Publications by authors named "Joshua A Salomon"

225 Publications

Multimorbidity and mortality in an older, rural black South African population cohort with high prevalence of HIV findings from the HAALSI Study.

BMJ Open 2021 Sep 15;11(9):e047777. Epub 2021 Sep 15.

MRC/Wits Rural Public Health and Health Transitions Research Unit, School of Public Health, University of the Witwatersrand Faculty of Health Sciences, Johannesburg, Gauteng, South Africa

Objectives: Multimorbidity is associated with mortality in high-income countries. Our objective was to investigate the relationship between multimorbidity (≥2 of the following chronic medical conditions: hypertension, diabetes, dyslipidaemia, anaemia, HIV, angina, depression, post-traumatic stress disorder, alcohol dependence) and all-cause mortality in an older, rural black South African population. We further investigated the relationship between HIV multimorbidity (HIV as part of the multimorbidity cluster) and mortality, while testing for the effect of frailty in all models.

Design: Population cohort study.

Setting: Agincourt subdistrict of Mpumalanga province, South Africa.

Participants: 4455 individuals (54.7% female), aged ≥40 years (median age 61 years, IQR 52-71) and resident in the study area.

Primary And Secondary Outcome Measures: The primary outcome measure was time to death and the secondary outcome measure was likelihood of death within 2 years of the initial study visit. Mortality was determined during annual population surveillance updates.

Results: 3157 individuals (70.9%) had multimorbidity; 29% of these had HIV. In models adjusted for age and sociodemographic factors, multimorbidity was associated with greater risk of death (women: HR 1.72; 95% CI: 1.18 to 2.50; men: HR 1.46; 95% CI: 1.09 to 1.95) and greater odds of dying within 2 years (women: OR 2.34; 95% CI: 1.32 to 4.16; men: OR 1.51; 95% CI: 1.02 to 2.24). HIV multimorbidity was associated with increased risk of death compared with non-HIV multimorbidity in men (HR 1.93; 95% CI: 1.05 to 3.54), but was not statistically significant in women (HR 1.85; 95% CI: 0.85 to 4.04); when detectable, HIV viral loads were higher in men (p=0.021). Further adjustment for frailty slightly attenuated the associations between multimorbidity and mortality risk (women: HR 1.55; 95% CI: 1.06 to 2.26; men: HR 1.36; 95% CI: 1.01 to 1.82), but slightly increased associations between HIV multimorbidity and mortality risk.

Conclusions: Multimorbidity is associated with mortality in this older black South African population. Health systems which currently focus on HIV should be reorganised to optimise identification and management of other prevalent chronic diseases.
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http://dx.doi.org/10.1136/bmjopen-2020-047777DOI Listing
September 2021

Health Disparities And COVID-19: The Authors Reply.

Health Aff (Millwood) 2021 09;40(9):1514

California Department of Public Health Richmond, California.

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http://dx.doi.org/10.1377/hlthaff.2021.01203DOI Listing
September 2021

Effectiveness of COVID-19 Vaccines among Incarcerated People in California State Prisons: A Retrospective Cohort Study.

medRxiv 2021 Aug 18. Epub 2021 Aug 18.

Background: Prisons and jails are high-risk settings for COVID-19 transmission, morbidity, and mortality. COVID-19 vaccines may substantially reduce these risks, but evidence is needed of their effectiveness for incarcerated people, who are confined in large, risky congregate settings.

Methods: We conducted a retrospective cohort study to estimate effectiveness of mRNA vaccines, BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna), against confirmed SARS-CoV-2 infections among incarcerated people in California prisons from December 22, 2020 through March 1, 2021. The California Department of Corrections and Rehabilitation provided daily data for all prison residents including demographic, clinical, and carceral characteristics, as well as COVID-19 testing, vaccination status, and outcomes. We estimated vaccine effectiveness using multivariable Cox models with time-varying covariates that adjusted for resident characteristics and infection rates across prisons.

Findings: Among 60,707 residents in the cohort, 49% received at least one BNT162b2 or mRNA-1273 dose during the study period. Estimated vaccine effectiveness was 74% (95% confidence interval [CI], 64-82%) from day 14 after first dose until receipt of second dose and 97% (95% CI, 88-99%) from day 14 after second dose. Effectiveness was similar among the subset of residents who were medically vulnerable (74% [95% CI, 62-82%] and 92% [95% CI, 74-98%] from 14 days after first and second doses, respectively), as well as among the subset of residents who received the mRNA-1273 vaccine (71% [95% CI, 58-80%] and 96% [95% CI, 67-99%]).

Conclusions: Consistent with results from randomized trials and observational studies in other populations, mRNA vaccines were highly effective in preventing SARS-CoV-2 infections among incarcerated people. Prioritizing incarcerated people for vaccination, redoubling efforts to boost vaccination and continuing other ongoing mitigation practices are essential in preventing COVID-19 in this disproportionately affected population.

Funding: Horowitz Family Foundation, National Institute on Drug Abuse, Centers for Disease Control and Prevention, National Science Foundation, Open Society Foundation, Advanced Micro Devices.
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http://dx.doi.org/10.1101/2021.08.16.21262149DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8382129PMC
August 2021

SARS-CoV-2 testing strategies to contain school-associated transmission: model-based analysis of impact and cost of diagnostic testing, screening, and surveillance.

medRxiv 2021 Aug 10. Epub 2021 Aug 10.

Background: In March 2021, the Biden administration allocated $10 billion for COVID-19 testing in schools. We evaluate the costs and benefits of testing strategies to reduce the infection risks of full-time in-person K-8 education at different levels of community incidence.

Methods: We used an agent-based network model to simulate transmission in elementary and middle school communities, parameterized to a US school structure and assuming dominance of the delta COVID-19 variant. We assess the value of different strategies for testing students and faculty/staff, including expanded diagnostic testing ("test to stay" policies that take the place of isolation for symptomatic students or quarantine for exposed classrooms); screening (routinely testing asymptomatic individuals to identify infections and contain transmission); and surveillance (testing a random sample of students to signaling undetected transmission and trigger additional investigation or interventions).

Main Outcome Measures: We project 30-day cumulative incidence of SARS-CoV-2 infection; proportion of cases detected; proportion of planned and unplanned days out of school; and the cost of testing programs and of childcare costs associated with different strategies. For screening policies, we further estimate cost per SARS-CoV-2 infection averted in students and staff, and for surveillance, probability of correctly or falsely triggering an outbreak response at different incidence and attack rates.

