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1.
BMJ Med ; 2(1): e000399, 2023.
Article in English | MEDLINE | ID: covidwho-2325941

ABSTRACT

Medical and population health science researchers frequently make ambiguous statements about whether they believe their study sample or results are representative of some (implicit or explicit) target population. This article provides a comprehensive definition of representativeness, with the goal of capturing the different ways in which a study can be representative of a target population. It is proposed that a study is representative if the estimate obtained in the study sample is generalisable to the target population (owing to representative sampling, estimation of stratum specific effects, or quantitative methods to generalise or transport estimates) or the interpretation of the results is generalisable to the target population (based on fundamental scientific premises and substantive background knowledge). This definition is explored in the context of four covid-19 studies, ranging from laboratory science to descriptive epidemiology. All statements regarding representativeness should make clear the way in which the study results generalise, the target population the results are being generalised to, and the assumptions that must hold for that generalisation to be scientifically or statistically justifiable.

2.
Clin Infect Dis ; 2022 May 17.
Article in English | MEDLINE | ID: covidwho-2235596

ABSTRACT

BACKGROUND: The efficacy of SARS-CoV-2 convalescent plasma (CCP) for preventing infection in exposed, uninfected individuals is unknown. CCP might prevent infection when administered before symptoms or laboratory evidence of infection. METHODS: This double-blinded, phase 2 randomized, controlled trial (RCT) compared the efficacy and safety of prophylactic high titer (≥1:320 by Euroimmun ELISA) CCP with standard plasma. Asymptomatic participants aged ≥18 years with close contact exposure to a person with confirmed COVID-19 in the previous 120 hours and negative SARS-CoV-2 test within 24 hours before transfusion were eligible. The primary outcome was new SARS-CoV-2 infection. RESULTS: 180 participants were enrolled; 87 were assigned to CCP and 93 to control plasma, and 170 transfused at 19 sites across the United States from June 2020 to March 2021. Two were excluded for screening SARS-CoV-2 RT-PCR positivity. Of the remaining 168 participants, 12/81 (14·8%) CCP and 13/87 (14·9%) control recipients developed SARS-CoV-2 infection; 6 (7·4%) CCP and 7 (8%) control recipients developed COVID-19 (infection with symptoms). There were no COVID-19-related hospitalizations in CCP and 2 in control recipients. Efficacy by restricted mean infection free time (RMIFT) by 28 days for all SARS-CoV-2 infections (25·3 vs. 25·2 days; p = 0·49) and COVID-19 (26·3 vs. 25·9 days; p = 0·35) was similar for both groups. CONCLUSIONS: Administration of high-titer CCP as post-exposure prophylaxis, while appearing safe, did not prevent SARS-CoV-2 infection.

3.
Transfusion ; 2022 Nov 07.
Article in English | MEDLINE | ID: covidwho-2232067

ABSTRACT

BACKGROUND: While the use of convalescent plasma (CP) in the ongoing COVID-19 pandemic has been inconsistent, CP has the potential to reduce excess morbidity and mortality in future pandemics. Given constraints on CP supply, decisions surrounding the allocation of CP must be made. STUDY DESIGN AND METHODS: Using a discrete-time stochastic compartmental model, we simulated implementation of four potential allocation strategies: administering CP to individuals in early hospitalization with COVID-19; administering CP to individuals in outpatient settings; administering CP to hospitalized individuals and administering any remaining CP to outpatient individuals and administering CP in both settings while prioritizing outpatient individuals. We examined the final size of SARS-CoV-2 infections, peak and cumulative hospitalizations, and cumulative deaths under each of the allocation scenarios over a 180-day period. We compared the cost per weighted health benefit under each strategy. RESULTS: Prioritizing administration to patients in early hospitalization, with remaining plasma administered in outpatient settings, resulted in the highest reduction in mortality, averting on average 15% more COVID-19 deaths than administering to hospitalized individuals alone (95% CI [11%-18%]). Prioritizing administration to outpatients, with remaining plasma administered to hospitalized individuals, had the highest percentage of hospitalizations averted (22% [21%-23%] higher than administering to hospitalized individuals alone). DISCUSSION: Convalescent plasma allocation strategy should be determined by the relative priority of averting deaths, infections, or hospitalizations. Under conditions considered, mixed allocation strategies (allocating CP to both outpatient and hospitalized individuals) resulted in a larger percentage of infections and deaths averted than administering CP in a single setting.

