late drug pickup in previous 12 months). The rate of late drug pickup was lower in intervention participants compared to control participants (aHR 0.26, 95% CI 0.15-0.45, p < 0.001). Median MPR was 100% in intervention participants compared to 96% in control participants (p < 0.001). Although 18% (683/3,734) of AC group meeting visits were missed, on-time drug pickup (within 7 days) still occurred in 51% (350/683) of these missed visits through alternate means (use of buddy pickup or early return to the facility). Qualitative evaluation suggests that the intervention was acceptable to both patients and providers. While patients embraced the convenience and patient-centeredness of the model, preference for traditional adherence counseling and need for greater human resources influenced intervention appropriateness and feasibility from the provider perspective. The main limitations of this study were the small number of clusters, lack of viral load data, and relatively short follow-up period. CONCLUSIONS: ACs were found to be an effective model of service delivery for reducing late ART drug pickup among HIV-infected adults in Zambia. Drug pickup outside of group meetings was relatively common and underscores the need for DSD models to be flexible and patient-centered if they are to be effective. TRIAL REGISTRATION: ClinicalTrials.gov NCT02776254.

Mortality estimates by age and sex among persons living with HIV after ART initiation in Zambia using electronic medical records supplemented with tracing a sample of lost patients: A cohort study.

BACKGROUND: Men in sub-Saharan Africa have lower engagement and retention in HIV services compared to women, which may result in differential survival. However, the true magnitude of difference in HIV-related mortality between men and women receiving antiretroviral therapy (ART) is incompletely characterized. METHODS AND FINDINGS: We evaluated HIV-positive adults ≥18 years old newly initiating ART in 4 Zambian provinces (Eastern, Lusaka, Southern, and Western). In addition to mortality data obtained from routine electronic medical records, we intensively traced a random sample of patients lost to follow-up (LTFU) and incorporated tracing outcomes through inverse probability weights. Sex-specific mortality rates and rate differences were determined using Poisson regression. Parametric g-computation was used to estimate adjusted mortality rates by sex and age. The study included 49,129 adults newly initiated on ART between August 2013 and July 2015; overall, the median age among patients was 35 years, the median baseline CD4 count was 262 cells/µl, and 37.2% were men. Men comprised a smaller proportion of individuals starting ART (37.2% versus 62.8%), tended to be older (median age 37 versus 33 years), and tended to have lower CD4 counts (median 220 versus 289 cells/µl) at the time of ART initiation compared to women. The overall rate of mortality among men was 10.3 (95% CI 8.2-12.4) deaths/100 person-years (PYs), compared to 5.5 (95% CI 4.3-6.8) deaths/100 PYs among women (difference +4.7 [95% CI 2.3-7.2] deaths/100 PYs; p < 0.001). Compared to women in the same age groups, men's mortality rates were particularly elevated among those <30 years old (+6.7 deaths/100 PYs difference), those attending rural health centers (+9.4 deaths/100 PYs difference), those who had an initial CD4 count < 100 cells/µl (+9.2 deaths/100 PYs difference), and those who were unmarried (+8.0 deaths/100 PYs difference). After adjustment for potential confounders and mediators including CD4 count, a substantially higher mortality rate was predicted among men <30 years old compared to women of the same age, while women ≥50 years old had a mortality rate similar to that of age-matched men, but considerably higher than that predicted among young women (<30 years old). No clinically significant differences were evident with respect to rates of facility transfer or care disengagement between men and women. The main study limitations were the inability to successfully ascertain outcomes in all patients selected for tracing and missing clinical and laboratory data due to the use of medical records. CONCLUSIONS: In this study, we found that among HIV-positive adults newly initiating ART, mortality among men exceeded mortality among women; disparities were most pronounced among young patients. Older women, however, also experienced high mortality. Specific interventions for men and older women at highest mortality risk are needed to improve HIV treatment outcomes.

Estimating the real-world effects of expanding antiretroviral treatment eligibility: Evidence from a regression discontinuity analysis in Zambia.