Results: Accounting for programmatic and childcare costs, "test to stay" policies achieve similar model-projected transmission to quarantine policies, with reduced overall costs. Weekly universal screening prevents approximately 50% of in-school transmission, with a lower projected societal cost than hybrid or remote schooling. The cost per infection averted in students and staff by weekly screening is lower for older students and schools with higher mitigation and declines as community transmission rises. In settings where local student incidence is unknown or rapidly changing, surveillance may trigger detection of moderate-to-large in-school outbreaks with fewer resources compared to screening.

Conclusions: "Test to stay" policies and/or screening tests can facilitate consistent in-person school attendance with low transmission risk across a range of community incidence. Surveillance may be a useful reduced-cost option for detecting outbreaks and identifying school environments that may benefit from increased mitigation.
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http://dx.doi.org/10.1101/2021.05.12.21257131DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8366814PMC
August 2021

Outbreaks of COVID-19 variants in US prisons: a mathematical modelling analysis of vaccination and reopening policies.

Lancet Public Health 2021 Aug 5. Epub 2021 Aug 5.

Stanford Health Policy, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA.

Background: Residents of prisons have experienced disproportionate COVID-19-related health harms. To control outbreaks, many prisons in the USA restricted in-person activities, which are now resuming even as viral variants proliferate. This study aims to use mathematical modelling to assess the risks and harms of COVID-19 outbreaks in prisons under a range of policies, including resumption of activities.

Methods: We obtained daily resident-level data for all California state prisons from Jan 1, 2020, to May 15, 2021, describing prison layouts, housing status, sociodemographic and health characteristics, participation in activities, and COVID-19 testing, infection, and vaccination status. We developed a transmission-dynamic stochastic microsimulation parameterised by the California data and published literature. After an initial infection is introduced to a prison, the model evaluates the effect of various policy scenarios on infections and hospitalisations over 200 days. Scenarios vary by vaccine coverage, baseline immunity (0%, 25%, or 50%), resumption of activities, and use of non-pharmaceutical interventions (NPIs) that reduce transmission by 75%. We simulated five prison types that differ by residential layout and demographics, and estimated outcomes with and without repeated infection introductions over the 200 days.

Findings: If a viral variant is introduced into a prison that has resumed pre-2020 contact levels, has moderate vaccine coverage (ranging from 36% to 76% among residents, dependent on age, with 40% coverage for staff), and has no baseline immunity, 23-74% of residents are expected to be infected over 200 days. High vaccination coverage (90%) coupled with NPIs reduces cumulative infections to 2-54%. Even in prisons with low room occupancies (ie, no more than two occupants) and low levels of cumulative infections (ie, <10%), hospitalisation risks are substantial when these prisons house medically vulnerable populations. Risks of large outbreaks (>20% of residents infected) are substantially higher if infections are repeatedly introduced.

Interpretation: Balancing benefits of resuming activities against risks of outbreaks presents challenging trade-offs. After achieving high vaccine coverage, prisons with mostly one-to-two-person cells that have higher baseline immunity from previous outbreaks can resume in-person activities with low risk of a widespread new outbreak, provided they maintain widespread NPIs, continue testing, and take measures to protect the medically vulnerable.

Funding: Horowitz Family Foundation, National Institute on Drug Abuse, Centers for Disease Control and Prevention, National Science Foundation, Open Society Foundation, Advanced Micro Devices.
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http://dx.doi.org/10.1016/S2468-2667(21)00162-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8342313PMC
August 2021

Trends, mechanisms, and racial/ethnic differences of tuberculosis incidence in the US-born population aged 50 years or older in the United States.

Clin Infect Dis 2021 Jul 29. Epub 2021 Jul 29.

Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, MA, USA.

Background: Older age is a risk factor for TB in low incidence settings. Using data from the U.S. National TB Surveillance System and American Community Survey, we estimated trends and racial/ethnic differences in TB incidence among US-born cohorts aged ≥50 years.

Methods: 42,000 TB cases among US-born persons ≥50 years were reported during 2001-2019. We used generalized additive regression models to decompose the effects of birth cohort and age on TB incidence rates, stratified by sex and race/ethnicity. Using genotype-based estimates of recent transmission (available 2011-2019), we implemented additional models to decompose incidence trends by estimated recent versus remote infection.

Results: Estimated incidence rates declined with age, for the overall cohort and most sex and race/ethnicity strata. Average annual percentage declines flattened for older individuals, from 8.80% (95% confidence interval 8.34-9.23) in 51-year-olds to 4.51% (3.87-5.14) in 90-year-olds. Controlling for age, incidence rates were lower for more recent birth cohorts, dropping 8.79% (6.13-11.26) on average between successive cohort years. Incidence rates were substantially higher for racial/ethnic minorities, and these inequalities persisted across all birth cohorts. Rates from recent infection declined at approximately 10% per year as individuals aged. Rates from remote infection declined more slowly with age, and this annual percentage decline approached zero for the oldest individuals.

Conclusions: TB rates were highest for racial/ethnic minorities and for the earliest birth cohorts and declined with age. For the oldest individuals, annual percentage declines were low, and most cases were attributed to remote infection.
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http://dx.doi.org/10.1093/cid/ciab668DOI Listing
July 2021

COVID-19 in the California State Prison System: an Observational Study of Decarceration, Ongoing Risks, and Risk Factors.

J Gen Intern Med 2021 Jul 21. Epub 2021 Jul 21.

Stanford Health Policy and the Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA.

Background: Correctional institutions nationwide are seeking to mitigate COVID-19-related risks.

Objective: To quantify changes to California's prison population since the pandemic began and identify risk factors for COVID-19 infection.

Design: For California state prisons (March 1-October 10, 2020), we described residents' demographic characteristics, health status, COVID-19 risk scores, room occupancy, and labor participation. We used Cox proportional hazard models to estimate the association between rates of COVID-19 infection and room occupancy and out-of-room labor, respectively.

Participants: Residents of California state prisons.

Main Measures: Changes in the incarcerated population's size, composition, housing, and activities. For the risk factor analysis, the exposure variables were room type (cells vs. dormitories) and labor participation (any room occupant participating in the prior 2 weeks) and the outcome variable was incident COVID-19 case rates.