4.
Drug Alcohol Depend ; : 109382, 2022 Mar 03.
Article in English | MEDLINE | ID: covidwho-1828363

ABSTRACT

BACKGROUND: Alcohol use during the COVID-19 pandemic increased. People living with HIV or at risk for HIV acquisition often have psycho-social and structural barriers or co-occurring substance use making them vulnerable to the adverse effects of alcohol. We describe factors associated with alcohol use during the COVID-19 pandemic in this group. METHODS: From May 2020 to February 2021, 1984 people enrolled in 6 existing cohort studies completed surveys about alcohol and other drug use during the COVID-19 pandemic. We describe the past-month prevalence of no alcohol use, low-risk use, and hazardous use. We use multinomial regression to describe factors associated with low-risk or hazardous alcohol use relative to no alcohol use. RESULTS: Forty-five percent of participants reported no alcohol use, 33% low-risk use, and 22% hazardous use in the past 30 days. Cannabis and stimulant use were associated with a higher prevalence of low-risk use relative to no use. Tobacco, stimulant, cannabis use and recent overdose were associated with a higher prevalence of hazardous use relative to no use. Substance use treatment and living with HIV were associated with a lower prevalence of low-risk or hazardous use relative to no use. CONCLUSIONS: Stimulant use was strongly associated with a higher prevalence of hazardous alcohol use while engagement in substance use treatment or living with HIV was associated with a lower prevalence. Ascertaining hazardous alcohol and other drug use, particularly stimulants, in clinical care could identify people at higher risk for adverse outcome and harm reduction counseling.

5.
N Engl J Med ; 386(18): 1700-1711, 2022 05 05.
Article in English | MEDLINE | ID: covidwho-1768967

ABSTRACT

BACKGROUND: Polyclonal convalescent plasma may be obtained from donors who have recovered from coronavirus disease 2019 (Covid-19). The efficacy of this plasma in preventing serious complications in outpatients with recent-onset Covid-19 is uncertain. METHODS: In this multicenter, double-blind, randomized, controlled trial, we evaluated the efficacy and safety of Covid-19 convalescent plasma, as compared with control plasma, in symptomatic adults (≥18 years of age) who had tested positive for severe acute respiratory syndrome coronavirus 2, regardless of their risk factors for disease progression or vaccination status. Participants were enrolled within 8 days after symptom onset and received a transfusion within 1 day after randomization. The primary outcome was Covid-19-related hospitalization within 28 days after transfusion. RESULTS: Participants were enrolled from June 3, 2020, through October 1, 2021. A total of 1225 participants underwent randomization, and 1181 received a transfusion. In the prespecified modified intention-to-treat analysis that included only participants who received a transfusion, the primary outcome occurred in 17 of 592 participants (2.9%) who received convalescent plasma and 37 of 589 participants (6.3%) who received control plasma (absolute risk reduction, 3.4 percentage points; 95% confidence interval, 1.0 to 5.8; P = 0.005), which corresponded to a relative risk reduction of 54%. Evidence of efficacy in vaccinated participants cannot be inferred from these data because 53 of the 54 participants with Covid-19 who were hospitalized were unvaccinated and 1 participant was partially vaccinated. A total of 16 grade 3 or 4 adverse events (7 in the convalescent-plasma group and 9 in the control-plasma group) occurred in participants who were not hospitalized. CONCLUSIONS: In participants with Covid-19, most of whom were unvaccinated, the administration of convalescent plasma within 9 days after the onset of symptoms reduced the risk of disease progression leading to hospitalization. (Funded by the Department of Defense and others; CSSC-004 ClinicalTrials.gov number, NCT04373460.).


Subject(s)
COVID-19 , Immunization, Passive , Adult , Ambulatory Care , COVID-19/therapy , Disease Progression , Double-Blind Method , Hospitalization , Humans , Immunization, Passive/adverse effects , Immunization, Passive/methods , Treatment Outcome , United States , COVID-19 Serotherapy
6.
Drug Alcohol Depend ; : 109355, 2022 Feb 12.
Article in English | MEDLINE | ID: covidwho-1676706

ABSTRACT

BACKGROUND: The COVID-19 pandemic disrupted the normal delivery of HIV care, altered social support networks, and caused economic insecurity. People with HIV (PWH) are vulnerable to such disruptions, particularly if they have a history of substance use. We describe engagement in care and adherence to antiretroviral therapy (ART) for PWH during the pandemic. METHODS: From May 2020 to February 2021, 773 PWH enrolled in 6 existing cohorts completed 1495 surveys about substance use and engagement in HIV care during the COVID-19 pandemic. We described the prevalence and correlates of having missed a visit with an HIV provider in the past month and having missed a dose of ART in the past week. RESULTS: Thirteen percent of people missed an HIV visit in the past month. Missing a visit was associated with unstable housing, food insecurity, anxiety, low resiliency, disruptions to mental health care, and substance use including cigarette smoking, hazardous alcohol use, cocaine, and cannabis use. Nineteen percent of people reported missing at least one dose of ART in the week prior to their survey. Missing a dose of ART was associated with being a man, low resiliency, disruptions to mental health care, cigarette smoking, hazardous alcohol use, cocaine, and cannabis use, and experiencing disruptions to substance use treatment. CONCLUSIONS: Social determinants of health, substance use, and disruptions to mental health and substance use treatment were associated with poorer engagement in HIV care. Close attention to continuity of care during times of social disruption is especially critical for PWH.