BACKGROUND: Although randomized trials have established the clinical efficacy of treating all persons living with HIV (PLWHs), expanding treatment eligibility in the real world may have additional behavioral effects (e.g., changes in retention) or lead to unintended consequences (e.g., crowding out sicker patients owing to increased patient volume). Using a regression discontinuity design, we sought to assess the effects of a previous change to Zambia's HIV treatment guidelines increasing the threshold for treatment eligibility from 350 to 500 cells/µL to anticipate effects of current global efforts to treat all PLWHs. METHODS AND FINDINGS: We analyzed antiretroviral therapy (ART)-naïve adults who newly enrolled in HIV care in a network of 64 clinics operated by the Zambian Ministry of Health and supported by the Centre for Infectious Disease Research in Zambia (CIDRZ). Patients were restricted to those enrolling in a narrow window around the April 1, 2014 change to Zambian HIV treatment guidelines that raised the CD4 threshold for treatment from 350 to 500 cells/µL (i.e., August 1, 2013, to November 1, 2014). Clinical and sociodemographic data were obtained from an electronic medical record system used in routine care. We used a regression discontinuity design to estimate the effects of this change in treatment eligibility on ART initiation within 3 months of enrollment, retention in care at 6 months (defined as clinic attendance between 3 and 9 months after enrollment), and a composite of both ART initiation by 3 months and retention in care at 6 months in all new enrollees. We also performed an instrumental variable (IV) analysis to quantify the effect of actually initiating ART because of this guideline change on retention. Overall, 34,857 ART-naïve patients (39.1% male, median age 34 years [IQR 28-41], median CD4 268 cells/µL [IQR 134-430]) newly enrolled in HIV care during this period; 23,036 were analyzed after excluding patients around the threshold to allow for clinic-to-clinic variations in actual guideline uptake. In all newly enrolling patients, expanding the CD4 threshold for treatment from 350 to 500 cells/µL was associated with a 13.6% absolute increase in ART initiation within 3 months of enrollment (95% CI, 11.1%-16.2%), a 4.1% absolute increase in retention at 6 months (95% CI, 1.6%-6.7%), and a 10.8% absolute increase in the percentage of patients who initiated ART by 3 months and were retained at six months (95% CI, 8.1%-13.5%). These effects were greatest in patients who would have become newly eligible for ART with the change in guidelines: a 43.7% increase in ART initiation by 3 months (95% CI, 37.5%-49.9%), 13.6% increase in retention at six months (95% CI, 7.3%-20.0%), and a 35.5% increase in the percentage of patients on ART at 3 months and still in care at 6 months [95% CI, 29.2%-41.9%). We did not observe decreases in ART initiation or retention in patients not directly targeted by the guideline change. An IV analysis found that initiating ART in response to the guideline change led to a 37.9% (95% CI, 28.8%-46.9%) absolute increase in retention in care. Limitations of this study include uncertain generalizability under newer models of care, lack of laboratory data (e.g., viral load), inability to account for earlier stages in the HIV care cascade (e.g., HIV testing and linkage), and potential for misclassification of eligibility status or outcome. CONCLUSIONS: In this study, guidelines raising the CD4 threshold for treatment from 350 to 500 cells/µL were associated with a rapid rise in ART initiation as well as enhanced retention among newly treatment-eligible patients, without negatively impacting patients with lower CD4 levels. These data suggest that health systems in Zambia and other high-prevalence settings could substantially enhance engagement even among those with high CD4 levels (i.e., above 500 cells/µL) by expanding treatment without undermining existing care standards.

Defining long COVID using a population-based SARS-CoV-2 survey in California.