Key Results: The incarcerated population decreased 19.1% (119,401 to 96,623) during the study period. On October 10, 2020, 11.5% of residents were aged ≥60, 18.3% had high COVID-19 risk scores, 31.0% participated in out-of-room labor, and 14.8% lived in rooms with ≥10 occupants. Nearly 40% of residents with high COVID-19 risk scores lived in dormitories. In 9 prisons with major outbreaks (6,928 rooms; 21,750 residents), dormitory residents had higher infection rates than cell residents (adjusted hazard ratio [AHR], 2.51 95% CI, 2.25-2.80) and residents of rooms with labor participation had higher rates than residents of other rooms (AHR, 1.56; 95% CI, 1.39-1.74).

Conclusion: Despite reductions in room occupancy and mixing, California prisons still house many medically vulnerable residents in risky settings. Reducing risks further requires a combination of strategies, including rehousing, decarceration, and vaccination.
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http://dx.doi.org/10.1007/s11606-021-07022-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8294831PMC
July 2021

COVID-19 Policy Impact Evaluation: A guide to common design issues.

Am J Epidemiol 2021 Jun 28. Epub 2021 Jun 28.

Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.

Policy responses to COVID-19, particularly those related to non-pharmaceutical interventions, are unprecedented in scale and scope. However, policy impact evaluations require a complex combination of circumstance, study design, data, statistics, and analysis. Beyond the issues that are faced for any policy, evaluation of COVID-19 policies is complicated by additional challenges related to infectious disease dynamics and a multiplicity of interventions. The methods needed for policy-level impact evaluation are not often used or taught in epidemiology, and differ in important ways that may not be obvious. Methodological complications of policy evaluations can make it difficult for decision-makers and researchers to synthesize and evaluate strength of evidence in COVID-19 health policy papers. We (1) introduce the basic suite of policy impact evaluation designs for observational data, including cross-sectional analyses, pre/post, interrupted time-series, and difference-in-differences analysis, (2) demonstrate key ways in which the requirements and assumptions underlying these designs are often violated in the context of COVID-19, and (3) provide decision-makers and reviewers a conceptual and graphical guide to identifying these key violations. The overall goal of this paper is to help epidemiologists, policy-makers, journal editors, journalists, researchers, and other research consumers understand and weigh the strengths and limitations of evidence.
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http://dx.doi.org/10.1093/aje/kwab185DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8344590PMC
June 2021

Concordance between fasting plasma glucose and HbA in the diagnosis of diabetes in black South African adults: a cross-sectional study.

BMJ Open 2021 06 17;11(6):e046060. Epub 2021 Jun 17.

Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA.

Objectives: We investigated concordance between haemoglobin A1c (HbAc)-defined diabetes and fasting plasma glucose (FPG)-defined diabetes in a black South African population with a high prevalence of obesity.

Design: Cross-sectional study.

Setting: Rural South African population-based cohort.

Participants: 765 black individuals aged 40-70 years and with no history of diabetes.

Primary And Secondary Outcome Measures: The primary outcome measure was concordance between HbA-defined diabetes and FPG-defined diabetes. Secondary outcome measures were differences in anthropometric characteristics, fat distribution and insulin resistance (measured using Homoeostatic Model Assessment of Insulin Resistance (HOMA-IR)) between those with concordant and discordant HbA/FPG classifications and predictors of HbA variance.

Results: The prevalence of HbA-defined diabetes was four times the prevalence of FPG-defined diabetes (17.5% vs 4.2%). Classification was discordant in 15.7% of participants, with 111 individuals (14.5%) having HbA-only diabetes (kappa 0.23; 95% CI 0.14 to 0.31). Median body mass index, waist and hip circumference, waist-to-hip ratio, subcutaneous adipose tissue and HOMA-IR in participants with HbA-only diabetes were similar to those in participants who were normoglycaemic by both biomarkers and significantly lower than in participants with diabetes by both biomarkers (p<0.05). HOMA-IR and fat distribution explained additional HbA variance beyond glucose and age only in women.

Conclusions: Concordance was poor between HbA and FPG in diagnosis of diabetes in black South Africans, and participants with HbA-only diabetes phenotypically resembled normoglycaemic participants. Further work is necessary to determine which of these parameters better predicts diabetes-related morbidities in this population and whether a population-specific HbA threshold is necessary.
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http://dx.doi.org/10.1136/bmjopen-2020-046060DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8212405PMC
June 2021

Developing and evaluating a frailty index for older South Africans-findings from the HAALSI study.

Age Ageing 2021 Jun 9. Epub 2021 Jun 9.

AGE Research Group, NIHR Newcastle Biomedical Research Centre, Translational Clinical Research Institute, Newcastle University and Newcastle-upon-Tyne NHS Trust, Newcastle upon Tyne, UK.

Background: despite rapid population ageing, few studies have investigated frailty in older people in sub-Saharan Africa. We tested a cumulative deficit frailty index in a population of older people from rural South Africa.

Methods: analysis of cross-sectional data from the Health and Ageing in Africa: Longitudinal Studies of an INDEPTH Community (HAALSI) study. We used self-reported diagnoses, symptoms, activities of daily living, objective physiological indices and blood tests to calculate a 32-variable cumulative deficit frailty index. We fitted Cox proportional hazards models to test associations between frailty category and all-cause mortality. We tested the discriminant ability of the frailty index to predict one-year mortality alone and in addition to age and sex.

Results: in total 3,989 participants were included in the analysis, mean age 61 years (standard deviation 13); 2,175 (54.5%) were women. The median frailty index was 0.13 (interquartile range 0.09-0.19); Using population-specific cutoffs, 557 (14.0%) had moderate frailty and 263 (6.6%) had severe frailty. All-cause mortality risk was related to frailty severity independent of age and sex (hazard ratio per 0.01 increase in frailty index: 1.06 [95% confidence interval 1.04-1.07]). The frailty index alone showed moderate discrimination for one-year mortality: c-statistic 0.68-0.76; combining the frailty index with age and sex improved performance (c-statistic 0.77-0.81).

Conclusion: frailty measured by cumulative deficits is common and predicts mortality in a rural population of older South Africans. The number of measures needed may limit utility in resource-poor settings.
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http://dx.doi.org/10.1093/ageing/afab111DOI Listing
June 2021

Passing the Test: A Model-Based Analysis of Safe School-Reopening Strategies.

Ann Intern Med 2021 08 8;174(8):1090-1100. Epub 2021 Jun 8.

Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland (M.C.F.).

Background: The COVID-19 pandemic has induced historic educational disruptions. In April 2021, about 40% of U.S. public school students were not offered full-time in-person education.

Objective: To assess the risk for SARS-CoV-2 transmission in schools.

Design: An agent-based network model was developed to simulate transmission in elementary and high school communities, including home, school, and interhousehold interactions.

Setting: School structure was parametrized to reflect average U.S. classrooms, with elementary schools of 638 students and high schools of 1451 students. Daily local incidence was varied from 1 to 100 cases per 100 000 persons.

Participants: Students, faculty, staff, and adult household members.

Intervention: Isolation of symptomatic individuals, quarantine of an infected individual's contacts, reduced class sizes, alternative schedules, staff vaccination, and weekly asymptomatic screening.

Measurements: Transmission was projected among students, staff, and families after a single infection in school and over an 8-week quarter, contingent on local incidence.

Results: School transmission varies according to student age and local incidence and is substantially reduced with mitigation measures. Nevertheless, when transmission occurs, it may be difficult to detect without regular testing because of the subclinical nature of most children's infections. Teacher vaccination can reduce transmission to staff, and asymptomatic screening improves understanding of local circumstances and reduces transmission.

Limitation: Uncertainty exists about the susceptibility and infectiousness of children, and precision is low regarding the effectiveness of specific countermeasures, particularly with new variants.

Conclusion: With controlled community transmission and moderate mitigation, elementary schools can open safety, but high schools require more intensive mitigation. Asymptomatic screening can facilitate reopening at higher local incidence while minimizing transmission risk.

Primary Funding Source: Centers for Disease Control and Prevention through the Council of State and Territorial Epidemiologists, National Institute of Allergy and Infectious Diseases, National Institute on Drug Abuse, and Facebook.
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http://dx.doi.org/10.7326/M21-0600DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8252151PMC
August 2021

Cost-effectiveness of Dapagliflozin for Treatment of Patients With Heart Failure With Reduced Ejection Fraction.

JAMA Cardiol 2021 Aug;6(8):926-935

Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, California.

Importance: In the Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure (DAPA-HF) trial, dapagliflozin was shown to reduce cardiovascular mortality and hospitalizations due to heart failure while improving patient-reported health status. However, the cost-effectiveness of adding dapagliflozin therapy to standard of care (SOC) is unknown.

Objective: To estimate the cost-effectiveness of dapagliflozin therapy among patients with chronic heart failure with reduced ejection fraction (HFrEF).

Design, Setting, And Participants: This Markov cohort cost-effectiveness model used estimates of therapy effectiveness, transition probabilities, and utilities from the DAPA-HF trial and other published literature. Costs were derived from published sources. Patients with HFrEF included subgroups based on diabetes status and health status impairment due to heart failure. We compiled parameters from the literature including DAPA-HF, on which our model is based, and many other sources from December 2019 to February 27, 2021. We performed our analysis in February 2021.

Exposures: Dapagliflozin or SOC.

Main Outcomes And Measures: Hospitalizations for heart failure, life-years, quality-adjusted life-years (QALYs), costs, and the cost per QALY gained (incremental cost-effectiveness ratio).

Results: In the model, dapagliflozin therapy yielded a mean of 0.78 additional life-years and 0.46 additional QALYs compared with SOC at an incremental cost of $38 212, resulting in a cost per QALY gained of $83 650. The cost per QALY was similar for patients with or without diabetes and for patients with mild or moderate impairment of health status due to heart failure. The cost-effectiveness was most sensitive to estimates of the effect on mortality and duration of therapy effectiveness. If the cost of dapagliflozin decreased from $474 to $270 (43% decline), the cost per QALY gained would drop below $50 000.

Conclusions And Relevance: These findings suggest that dapagliflozin provides intermediate value compared with SOC, based on American College of Cardiology/American Heart Association benchmarks. Additional data regarding the magnitude of mortality reduction would improve the precision of cost-effectiveness estimates.
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http://dx.doi.org/10.1001/jamacardio.2021.1437DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8156166PMC
August 2021

Impact of treatment duration on mortality among Veterans with opioid use disorder in the United States Veterans Health Administration.

Addiction 2021 May 17. Epub 2021 May 17.

Center for Health Policy and Center for Primary Care and Outcomes Research, Stanford University School of Medicine, Stanford, CA, USA.

Background And Aims: While long-term medication-assisted treatment (MAT) using methadone or buprenorphine is associated with significantly lower all-cause mortality for individuals with opioid use disorder (OUD), periods of initiating or discontinuing treatment are associated with higher mortality risks relative to stable treatment. This study aimed to identify the OUD treatment durations necessary for the elevated mortality risks during treatment transitions to be balanced by reductions in mortality while receiving treatment.

Design: Simulation model based on a compartmental model of OUD diagnosis, MAT receipt and all-cause mortality among Veterans with OUD in the United States Veterans Health Administration (VA) in 2017-2018. We simulated methadone and buprenorphine treatments of varying durations using parameters obtained through calibration and published meta-analyses of studies from North America, Europe and Australia.

Setting: United States.

Participants: Simulated cohorts of 10 000 individuals with OUD.

Measurements: All-cause mortality over 12 months.

Findings: Receiving methadone for 4 months or longer or buprenorphine for 2 months or longer resulted in 54 [95% confidence interval (CI) = 5-90] and 65 (95% CI = 21-89) fewer deaths relative to not receiving MAT for the same duration, using VA-specific mortality rates. We estimated shorter treatment durations necessary to achieve net mortality benefits of 2 months or longer for methadone and 1 month or longer for buprenorphine, using non-VA population literature estimates. Sensitivity analyses demonstrated that necessary treatment durations increased more with smaller mortality reductions on treatment than with larger relative risks during treatment transitions.

Conclusions: Short periods (< 6 months) of treatment with either methadone or buprenorphine are likely to yield net mortality benefits for people with opioid use disorder relative to receiving no medications, despite periods of elevated all-cause mortality risk during transitions into and out of treatment. Retaining people with opioid use disorder in treatment longer can increase these benefits.
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http://dx.doi.org/10.1111/add.15574DOI Listing
May 2021

Modeling the Cost-Effectiveness of Express Multi-Site Gonorrhea Screening among Men Who Have Sex with Men in the United States.

Sex Transm Dis 2021 Jul 5. Epub 2021 Jul 5.

Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut (Rebecca Earnest); Prevention Policy Modeling Lab, Department of Global Health and Population, Harvard T. H. Chan School of Public Health, Boston, Massachusetts (Rebecca Earnest, Minttu M Rönn, Meghan Bellerose, Christian Testa, Yelena Malyuta, Nicolas A Menzies, Joshua A Salomon); Guy's and St Thomas' Hospitals NHS Foundation Trust, London, UK (AS Menon-Johansson); Division of STD Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia (Thomas L Gift, Andrés A Berruti, Harrell W Chesson); Division of STD Prevention and HIV/AIDS Surveillance, Massachusetts Department of Public Health, Boston, Massachusetts (Katherine K Hsu); and Center for Health Policy/Center for Primary Care and Outcomes Research, School of Medicine, Stanford University, Stanford, California (Lin Zhu, Joshua A Salomon).

Background: Men who have sex with men (MSM) experience high rates of gonococcal infection at extragenital (rectal and pharyngeal) anatomic sites, which often are missed without asymptomatic screening and may be important for onward transmission. Implementing an express pathway for asymptomatic MSM seeking routine screening at their clinic may be a cost-effective way to improve extragenital screening by allowing patients to be screened at more anatomic sites through a streamlined, less costly process.

Methods: We modified an agent-based model of anatomic site-specific gonococcal infection in U.S. MSM to assess the cost-effectiveness of an express screening pathway in which all asymptomatic MSM presenting at their clinic were screened at the urogenital, rectal, and pharyngeal sites but forewent a provider consultation and physical exam and self-collected their own samples. We calculated the cumulative health effects expressed as gonococcal infections and cases averted over five years, labor and material costs, and incremental cost effectiveness ratios (ICER) for express versus traditional scenarios.

Results: The express scenario averted more infections and cases in each intervention year. The increased diagnostic costs of triple-site screening were largely offset by the lowered visit costs of the express pathway and, from the end of year 3 onward, this pathway generated small cost savings. However, in a sensitivity analysis of assumed overhead costs, cost savings under the express scenario disappeared in the majority of simulations once overhead costs exceeded 7% of total annual costs.

Conclusions: Express screening may be a cost-effective option for improving multi-site anatomic screening among U.S. MSM.
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http://dx.doi.org/10.1097/OLQ.0000000000001467DOI Listing
July 2021

Racial/Ethnic Disparities In COVID-19 Exposure Risk, Testing, And Cases At The Subcounty Level In California.

Health Aff (Millwood) 2021 06 12;40(6):870-878. Epub 2021 May 12.

Jeremy D. Goldhaber-Fiebert is an associate professor in the Centers for Health Policy and Primary Care and Outcomes Research, Stanford Health Policy, Freeman Spogli Institute for International Studies and the Stanford School of Medicine, Stanford University.

With a population of forty million and substantial geographic variation in sociodemographics and health services, California is an important setting in which to study disparities. Its population (37.5 percent White, 39.1 percent Latino, 5.3 percent Black, and 14.4 percent Asian) experienced 59,258 COVID-19 deaths through April 14, 2021-the most of any state. We analyzed California's racial/ethnic disparities in COVID-19 exposure risks, testing rates, test positivity, and case rates through October 2020, combining data from 15.4 million SARS-CoV-2 tests with subcounty exposure risk estimates from the American Community Survey. We defined "high-exposure-risk" households as those with one or more essential workers and fewer rooms than inhabitants. Latino people in California are 8.1 times more likely to live in high-exposure-risk households than White people (23.6 percent versus 2.9 percent), are overrepresented in cumulative cases (3,784 versus 1,112 per 100,000 people), and are underrepresented in cumulative testing (35,635 versus 48,930 per 100,000 people). These risks and outcomes were worse for Latino people than for members of other racial/ethnic minority groups. Subcounty disparity analyses can inform targeting of interventions and resources, including community-based testing and vaccine access measures. Tracking COVID-19 disparities and developing equity-focused public health programming that mitigates the effects of systemic racism can help improve health outcomes among California's populations of color.
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http://dx.doi.org/10.1377/hlthaff.2021.00098DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8458028PMC
June 2021

Cost-Effectiveness of One-Time Universal Screening for Chronic Hepatitis B Infection in Adults in the United States.

Clin Infect Dis 2021 May 6. Epub 2021 May 6.

Asian Liver Center, Department of Surgery, Stanford University School of Medicine, Palo Alto, California, USA.

Background: An estimated 862,000 to 2.4 million people have chronic hepatitis B infection (CHB). Left undiagnosed and untreated CHB increases risk of death from liver cirrhosis or liver cancer. Hepatitis B screening is recommended for pregnant women and populations with increased CHB risk, but diagnosis rates remain low with only 33% of people with CHB aware of their infection.. This study aimed to assess the cost-effectiveness of universal adult screening for CHB.

Methods: We used a Markov model to calculate the costs, population health impact and cost-effectiveness of one-time universal screening and CHB monitoring and treatment compared to current practice. Sensitivity analysis was performed on model parameters to identify thresholds for cost-savings or cost-effectiveness based on willinness-to-pay of $50,000/QALY . The analysis assumed testing would be performed during routine healthcare visits, and generic tenofovir or entecavir would be dispensed for treatment. Testing costs were based on Medicare reimbursement rates.

Results: At an estimated 0.24% prevalence of undiagnosed CHB, universal HBsAg screening in adults 18-69 years old is cost-saving compared with current practice if antiviral treatment drug costs remain below $894 per year. Compared with current practice, universal screening would avert an additional 7.4 cases of compensated cirrhosis, 3.3 cases of decompensated cirrhosis, 5.5 cases of hepatocellular carcinoma, 1.9 liver transplants, and 10.3 HBV related deaths at a savings of $263,000 per 100,000 adults screened.

Conclusion: Universal HBsAg screening of adults in the US general population for CHB is cost-effective and likely cost-saving compared to current CHB screening recommendations.
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http://dx.doi.org/10.1093/cid/ciab405DOI Listing
May 2021

How do Japanese rate the severity of different diseases and injuries?-an assessment of disability weights for 231 health states by 37,318 Japanese respondents.

Popul Health Metr 2021 04 23;19(1):21. Epub 2021 Apr 23.

Institute for Population Health, King's College London, London, UK.

