COVID-19 Vaccination is Associated with Reduced Outpatient Antibiotic Prescribing In Older Adults with Confirmed SARS-CoV-2: A Population Wide Cohort Study.

BACKGROUND: Antibiotics are frequently prescribed unnecessarily in outpatients with COVID-19. We sought to evaluate factors associated with antibiotic prescribing in those with SARS-CoV-2 infection. METHODS: We performed a population-wide cohort study of outpatients 66 years or older with PCR-confirmed SARS-CoV-2 from January 1st 2020 to December 31st 2021 in Ontario, Canada. We determined rates of antibiotic prescribing within 1-week before (pre-diagnosis) and 1-week after (post-diagnosis) reporting of the positive SARS-CoV-2 result, compared to a self-controlled period (baseline). We evaluated predictors of prescribing, including a primary series COVID-19 vaccination, in univariate and multivariable analyses. RESULTS: We identified 13,529 eligible nursing home residents and 50,885 eligible community dwelling adults with SARS-CoV-2 infection. Of the nursing home and community residents, 3,020 (22%) and 6,372 (13%) received at least one antibiotic prescription within 1 week of a SARS-CoV-2 positive result, respectively. Antibiotic prescribing in nursing home and community residents occurred at 15.0 and 10.5 prescriptions per 1000 person-days pre-diagnosis and 20.9 and 9.8 per 1000 person-days post-diagnosis, higher than the baseline rates of 4.3 and 2.5 prescriptions per 1000 person-days. COVID-19 vaccination was associated with reduced prescribing in nursing home and community residents, with adjusted post-diagnosis IRRs of 0.7 (95%CI 0.4-1) and 0.3 (95%CI 0.3-0.4) respectively. CONCLUSIONS: Antibiotic prescribing was high and with little or no decline following SARS-CoV-2 diagnosis, though was reduced in COVID-19 vaccinated individuals, highlighting the importance of vaccination and antibiotic stewardship in older adults with COVID-19.

Evaluating the impact of a virtual outpatient care programme in preventing hospitalizations, emergency department visits and mortality for patients with COVID-19: a matched cohort study.

OBJECTIVES: To evaluate the impact of virtual care in preventing unnecessary healthcare visits for patients with SARS-CoV-2. METHODS: We conducted a retrospective matched cohort study, evaluating the COVID-19 Expansion to Outpatients (COVIDEO) programme involving virtual assessments for all positive patients in the Sunnybrook assessment centre from January 2020 to June 2021, followed by risk-stratified routine follow-up, couriering of oxygen saturation devices, and 24 hour/day direct-to-physician pager for urgent questions. We linked COVIDEO data to province-wide datasets, matching each eligible COVIDEO patient to ≤10 other Ontario SARS-CoV-2 patients on age, sex, neighbourhood, and date. The primary outcome was emergency department (ED) visit, hospitalization or death within 30 days. Multivariable regression accounted for comorbidities, vaccination, and pre-pandemic healthcare utilization. RESULTS: Among 6508 eligible COVIDEO patients, 4763 (73.1%) were matched to ≥1 non-COVIDEO patient. COVIDEO care was protective against the primary composite outcome (adjusted odds ratio [aOR] 0.91, 95% CI, 0.82-1.02), with a reduction in ED visits (7.8% vs. 9.6%; aOR 0.79, 95% CI, 0.70-0.89), but increase in hospitalizations (3.8% vs. 2.7%, aOR 1.37, 95% CI, 1.14-1.63) reflecting more direct-to-ward admissions (1.3% vs. 0.2%, p < 0.0001). Results were similar when matched comparators were limited to patients who had not received virtual care elsewhere with a decrease in ED visits (7.8 vs. 8.6%, aOR 0.86, 95% CI, 0.75-0.99) and an increase in hospitalizations (3.7 vs. 2.4%, aOR 1.45, 95% CI, 1.17-1.80). DISCUSSION: An intensive remote care programme can prevent unnecessary ED visits and facilitate direct-to-ward hospitalizations and thereby mitigate the impact of COVID-19 on the healthcare system.

Nursing home crowding and its association with outbreak-associated respiratory infection in Ontario, Canada before the COVID-19 pandemic (2014-19): a retrospective cohort study.