BACKGROUND: More than four years after the start of the COVID-19 pandemic, understanding of SARS-CoV-2 burden and post-acute sequela of COVID (PASC), or long COVID, continues to evolve. However, prevalence estimates are disparate and uncertain. Leveraging survey responses from a large serosurveillance study, we assess prevalence estimates using five different long COVID definitions among California residents. METHODS: The California Department of Public Health (CDPH) conducted a cross-sectional survey that included questions about acute COVID-19 infection and recovery. A random selection of California households was invited to participate in a survey that included demographic information, clinical symptoms, and COVID-19 vaccination history. We assessed prevalence and predictors of long COVID among those previously testing positive for SARS-CoV-2 across different definitions using logistic regression. FINDINGS: A total of 2883 participants were included in this analysis; the majority identified as female (62.5 %), and the median age was 39 years (interquartile range: 17-55 years). We found a significant difference in long COVID prevalence across definitions with the highest prevalence observed when participants were asked about incomplete recovery (20.9 %, 95 % confidence interval [CI]: 19.4-22.5) and the lowest prevalence was associated with severe long COVID affecting an estimated 4.9 % (95 % CI 4.1-5.7) of the participant population. Individuals that completed the primary vaccination series had significantly lower prevalence of long COVID compared to those that did not receive COVID vaccination. INTERPRETATION: There were significant differences in the estimated prevalence of long COVID across different definitions. People who experience a severe initial COVID-19 infection should be considered at a higher probability for developing long COVID. FUNDING: Centers for Disease Control and Prevention - Epidemiology and Laboratory Capacity.

An exploration of multi-level factors affecting routine linkage to HIV care in Zambia's PEPFAR-supported treatment program in the treat all era.

Multiple steps from HIV diagnosis to treatment initiation and confirmed engagement with the health system are required for people living with HIV to establish full linkage to care in the modern treat all era. We undertook a qualitative study to gain an in-depth understanding of the impeding and enabling factors at each step of this linkage pathway. In-depth interviews were conducted with fifty-eight people living with HIV recruited from ten routine HIV care settings supported by the U.S. President's Emergency Plan for AIDS Relief (PEPFAR) in Lusaka, Zambia. Using a semi-structured interview guide informed by an established conceptual framework for linkage to care, questions explored the reasons behind late, missed, and early linkage into HIV treatment, as well as factors influencing the decision to silently transfer to a different clinic after an HIV diagnosis. We identified previously established and intersecting barriers of internal and external HIV-related stigma, concerns about ART side effects, substance use, uncertainties for the future, and a perceived lack of partner and social support that impeded linkage to care at every step of the linkage pathway. However, we also uncovered newer themes specific to the current test and treat era related to the rapidity of ART initiation and insufficient patient-centered post-test counseling that appeared to exacerbate these well-known barriers, including callous health workers and limited time to process a new HIV diagnosis before treatment. Long travel distance to the clinic where they were diagnosed was the most common reason for silently transferring to another clinic for treatment. On the other hand, individual resilience, quality counseling, patient-centered health workers, and a supportive and empathetic social network mitigated these barriers. These findings highlight potential areas for strengthening linkage to care and addressing early treatment interruption and silent transfer in the test and treat era in Zambia.

Mixed methods approach to examining the implementation experience of a phone-based survey for a SARS-CoV-2 test-negative case-control study in California.

OBJECTIVE: To describe the implementation of a test-negative design case-control study in California during the Coronavirus Disease 2019 (COVID-19) pandemic. STUDY DESIGN: Test-negative case-control study. METHODS: Between February 24, 2021 - February 24, 2022, a team of 34 interviewers called 38,470 Californians, enrolling 1,885 that tested positive for SARS-CoV-2 (cases) and 1,871 testing negative for SARS-CoV-2 (controls) for 20-minute telephone survey. We estimated adjusted odds ratios for answering the phone and consenting to participate using mixed effects logistic regression. We used a web-based anonymous survey to compile interviewer experiences. RESULTS: Cases had 1.29-fold (95% CI: 1.24-1.35) higher adjusted odds of answering the phone and 1.69-fold (1.56-1.83) higher adjusted odds of consenting to participate compared to controls. Calls placed from 4pm to 6pm had the highest adjusted odds of being answered. Some interviewers experienced mental wellness challenges interacting with participants with physical (e.g., food, shelter, etc.) and emotional (e.g., grief counseling) needs, and enduring verbal harassment from individuals called. CONCLUSIONS: Calls placed during afternoon hours may optimize response rate when enrolling controls to a case-control study during a public health emergency response. Proactive check-ins and continual collection of interviewer experience(s) and may help maintain mental wellbeing of investigation workforce. Remaining adaptive to the dynamic needs of the investigation team is critical to a successful study, especially in emergent public health crises, like that represented by the COVID-19 pandemic.