Background: Disability weights (DWs) are weight factors that reflect the severity of health states for estimates of disability-adjusted life years. A new set of global DWs was published for the Global Burden of Diseases and Injuries (GBD) 2013 study, which relied on sampling from various world regions, but included little data for countries in East Asia. This study aimed to measure DWs in Japan using comparable methods, and compare the results with previous estimates from the GBD 2013 DW study.

Methods: We conducted a web-based survey in 2019 to estimate DWs for 231 health states for the Japanese population. The survey included five new health states but otherwise followed the method of the GBD DW measurement study. The survey consisted of 15 paired comparison (PC) questions and 3 population health equivalence questions (PHE) per respondent. We analyzed PC data using probit regression and rescaled results to DW units between 0 (equivalent to full health) and 1 (equivalent to death).

Findings: We considered 37,318 nationally representative respondents. The values of the resulting DWs ranged from 0.707 (95% uncertainty interval (UI) 0.527-0.842) for spinal cord injury at neck level (untreated) to 0.004 (UI 0.001-0.009) for mild anemia. High correlation between Japanese DW and GBD 2013 DW was observed, but there was considerable disagreement. Out of 226 comparable health states, 55 (24.3%) showed more than a factor-of-two difference, of which 41 (74.6%) had a higher value in Japanese DW. Many of the health states with higher DW in the Japan study were injuries, including amputation and fracture, and hearing and vision loss, while mental, behavioral, and substance use disorders generally tended to be lower.

Conclusions: This study has created an empirical basis for assessment of Japanese DWs of health status. The findings from this study based on the Japanese population suggest that there might be contextual differences in rating the severity of health states compared to previous surveys conducted elsewhere.
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http://dx.doi.org/10.1186/s12963-021-00253-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8063365PMC
April 2021

Reconstructing the course of the COVID-19 epidemic over 2020 for US states and counties: results of a Bayesian evidence synthesis model.

medRxiv 2021 Jul 22. Epub 2021 Jul 22.

Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts US.

Reported COVID-19 cases and deaths provide a delayed and incomplete picture of SARS-CoV-2 infections in the United States (US). Accurate estimates of both the timing and magnitude of infections are needed to characterize viral transmission dynamics and better understand COVID-19 disease burden. We estimated time trends in SARS-CoV-2 transmission and other COVID-19 outcomes for every county in the US, from the first reported COVID-19 case in January 13, 2020 through January 1, 2021. To do so we employed a Bayesian modeling approach that explicitly accounts for reporting delays and variation in case ascertainment, and generates daily estimates of incident SARS-CoV-2 infections on the basis of reported COVID-19 cases and deaths. The model is freely available as the R package. Nationally, we estimated there had been 49 million symptomatic COVID-19 cases and 400,718 COVID-19 deaths by the end of 2020, and that 27% of the US population had been infected. The results also demonstrate wide county-level variability in the timing and magnitude of incidence, with local epidemiological trends differing substantially from state or regional averages, leading to large differences in the estimated proportion of the population infected by the end of 2020. Our estimates of true COVID-19 related deaths are consistent with independent estimates of excess mortality, and our estimated trends in cumulative incidence of SARS-CoV-2 infection are consistent with trends in seroprevalence estimates from available antibody testing studies. Reconstructing the underlying incidence of SARS-CoV-2 infections across US counties allows for a more granular understanding of disease trends and the potential impact of epidemiological drivers.
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http://dx.doi.org/10.1101/2020.06.17.20133983DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8043480PMC
July 2021

Better Late Than Never: Trends in COVID-19 Infection Rates, Risk Perceptions, and Behavioral Responses in the USA.

J Gen Intern Med 2021 06 29;36(6):1825-1828. Epub 2021 Mar 29.

Perelman School of Medicine, Department of Medical Ethics and Health Policy, University of Pennsylvania, Philadelphia, PA, USA.

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http://dx.doi.org/10.1007/s11606-021-06633-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8006886PMC
June 2021

Covid-19 in the California State Prison System: An Observational Study of Decarceration, Ongoing Risks, and Risk Factors.

medRxiv 2021 Mar 8. Epub 2021 Mar 8.

Stanford Health Policy and the Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA.

Background: Correctional institutions nationwide are seeking to mitigate Covid-19-related risks.

Objective: To quantify changes to California's prison population since the pandemic began and identify risk factors for Covid-19 infection.

Design: We described residents' demographic characteristics, health status, Covid-19 risk scores, room occupancy, and labor participation. We used Cox proportional hazard models to estimate the association between rates of Covid-19 infection and room occupancy and out-of-room labor, respectively.

Setting: California state prisons (March 1-October 10, 2020).

Participants: Residents of California state prisons.

Measurements: Changes in the incarcerated population's size, composition, housing, and activities. For the risk factor analysis, the exposure variables were room type (cells vs dormitories) and labor participation (any room occupant participating in the prior 2 weeks) and the outcome variable was incident Covid-19 case rates.

Results: The incarcerated population decreased 19.1% (119,401 to 96,623) during the study period.On October 10, 2020, 11.5% of residents were aged ≥60, 18.3% had high Covid-19 risk scores, 31.0% participated in out-of-room labor, and 14.8% lived in rooms with ≥10 occupants. Nearly 40% of residents with high Covid-19 risk scores lived in dormitories. In 9 prisons with major outbreaks (6,928 rooms; 21,750 residents), dormitory residents had higher infection rates than cell residents (adjusted hazard ratio [AHR], 2.51 95%CI, 2.25-2.80) and residents of rooms with labor participation had higher rates than residents of other rooms (AHR, 1.56; 95%CI, 1.39-1.74).

Limitations: Inability to measure density of residents' living conditions or contact networks among residents and staff.

Conclusion: Despite reductions in room occupancy and mixing, California prisons still house many medically vulnerable residents in risky settings. Reducing risks further requires a combination of strategies, including rehousing, decarceration, and vaccination.

Funding Sources: Horowitz Family Foundation; National Institute on Drug Abuse; National Science Foundation Graduate Research Fellowship; Open Society Foundations.
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http://dx.doi.org/10.1101/2021.03.04.21252942DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7987024PMC
March 2021

Mapping Inequality in SARS-CoV-2 Household Exposure and Transmission Risk in the USA.

J Gen Intern Med 2021 05 18;36(5):1476-1478. Epub 2021 Feb 18.

Stanford Health Policy, Centers for Health Policy and Primary Care and Outcomes Research, Department of Medicine, Stanford University, 615 Crothers Way, Stanford, CA, 94305, USA.