BACKGROUND: Studies conducted during the COVID-19 pandemic have shown that crowding in nursing homes is associated with high incidence of SARS-CoV-2 infections, but this effect has not been shown for other respiratory pathogens. We aimed to measure the association between crowding in nursing homes and outbreak-associated respiratory infection incidence and related mortality before the COVID-19 pandemic. METHODS: We conducted a retrospective cohort study of nursing homes in Ontario, Canada. We identified, characterised, and selected nursing homes through the Ontario Ministry of Long-Term Care datasets. Nursing homes that were not funded by the Ontario Ministry of Long-Term Care and homes that closed before January, 2020 were excluded. Outcomes consisting of respiratory infection outbreaks were obtained from the Integrated Public Health Information System of Ontario. The crowding index equalled the mean number of residents per bedroom and bathroom. The primary outcomes were the incidence of outbreak-associated infections and mortality per 100 nursing home residents per year. We examined the incidence of infections and deaths as a function of the crowding index by use of negative binomial regression with adjustment for three home characteristics (ie, ownership, number of beds, and region) and nine mean resident characteristics (ie, age, female sex, dementia, diabetes, chronic heart failure, renal failure, cancer, chronic obstructive pulmonary disease, and activities of daily living score). FINDINGS: Between Sept 1, 2014, and Aug 31, 2019, 5107 respiratory infection outbreaks in 588 nursing homes were recorded, of which 4921 (96·4%), involving 64 829 cases of respiratory infection and 1969 deaths, were included in this analysis. Nursing homes with a high crowding index had higher incidences of respiratory infection (26·4% vs 13·8%; adjusted rate ratio per one resident per room increase in crowding 1·89 [95% CI 1·64-2·17]) and mortality (0·8% vs 0·4%; 2·34 [1·88-2·92]) than did homes with a low crowding index. INTERPRETATION: Respiratory infection and mortality rates were higher in nursing homes with high crowding index than in homes with low crowding index, and the association was consistent across various respiratory pathogens. Decreasing crowding is an important safety target beyond the COVID-19 pandemic to help to promote resident wellbeing and decrease the transmission of prevalent respiratory pathogens. FUNDING: None.

Population-based evaluation of the effectiveness of nirmatrelvir-ritonavir for reducing hospital admissions and mortality from COVID-19.

BACKGROUND: A randomized controlled trial involving a high-risk, unvaccinated population that was conducted before the Omicron variant emerged found that nirmatrelvir-ritonavir was effective in preventing progression to severe COVID-19. Our objective was to evaluate the effectiveness of nirmatrelvir-ritonavir in preventing severe COVID-19 while Omicron and its subvariants predominate. METHODS: We conducted a population-based cohort study in Ontario that included all residents who were older than 17 years of age and had a positive polymerase chain reaction test for SARS-CoV-2 between Apr. 4 and Aug. 31, 2022. We compared patients treated with nirmatrelvir-ritonavir with patients who were not treated and measured the primary outcome of hospital admission from COVID-19 or all-cause death at 1-30 days, and a secondary outcome of all-cause death. We used weighted logistic regression to calculate weighted odds ratios (ORs) with confidence intervals (CIs) using inverse probability of treatment weighting (IPTW) to control for confounding. RESULTS: The final cohort included 177 545 patients, 8876 (5.0%) who were treated with nirmatrelvir-ritonavir and 168 669 (95.0%) who were not treated. The groups were well balanced with respect to demographic and clinical characteristics after applying stabilized IPTW. We found that the occurrence of hospital admission or death was lower in the group given nirmatrelvir-ritonavir than in those who were not (2.1% v. 3.7%; weighted OR 0.56, 95% CI 0.47-0.67). For death alone, the weighted OR was 0.49 (95% CI 0.39-0.62). Our findings were similar across strata of age, drug-drug interactions, vaccination status and comorbidities. The number needed to treat to prevent 1 case of severe COVID-19 was 62 (95% CI 43-80), which varied across strata. INTERPRETATION: Nirmatrelvir-ritonavir was associated with significantly reduced odds of hospital admission and death from COVID-19, which supports use to treat patients with mild COVID-19 who are at risk for severe disease.

Antibiotic resistance associated with the COVID-19 pandemic: a systematic review and meta-analysis.