Programme science in action: lessons from an observational study of HIV prevention programming for key populations in Lusaka, Zambia.

INTRODUCTION: Optimizing uptake of pre-exposure prophylaxis (PrEP) for individuals at risk of HIV acquisition has been challenging despite clear scientific evidence and normative guidelines, particularly for key populations (KPs) such as men who have sex with men (MSM), female sex workers (FSWs), transgender (TG) people and persons who inject drugs (PWID). Applying an iterative Programme Science cycle, building on the effective programme coverage framework, we describe the approach used by the Centre for Infectious Disease Research in Zambia (CIDRZ) to scale up PrEP delivery and address inequities in PrEP access for KP in Lusaka, Zambia. METHODS: In 2019, CIDRZ partnered with 10 local KP civil society organizations (CSOs) and the Ministry of Health (MOH) to offer HIV services within KP-designated community safe spaces. KP CSO partners led KP mobilization, managed safe spaces and delivered peer support; MOH organized clinicians and clinical commodities; and CIDRZ provided technical oversight. In December 2021, we introduced a community-based intervention focused on PrEP delivery in venues where KP socialize. We collected routine programme data from September 2019 to June 2023 using programme-specific tools and the national electronic health record. We estimated the before-after effects of our intervention on PrEP uptake, continuation and equity for KP using descriptive statistics and interrupted time series regression, and used mixed-effects regression to estimate marginal probabilities of PrEP continuity. RESULTS: Most (25,658) of the 38,307 (67.0%) Key Population Investment Fund beneficiaries were reached with HIV prevention services at community-based venues. In total, 23,527 (61.4%) received HIV testing services, with 15,508 (65.9%) testing HIV negative and found PrEP eligible, and 15,241 (98.3%) initiating PrEP. Across all programme quarters and KP types, PrEP uptake was >90%. After introducing venue-based PrEP delivery, PrEP uptake (98.7% after vs. 96.5% before, p < 0.001) and the number of initiations (p = 0.014) increased significantly. The proportion of KP with ≥1 PrEP continuation visit within 6 months of initiation was unchanged post-intervention (46.7%, 95% confidence interval [CI]: 45.7%, 47.6%) versus pre-intervention (47.2%, 95% CI: 45.4%, 49.1%). CONCLUSIONS: Applying Programme Science principles, we demonstrate how decentralizing HIV prevention services to KP venues and safe spaces in partnership with KP CSOs enabled successful community-based PrEP delivery beyond the reach of traditional facility-based services.

The Social Construction of Aging Among a Clinic-Based Population and Their Healthcare Workers in Zambia.

Objectives: We sought to understand the social construction of aging in a clinic-based population, with and without HIV, to address gaps in care for older individuals living with HIV in Zambia. Methods: Our exploratory qualitative study included 36 in-depth interviews with clinic clients and four focus group discussions with 36 professional and lay healthcare workers providing services to the clients. We identified themes based on social construction theory. Results: At the individual level, aging was multidimensional, perceived both as an achievement in the HIV era and as a period of cognitive, physical, and economic decline. In social interactions, older individuals were often stereotyped and treated as helpless, poor, and "witches." Those living with HIV faced the additional stigma of being labeled as promiscuous. Some of the participants living without HIV refused to take daily medication for non-communicable diseases to avoid being mistaken for taking antiretroviral therapy for HIV. Older individuals wanted quality healthcare and family support to address the intersectional stigma of aging, poverty, and chronic illness. Conclusion: Multifaceted interventions are required to combat age-related prejudice, intersectional stigma, and discriminatory practices, particularly for people living with HIV.

Evaluating a multifaceted implementation strategy and package of evidence-based interventions based on WHO PEN for people living with HIV and cardiometabolic conditions in Lusaka, Zambia: protocol for the TASKPEN hybrid effectiveness-implementation stepped wedge cluster randomized trial.