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http://dx.doi.org/10.1007/s11606-021-06603-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7891469PMC
May 2021

Nationwide cost-effectiveness analysis of surgical stabilization of rib fractures by flail chest status and age groups.

J Trauma Acute Care Surg 2021 03;90(3):451-458

From the Department of Surgery (J.C., L.T., D.A.S., J.D.F.), Division of General Surgery, Department of Epidemiology and Population Health (J.C.), Surgeons Writing About Trauma (J.C., B.M., R.T., L.T., D.A.S., J.D.F.), and School of Medicine (B.M., R.T.), Stanford University, Stanford, California; Department of Surgery, Chulalongkorn University (W.L.), Bangkok, Thailand; and Stanford Health Policy (J.A.S., J.D.G.-F.), Centers for Health Policy and Primary Care and Outcomes Research, Stanford University, Stanford, California.

Background: Surgical stabilization of rib fracture (SSRF) is increasingly used to manage patients with rib fractures. Benefits of performing SSRF appear variable, and the procedure is costly, necessitating cost-effectiveness analysis for distinct subgroups. We aimed to assess the cost-effectiveness of SSRF versus nonoperative management among patients with rib fractures younger than 65 years versus 65 years or older, with versus without flail chest. We hypothesized that, compared with nonoperative management, SSRF is cost-effective only for patients with flail chest.

Methods: This economic evaluation used a decision-analytic Markov model with a lifetime time horizon incorporating US population-representative inputs to simulate benefits and risks of SSRF compared with nonoperative management. We report quality-adjusted life years (QALYs), costs, and incremental cost-effectiveness ratios. Deterministic and probabilistic sensitivity analyses accounted for most plausible clinical scenarios.

Results: Compared with nonoperative management, SSRF was cost-effective for patients with flail chest at willingness-to-pay threshold of US $150,000/QALY gained. Surgical stabilization of rib fracture costs US $25,338 and US $123,377/QALY gained for those with flail chest younger than 65 years and 65 years or older, respectively. Surgical stabilization of rib fracture was not cost-effective for patients without flail chest, costing US $172,704 and US $243,758/QALY gained for those younger than 65 years and 65 years or older, respectively. One-way sensitivity analyses showed that, under most plausible scenarios, SSRF remained cost-effective for subgroups with flail chest, and nonoperative management remained cost-effective for patients older than 65 years without flail chest. Probability that SSRF is cost-effective ranged from 98% among patients younger than 65 years with flail chest to 35% among patients 65 years or older without flail chest.

Conclusions: Surgical stabilization of rib fracture is cost-effective for patients with flail chest. Surgical stabilization of rib fracture may be cost-effective in some patients without flail chest, but delineating these patients requires further study.

Level Of Evidence: Economic/decision, level II.
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http://dx.doi.org/10.1097/TA.0000000000003021DOI Listing
March 2021

The Use and Misuse of Mathematical Modeling for Infectious Disease Policymaking: Lessons for the COVID-19 Pandemic.

Med Decis Making 2021 05 3;41(4):379-385. Epub 2021 Feb 3.

Department of Global Health and Population, Harvard T. H. Chan School of Public Health, Boston, MA, USA.

Mathematical modeling has played a prominent and necessary role in the current coronavirus disease 2019 (COVID-19) pandemic, with an increasing number of models being developed to track and project the spread of the disease, as well as major decisions being made based on the results of these studies. A proliferation of models, often diverging widely in their projections, has been accompanied by criticism of the validity of modeled analyses and uncertainty as to when and to what extent results can be trusted. Drawing on examples from COVID-19 and other infectious diseases of global importance, we review key limitations of mathematical modeling as a tool for interpreting empirical data and informing individual and public decision making. We present several approaches that have been used to strengthen the validity of inferences drawn from these analyses, approaches that will enable better decision making in the current COVID-19 crisis and beyond.
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http://dx.doi.org/10.1177/0272989X21990391DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7862917PMC
May 2021

Passing the Test: A model-based analysis of safe school-reopening strategies.

medRxiv 2021 Jan 29. Epub 2021 Jan 29.

Center for Vaccine Development and Global Health, University of Maryland School of Medicine.

Background: The COVID-19 pandemic has induced historic educational disruptions. In December 2020, at least two-thirds of US public school students were not attending full-time in-person education. The Biden Administration has expressed that reopening schools is a priority.

Objective: To compare risks of SARS-COV-2 transmission in schools across different school-based prevention strategies and levels of community transmission.

Design: We developed an agent-based network model to simulate transmission in elementary and high school communities, including home, school, and inter-household interactions.

Setting: We parameterized school structure based on average US classrooms, with elementary schools of 638 students and high schools of 1,451 students. We varied daily community incidence from 1 to 100 cases per 100,000 population. Patients (or Participants). We simulated students, faculty/staff, and adult household members.

Interventions: We evaluated isolation of symptomatic individuals, quarantine of an infected individual's contacts, reduced class sizes, alternative schedules, staff vaccination, and weekly asymptomatic screening.

Measurements: We projected transmission among students, staff and families during one month following introduction of a single infection into a school. We also calculated the number of infections expected for a typical 8-week quarter, contingent on community incidence rate.

Results: School transmission risk varies according to student age and community incidence and is substantially reduced with effective, consistent mitigation measures. Nevertheless, when transmission occurs, it may be difficult to detect without regular, frequent testing due to the subclinical nature of most infections in children. Teacher vaccination can reduce transmission to staff, while asymptomatic screening both improves understanding of local circumstances and reduces transmission, facilitating five-day schedules at full classroom capacity.

Limitations: There is uncertainty about susceptibility and infectiousness of children and low precision regarding the effectiveness of specific prevention measures, particularly with emergence of new variants.

Conclusion: With controlled community transmission and moderate school-based prevention measures, elementary schools can open with few in-school transmissions, while high schools require more intensive mitigation. Asymptomatic screening can both reduce transmission and provide useful information for decision-makers.
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http://dx.doi.org/10.1101/2021.01.27.21250388DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7852255PMC
January 2021

Adaptive Policies to Balance Health Benefits and Economic Costs of Physical Distancing Interventions during the COVID-19 Pandemic.

Med Decis Making 2021 05 27;41(4):386-392. Epub 2021 Jan 27.

Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA.