BACKGROUND: COVID-19 and antimicrobial resistance (AMR) are two intersecting global public health crises. OBJECTIVE: We aimed to describe the impact of the COVID-19 pandemic on AMR across health care settings. DATA SOURCE: A search was conducted in December 2021 in WHO COVID-19 Research Database with forward citation searching up to June 2022. STUDY ELIGIBILITY: Studies evaluating the impact of COVID-19 on AMR in any population were included and influencing factors were extracted. Reporting of enhanced infection prevention and control and/or antimicrobial stewardship programs was noted. METHODS: Pooling was done separately for Gram-negative and Gram-positive organisms. Random-effects meta-analysis was performed. RESULTS: Of 6036 studies screened, 28 were included and 23 provided sufficient data for meta-analysis. The majority of studies focused on hospital settings (n = 25, 89%). The COVID-19 pandemic was not associated with a change in the incidence density (incidence rate ratio 0.99, 95% CI: 0.67-1.47) or proportion (risk ratio 0.91, 95% CI: 0.55-1.49) of methicillin-resistant Staphylococcus aureus or vancomycin-resistant enterococci cases. A non-statistically significant increase was noted for resistant Gram-negative organisms (i.e. extended-spectrum beta-lactamase, carbapenem-resistant Enterobacterales, carbapenem or multi-drug resistant or carbapenem-resistant Pseudomonas aeruginosa or Acinetobacter baumannii, incidence rate ratio 1.64, 95% CI: 0.92-2.92; risk ratio 1.08, 95% CI: 0.91-1.29). The absence of reported enhanced infection prevention and control and/or antimicrobial stewardship programs initiatives was associated with an increase in gram-negative AMR (risk ratio 1.11, 95% CI: 1.03-1.20). However, a test for subgroup differences showed no statistically significant difference between the presence and absence of these initiatives (p 0.40). CONCLUSION: The COVID-19 pandemic may have hastened the emergence and transmission of AMR, particularly for Gram-negative organisms in hospital settings. But there is considerable heterogeneity in both the AMR metrics used and the rate of resistance reported across studies. These findings reinforce the need for strengthened infection prevention, antimicrobial stewardship, and AMR surveillance in the context of the COVID-19 pandemic.

A cross-sectional study of hospital antimicrobial stewardship programmes in the COVID-19 era.

Background: Antimicrobial resistance (AMR) continues to be a global public health issue amid the COVID-19 pandemic; however, unprecedented demands on hospital antimicrobial stewardship programmes (ASPs) potentially altered their core activities. Objective: We sought to understand how ASPs have been involved in and impacted by the pandemic. Methods: The 2021 Ontario ASP Landscape Survey was developed based on previous provincial questionnaires and emerging literature on the impact of COVID-19 on hospital ASPs. After pre-testing and piloting, the online questionnaire was distributed to hospital antimicrobial stewardship practitioners in the fall of 2021. Descriptive statistics and inductive thematic analysis were performed. Results: The response rate was 78% (98/125 organizations); 96% (94/98) of organizations had or were in the process of formalizing an ASP and 53% (50/94) reported designated funding/resources. Despite 82% reporting no change in dedicated full-time equivalents during the pandemic, ASPs were frequently involved in developing treatment guidelines/clinical pathways (51%), anticipating/managing drug shortages (46%) and obtaining investigational use drugs (32%). While many core ASP activities continued, prospective audit and feedback and prescriber education were modified or suspended by 43% and 40% of programmes, respectively. Decreased frequency, adaptation of activities (i.e. virtual or other technology) and challenges with staffing/resources were commonly reported themes. Knowledge translation (KT) activities and 'collaboration and coordination' also emerged as salient themes. Conclusions: Hospital antimicrobial stewardship practitioners in Ontario have made significant contributions to the pandemic response while continuing to deliver adapted ASP services, despite resource constraints. Moving forward, ASPs will need to continue building capacity while leveraging broader networks to advance the antimicrobial stewardship agenda.

Antimicrobial resistance in patients with COVID-19: a systematic review and meta-analysis.

BACKGROUND: Frequent use of antibiotics in patients with COVID-19 threatens to exacerbate antimicrobial resistance. We aimed to establish the prevalence and predictors of bacterial infections and antimicrobial resistance in patients with COVID-19. METHODS: We did a systematic review and meta-analysis of studies of bacterial co-infections (identified within ≤48 h of presentation) and secondary infections (>48 h after presentation) in outpatients or hospitalised patients with COVID-19. We searched the WHO COVID-19 Research Database to identify cohort studies, case series, case-control trials, and randomised controlled trials with populations of at least 50 patients published in any language between Jan 1, 2019, and Dec 1, 2021. Reviews, editorials, letters, pre-prints, and conference proceedings were excluded, as were studies in which bacterial infection was not microbiologically confirmed (or confirmed via nasopharyngeal swab only). We screened titles and abstracts of papers identified by our search, and then assessed the full text of potentially relevant articles. We reported the pooled prevalence of bacterial infections and antimicrobial resistance by doing a random-effects meta-analysis and meta-regression. Our primary outcomes were the prevalence of bacterial co-infection and secondary infection, and the prevalence of antibiotic-resistant pathogens among patients with laboratory-confirmed COVID-19 and bacterial infections. The study protocol was registered with PROSPERO (CRD42021297344). FINDINGS: We included 148 studies of 362 976 patients, which were done between December, 2019, and May, 2021. The prevalence of bacterial co-infection was 5·3% (95% CI 3·8-7·4), whereas the prevalence of secondary bacterial infection was 18·4% (14·0-23·7). 42 (28%) studies included comprehensive data for the prevalence of antimicrobial resistance among bacterial infections. Among people with bacterial infections, the proportion of infections that were resistant to antimicrobials was 60·8% (95% CI 38·6-79·3), and the proportion of isolates that were resistant was 37·5% (26·9-49·5). Heterogeneity in the reported prevalence of antimicrobial resistance in organisms was substantial (I2=95%). INTERPRETATION: Although infrequently assessed, antimicrobial resistance is highly prevalent in patients with COVID-19 and bacterial infections. Future research and surveillance assessing the effect of COVID-19 on antimicrobial resistance at the patient and population level are urgently needed. FUNDING: WHO.