BACKGROUND: Despite increasing morbidity and mortality from non-communicable diseases (NCD) globally, health systems in low- and middle-income countries (LMICs) have limited capacity to address these chronic conditions, particularly in sub-Saharan Africa (SSA). There is an urgent need, therefore, to respond to NCDs in SSA, beginning by applying lessons learned from the first global response to any chronic disease-HIV-to tackle the leading cardiometabolic killers of people living with HIV (PLHIV). We have developed a feasible and acceptable package of evidence-based interventions and a multi-faceted implementation strategy, known as "TASKPEN," that has been adapted to the Zambian setting to address hypertension, diabetes, and dyslipidemia. The TASKPEN multifaceted implementation strategy focuses on reorganizing service delivery for integrated HIV-NCD care and features task-shifting, practice facilitation, and leveraging HIV platforms for NCD care. We propose a hybrid type II effectiveness-implementation stepped-wedge cluster randomized trial to evaluate the effects of TASKPEN on clinical and implementation outcomes, including dual control of HIV and cardiometabolic NCDs, as well as quality of life, intervention reach, and cost-effectiveness. METHODS: The trial will be conducted in 12 urban health facilities in Lusaka, Zambia over a 30-month period. Clinical outcomes will be assessed via surveys with PLHIV accessing routine HIV services, and a prospective cohort of PLHIV with cardiometabolic comorbidities nested within the larger trial. We will also collect data using mixed methods, including in-depth interviews, questionnaires, focus group discussions, and structured observations, and estimate cost-effectiveness through time-and-motion studies and other costing methods, to understand implementation outcomes according to Proctor's Outcomes for Implementation Research, the Consolidated Framework for Implementation Research, and selected dimensions of RE-AIM. DISCUSSION: Findings from this study will be used to make discrete, actionable, and context-specific recommendations in Zambia and the region for integrating cardiometabolic NCD care into national HIV treatment programs. While the TASKPEN study focuses on cardiometabolic NCDs in PLHIV, the multifaceted implementation strategy studied will be relevant to other NCDs and to people without HIV. It is expected that the trial will generate new insights that enable delivery of high-quality integrated HIV-NCD care, which may improve cardiovascular morbidity and viral suppression for PLHIV in SSA. This study was registered at ClinicalTrials.gov (NCT05950919).

Estimating potential silent transfer using baseline viral load measures among people presenting as new to HIV care in Lusaka, Zambia: a cross-sectional study.

OBJECTIVES: To estimate potential silent transfer using baseline viral load measures among individuals presenting as new to HIV care in routine HIV clinical settings in Lusaka, Zambia. DESIGN: Cross-sectional study. SETTING: Two large, urban government-operated health facilities supported by the Centre for Infectious Disease Research in Zambia. PARTICIPANTS: A total of 248 participants with an incident positive HIV rapid test. OUTCOME MEASURES: The primary outcome measure was HIV viral suppression at baseline (i.e., potential silent transfer), defined as having a viral load ≤1000 RNA copies(c)/mL at the time of initiating HIV care. We also examined viral suppression at ≤60 c/mL. METHODS: We surveyed and measured baseline HIV viral load as part of the national recent infection testing algorithm among people living with HIV (PLWH) presenting as new to care. Using mixed effects Poisson regression, we identified characteristics among PLWH associated with potential silent transfer. RESULTS: Among the 248 PLWH included, 63% were women with median age of 30, and 66 (27% (66/248)) had viral suppression at ≤1000 c/mL and 53 (21% (53/248)) at ≤60 c/mL thresholds, respectively. Participants aged 40+ years had a significantly higher adjusted prevalence of potential silent transfer (adjusted prevalence ratio (aPR): 2.10; 95% CI: 2.08, 2.13) compared with participants aged 18-24 years. Participants reporting no formal education had a significantly higher adjusted prevalence of potential silent transfer (aPR: 1.63; 95% CI: 1.52, 1.75) compared with those completing primary education. Among 57 potential silent transfers who completed a survey, 44 (77%) indicated having tested positive previously at ≥1 of 38 clinics in Zambia. CONCLUSIONS: The high proportion of PLWH with potential silent transfer points to clinic shopping and/or co-enrolment at multiple care sites simultaneously, suggesting an opportunity to improve care continuity at the time of HIV care entry.