Policy makers need decision tools to determine when to use physical distancing interventions to maximize the control of COVID-19 while minimizing the economic and social costs of these interventions. We describe a pragmatic decision tool to characterize adaptive policies that combine real-time surveillance data with clear decision rules to guide when to trigger, continue, or stop physical distancing interventions during the current pandemic. In model-based experiments, we find that adaptive policies characterized by our proposed approach prevent more deaths and require a shorter overall duration of physical distancing than alternative physical distancing policies. Our proposed approach can readily be extended to more complex models and interventions.
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http://dx.doi.org/10.1177/0272989X21990371DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8084913PMC
May 2021

How do Covid-19 policy options depend on end-of-year holiday contacts in Mexico City Metropolitan Area? A Modeling Study.

medRxiv 2020 Dec 22. Epub 2020 Dec 22.

Background: With more than 20 million residents, Mexico City Metropolitan Area (MCMA) has the largest number of Covid-19 cases in Mexico and is at risk of exceeding its hospital capacity in late December 2020.

Methods: We used SC-COSMO, a dynamic compartmental Covid-19 model, to evaluate scenarios considering combinations of increased contacts during the holiday season, intensification of social distancing, and school reopening. Model parameters were derived from primary data from MCMA, published literature, and calibrated to time-series of incident confirmed cases, deaths, and hospital occupancy. Outcomes included projected confirmed cases and deaths, hospital demand, and magnitude of hospital capacity exceedance.

Findings: Following high levels of holiday contacts even with no in-person schooling, we predict that MCMA will have 1·0 million (95% prediction interval 0·5 - 1·7) additional Covid-19 cases between December 7, 2020 and March 7, 2021 and that hospitalizations will peak at 35,000 (14,700 - 67,500) on January 27, 2021, with a >99% chance of exceeding Covid-19-specific capacity (9,667 beds). If holiday contacts can be controlled, MCMA can reopen in-person schools provided social distancing is increased with 0·5 million (0·2 - 1·0) additional cases and hospitalizations peaking at 14,900 (5,600 - 32,000) on January 23, 2021 (77% chance of exceedance).

Interpretation: MCMA must substantially increase Covid-19 hospital capacity under all scenarios considered. MCMA's ability to reopen schools in mid-January 2021 depends on sustaining social distancing and that contacts during the end-of-year holiday were well controlled.

Funding: Society for Medical Decision Making, Gordon and Betty Moore Foundation, and Wadhwani Institute for Artificial Intelligence Foundation.

Research In Context: As of mid-December 2020, Mexico has the twelfth highest incidence of confirmed cases of Covid-19 worldwide and its epidemic is currently growing. Mexico's case fatality ratio (CFR) - 9·1% - is the second highest in the world. With more than 20 million residents, Mexico City Metropolitan Area (MCMA) has the highest number and incidence rate of Covid-19 confirmed cases in Mexico and a CFR of 8·1%. MCMA is nearing its current hospital capacity even as it faces the prospect of increased social contacts during the 2020 end-of-year holidays. There is limited Mexico-specific evidence available on epidemic, such as parameters governing time-dependent mortality, hospitalization and transmission. Literature searches required supplementation through primary data analysis and model calibration to support the first realistic model-based Covid-19 policy evaluation for Mexico, which makes this analysis relevant and timely. Study strengths include the use of detailed primary data provided by MCMA; the Bayesian model calibration to enable evaluation of projections and their uncertainty; and consideration of both epidemic and health system outcomes. The model projects that failure to limit social contacts during the end-of-year holidays will substantially accelerate MCMA's epidemic (1·0 million (95% prediction interval 0·5 - 1·7) additional cases by early March 2021). Hospitalization demand could reach 35,000 (14,700 - 67,500), with a >99% chance of exceeding current capacity (9,667 beds). Controlling social contacts during the holidays could enable MCMA to reopen in-person schooling without greatly exacerbating the epidemic provided social distancing in both schools and the community were maintained. Under all scenarios and policies, current hospital capacity appears insufficient, highlighting the need for rapid capacity expansion. MCMA officials should prioritize rapid hospital capacity expansion. MCMA's ability to reopen schools in mid-January 2021 depends on sustaining social distancing and that contacts during the end-of-year holiday were well controlled.
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http://dx.doi.org/10.1101/2020.12.21.20248597DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7781344PMC
December 2020

Alternative Dose Allocation Strategies to Increase Benefits From Constrained COVID-19 Vaccine Supply.

Ann Intern Med 2021 04 5;174(4):570-572. Epub 2021 Jan 5.

Center for Health Policy, School of Medicine, Stanford University, Stanford, California.

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http://dx.doi.org/10.7326/M20-8137DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7808325PMC
April 2021

High-resolution estimates of tuberculosis incidence among non-U.S.-born persons residing in the United States, 2000-2016.

Epidemics 2020 12 10;33:100419. Epub 2020 Nov 10.

Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, MA, USA.

In the United States, new tuberculosis cases are increasingly concentrated within non-native-born populations. We estimated trends and differences in tuberculosis incidence rates for the non-U.S.-born population, at a resolution unobtainable from raw data. We obtained non-U.S.-born tuberculosis case reports for 2000-2016 from the National Tuberculosis Surveillance System, and population data from the American Community Survey and 2000 U.S. Census. We constructed generalized additive regression models to estimate incidence rates in terms of birth country, entry year, age at entry, and number of years since entry into the United States and described how these factors contribute to overall tuberculosis risk. Controlling for other factors, tuberculosis incidence rates were lower for more recent immigration cohorts, with an incidence risk ratio (IRR) of 10.2 (95 % confidence interval 7.0, 14.7) for the 1950 entry cohort compared to its 2016 counterpart. Greater years since entry and younger age at entry were associated with substantially lower incidence rates. IRRs for birth country varied between 8.86 (6.78, 11.52) for Somalia and 0.02 (0.01, 0.03) for Canada, compared to all non-U.S.-born residents in 2016. IRRs were positively correlated with WHO predicted incidence rate and negatively associated with wealth level for the birth country. Lower country wealth level was also associated with shallower declines in tuberculosis over time. Tuberculosis risks differ by several orders of magnitude within the non-U.S.-born population. A better understanding of these differences will allow more effective targeting of tuberculosis prevention efforts. The methods presented here may also be relevant for understanding tuberculosis trends in other high-income countries.
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http://dx.doi.org/10.1016/j.epidem.2020.100419DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7808561PMC
December 2020
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