7.
AIDS ; 36(3): 355-362, 2022 03 01.
Article in English | MEDLINE | ID: covidwho-1494133

ABSTRACT

OBJECTIVES: Telemedicine became the primary mode of delivering care during the COVID-19 pandemic. We describe the impact of telemedicine on access to care for people with HIV (PWH) by comparing the proportion of PWH engaged in care prior to and during the COVID-19 pandemic. DESIGN AND METHODS: We conducted an observational analysis of patients enrolled in the Johns Hopkins HIV Clinical Cohort, a single-center cohort of patients at an urban HIV subspecialty clinic affiliated with an academic center. Due to the COVID-19 pandemic, the clinic transitioned from in-person to mostly telemedicine visits. We compared patients receiving care in two time periods. The prepandemic period included 2010 people with at least one visit scheduled between 1 September 2019 and 15 March 2020. The pandemic period included 1929 people with at least one visit scheduled between 16 March 2020 and 30 September 2020. We determined the proportion of patients completing at least one of their scheduled visits during each period. RESULTS: Visit completion increased significantly from 88% prepandemic to 91% during the pandemic (P = 0.008). Visit completion improved significantly for patients age 20-39 (82 to 92%, P < 0.001), women (86 to 93%, P < 0.001), Black patients (88 to 91%, P = 0.002) and patients with detectable viremia (77 to 85%, P = 0.06) during the pandemic. Only 29% of people who completed at least one telemedicine visit during the pandemic did so as a video (versus telephone) visit. CONCLUSION: During the pandemic when care was widely delivered via telemedicine, visit completion improved among groups with lower prepandemic engagement but most were limited to telephone visits.


Subject(s)
COVID-19 , HIV Infections , Telemedicine , Adult , Female , Humans , Pandemics , SARS-CoV-2 , Young Adult
8.
J Clin Invest ; 130(6): 2757-2765, 2020 06 01.
Article in English | MEDLINE | ID: covidwho-38467

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), has spurred a global health crisis. To date, there are no proven options for prophylaxis for those who have been exposed to SARS-CoV-2, nor therapy for those who develop COVID-19. Immune (i.e., "convalescent") plasma refers to plasma that is collected from individuals following resolution of infection and development of antibodies. Passive antibody administration through transfusion of convalescent plasma may offer the only short-term strategy for conferring immediate immunity to susceptible individuals. There are numerous examples in which convalescent plasma has been used successfully as postexposure prophylaxis and/or treatment of infectious diseases, including other outbreaks of coronaviruses (e.g., SARS-1, Middle East respiratory syndrome [MERS]). Convalescent plasma has also been used in the COVID-19 pandemic; limited data from China suggest clinical benefit, including radiological resolution, reduction in viral loads, and improved survival. Globally, blood centers have robust infrastructure for undertaking collections and constructing inventories of convalescent plasma to meet the growing demand. Nonetheless, there are nuanced challenges, both regulatory and logistical, spanning donor eligibility, donor recruitment, collections, and transfusion itself. Data from rigorously controlled clinical trials of convalescent plasma are also few, underscoring the need to evaluate its use objectively for a range of indications (e.g., prevention vs. treatment) and patient populations (e.g., age, comorbid disease). We provide an overview of convalescent plasma, including evidence of benefit, regulatory considerations, logistical work flow, and proposed clinical trials, as scale-up is brought underway to mobilize this critical resource.


Subject(s)
Betacoronavirus , Coronavirus Infections/prevention & control , Coronavirus Infections/therapy , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Pneumonia, Viral/therapy , Antibodies, Viral/administration & dosage , Antibodies, Viral/blood , Antibodies, Viral/therapeutic use , Betacoronavirus/immunology , Blood Donors , COVID-19 , Coronavirus Infections/blood , Coronavirus Infections/epidemiology , Coronavirus Infections/immunology , Humans , Immunization, Passive/adverse effects , Investigational New Drug Application , Pneumonia, Viral/epidemiology , Risk Assessment , SARS-CoV-2 , United States , United States Food and Drug Administration , COVID-19 Serotherapy
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