Provider perspectives on patient-centredness: participatory formative research and rapid analysis methods to inform the design and implementation of a facility-based HIV care improvement intervention in Zambia.

INTRODUCTION: Implementation of patient-centred care (PCC) practices in HIV treatment depends on healthcare workers' (HCWs) perceptions of the acceptability, appropriateness and feasibility of such practices (e.g. use of intentional, metric-driven activities to improve patient experiences). METHODS: We applied rapid, rigorous formative research methods to refine a PCC intervention for future trial. In 2018, we conducted focus group discussions (FGDs) with 46 HCWs purposefully selected from two pilot sites. We elicited HCW perceptions of HIV service delivery, HCW motivation and perceived value of patient experience measures intended to improve PCC. FGDs utilized participatory methods to understand HCW responses to patient-reported care engagement challenges and Scholl's PCC Framework principles (e.g. seeing a patient as a unique person), enablers (e.g. care coordination) and activities (e.g. patient involvement). Our rapid analysis used analytic memos, thematic analysis, research team debriefs and HCW feedback to inform time-sensitive trial implementation. RESULTS: While HCWs nearly universally identified with and supported principles of PCC in both facilities, they raised practical barriers given the practice environment. HCWs described motivation to help patients, attached value to seeing positive health outcomes and the importance of teamwork. However, HCWs reported challenges with enablers needed to deliver PCC. HCWs cited a work culture characterized by differential power dynamics between cadres and departments restricting HCW autonomy and resource access. Barriers included inflexibility in accommodating individual patient needs due to high patient volumes, limited human resources, laboratory capacity, infrastructure and skills translating patient perspectives into practice. HCW motivation was negatively influenced by encounters with "difficult patients," and feeling "unappreciated" by management, resulting in cognitive dissonance between HCW beliefs and behaviours. However, the enactment of PCC values also occurred. Results suggested that PCC interventions should reduce practice barriers, highlighting the value of mentors who could help HCWs dynamically engage with health system constraints, to facilitate PCC. CONCLUSIONS: While HCWs perceived PCC principles as acceptable, they did not think it universally appropriate or feasible given the practice environment. Participatory and rapid methods provided timely insight that PCC interventions must provide clear and effective systems enabling PCC activities by measuring and mitigating relational and organizational constraints amenable to change such as inter-cadre coordination.

Cross-sectional study to assess depression among healthcare workers in Lusaka, Zambia during the COVID-19 pandemic.

OBJECTIVES: We sought to assess depression among healthcare workers (HCWs) in the context of COVID-19 in Lusaka Province, Zambia. DESIGN: This cross-sectional study is nested within a larger study, the Person-Centred Public Health for HIV Treatment in Zambia (PCPH), a cluster-randomised trial to assess HIV care and outcomes. SETTING: The research was conducted in 24 government-run health facilities from 11 August to 15 October 2020 during the first wave of the COVID-19 pandemic in Lusaka, Zambia. PARTICIPANTS: We used convenience sampling to recruit HCW participants who were previously enrolled in the PCPH study, had more than 6 months' experience working at the facility and were voluntarily willing to participate. PRIMARY OUTCOME MEASURES: We implemented the well-validated 9-question Patient Health Questionnaire (PHQ-9) to assess HCW depression. We used mixed-effects, adjusted Poisson regression to estimate the marginal probability of HCWs experiencing depression that may warrant intervention (PHQ-9 score ≥5) by healthcare facility. RESULTS: We collected PHQ-9 survey responses from 713 professional and lay HCWs. Overall, 334 (46.8%, 95% CI 43.1%, 50.6%) HCWs recorded a PHQ-9 score ≥5, indicating the need for further assessment and potential intervention for depression. We identified significant heterogeneity across facilities and observed a greater proportion of HCWs with symptoms of depression in facilities providing COVID-19 testing and treatment services. CONCLUSIONS: Depression may be a concern for a large proportion of HCWs in Zambia. Further work to understand the magnitude and aetiologies of depression among HCWs in the public sector is needed to design effective prevention and treatment interventions to meet the needs for mental health support and to minimise poor health outcomes.