Ontario COVID-19 assessment centre practices in patient counselling, education, and follow-up care: A provincial survey.

Background: In March 2020, COVID-19 assessment centres were launched across the province of Ontario to facilitate COVID-19 testing outside of emergency departments. We aimed to study the degree to which assessment centres provide education and follow-up care for patients with suspected COVID-19. Methods: We conducted an online survey of Ontario COVID-19 assessment centre directors between September 15 and October 15, 2020. The primary outcomes studied were the types of educational modalities employed and information conveyed, methods and frequency of test result communication, and any follow-up care that was offered. Survey respondents were also asked to provide descriptions of barriers to patient education and test communication. Results: A total of 56 directors (representing 73 assessment centres) completed the survey. The most frequent educational modalities employed were educational handouts (92%), direct in-person counselling (89%), and referral to website (72%). Seventy-one percent of respondents indicated patients with positive test results would be notified, and 61% of respondents indicated that follow-up care would be offered. The most frequently reported barriers to patient education were insufficient time and high volume of tests, while the most frequently reported barriers to communication of test results were difficulty accessing online health portals and high volume of tests. Conclusion: The ability of many assessment centres to provide patient education is limited by both individual patient and system-level factors. Assessment centres may benefit from standardization of educational materials, improved accessibility to test results for patients in marginalized groups, and virtual pathways to facilitate additional counselling and care for individuals who test positive.

Historique : En mars 2020, des centres d'évaluation de la COVID-19 ont été lancés dans la province de l'Ontario afin de favoriser le dépistage de la COVID-19 hors des services d'urgence. Les chercheurs visaient à étudier dans quelle mesure ces centres transmettent de l'information et des soins de suivi aux patients chez qui on présume une COVID-19. Méthodologie : Les chercheurs ont réalisé un sondage en ligne auprès des directeurs des centres d'évaluation de la COVID-19 de l'Ontario entre le 15 septembre et le 15 octobre 2020. Le type de modalités pédagogiques utilisé et d'information transmise, les modes et la fréquence de communication des résultats des tests et les soins de suivi offerts étaient les résultats cliniques primaires à l'étude. Les répondants au sondage ont également été invités à décrire les obstacles à la transmission d'information aux patients et à la communication des résultats. Résultats : Au total, 56 directeurs (représentant 73 centres d'évaluation) ont rempli le sondage. Les principales modalités pédagogiques étaient la remise de document d'information (92 %), des conseils individuels directs (89 %) et l'orientation vers un site Web (72 %). Ainsi, 71 % des répondants ont indiqué que les patients obtenant un résultat positif en étaient avisés, et 61 %, que des soins de suivi seraient offerts. Les principaux obstacles à la transmission d'information aux patients étaient le manque de temps et le volume élevé de tests, tandis que les principaux obstacles à la transmission des résultats étaient la difficulté d'accès aux portails santé en ligne et le volume élevé de tests. Conclusion : La capacité de nombreux centres d'évaluation à transmettre de l'information aux patients est limitée à la fois par des facteurs liés aux patients eux-mêmes et par des facteurs systémiques. Les centres d'évaluation pourraient tirer profit de la standardisation des documents pédagogiques, d'un meilleur accès aux résultats des tests pour les patients de groupes marginalisés et de trajectoires virtuelles pour favoriser la transmission de conseils et de soins supplémentaires aux personnes dont les résultats sont positifs.

Using Virtual Care to Facilitate Direct Hospital Admissions in Outpatients with Worsening COVID-19 Infection.

Recognizing emergency department overcrowding during the COVID-19 pandemic, a pathway to facilitate direct admissions for outpatients with worsening COVID-19 infection was created using the COVID-19 expansion to outpatients (COVIDEO) virtual care program. Outpatients appropriate for direct admission had oxygen saturations consistently <92% without severe respiratory distress. Pulse oximeters were proactively delivered to high-risk patients, and patients contacted the program in the event of worsening symptoms or desaturation persistently <92%. Over a 15-month period, 9,116 outpatients were managed by the program, 164 of whom were hospitalized, and 83 of those hospitalized (50.6%) were directly admitted through this pathway. Of those directly admitted, 10 (12.0%) patients required ICU admission, occurring a median of 4 days from hospital admission. The mortality rate among directly admitted patients was 3.6% (3/83). Implementation of a virtual care program to facilitate direct admissions in outpatients with COVID-19 created a safe, efficient, and patient-centered pathway of care.

Association between initial symptoms and subsequent hospitalization in outpatients with COVID-19: A cohort study

Background Most individuals with coronavirus disease 2019 (COVID-19) experience mild symptoms and are managed in the outpatient setting. The aim of this study was to determine whether self-reported symptoms at the time of diagnosis can identify patients at risk of clinical deterioration. Methods This was a retrospective cohort study of 671 outpatients with laboratory-confirmed COVID-19 diagnosed in Toronto between March 1 and October 16, 2020. We examined the association between patients’ baseline characteristics and self-reported symptoms at the time of diagnosis and the risk of subsequent hospitalization. Results Of 671 participants, 26 (3.9%) required hospitalization. Individuals aged 65 years or older were more likely to require hospitalization (odds ratio [OR] 5.29, 95% CI 2.19 to 12.77), whereas those without medical comorbidities were unlikely to be hospitalized (OR 0.02, 95% CI 0.00 to 0.17). After adjusting for age and presence of comorbidities, sputum production (adjusted OR [aOR] 5.01, 95% CI 1.97 to 12.75), arthralgias (aOR 4.82, 95% CI 1.85 to 12.53), diarrhea (aOR 4.56, 95% CI 1.82 to 11.42), fever (aOR 3.64, 95% CI 1.50 to 8.82), chills (aOR 3.62, 95% CI 1.54 to 8.50), and fatigue (aOR 2.59, 95% CI 1.04 to 6.47) were associated with subsequent hospitalization. Conclusions Early assessment of symptoms among outpatients with COVID-19 can help identify individuals at risk of clinical deterioration. Additional studies are needed to determine whether more intense follow-up and early intervention among high-risk individuals can alter the clinical trajectory of and outcomes among outpatients with COVID-19.

Post-acute health care burden after SARS-CoV-2 infection: a retrospective cohort study.

BACKGROUND: The post-acute burden of health care use after SARS-CoV-2 infection is unknown. We sought to quantify the post-acute burden of health care use after SARS-CoV-2 infection among community-dwelling adults in Ontario by comparing those with positive and negative polymerase chain reaction (PCR) test results for SARS-CoV-2 infection. METHODS: We conducted a retrospective cohort study involving community-dwelling adults in Ontario who had a PCR test between Jan. 1, 2020, and Mar. 31, 2021. Follow-up began 56 days after PCR testing. We matched people 1:1 on a comprehensive propensity score. We compared per-person-year rates for health care encounters at the mean and 99th percentiles, and compared counts using negative binomial models, stratified by sex. RESULTS: Among 531 702 matched people, mean age was 44 (standard deviation [SD] 17) years and 51% were female. Females who tested positive for SARS-CoV-2 had a mean of 1.98 (95% CI 1.63 to 2.29) more health care encounters overall per-person-year than those who had a negative test result, with 0.31 (95% CI 0.05 to 0.56) more home care encounters to 0.81 (95% CI 0.69 to 0.93) more long-term care days. At the 99th percentile per-person-year, females who tested positive had 6.48 more days of hospital admission and 28.37 more home care encounters. Males who tested positive for SARS-CoV-2 had 0.66 (95% CI 0.34 to 0.99) more overall health care encounters per-person-year than those who tested negative, with 0.14 (95% CI 0.06 to 0.21) more outpatient encounters and 0.48 (95% CI 0.36 to 0.60) long-term care days, and 0.43 (95% CI -0.67 to -0.21) fewer home care encounters. At the 99th percentile, they had 8.69 more days in hospital per-person-year, with fewer home care (-27.31) and outpatient (-0.87) encounters. INTERPRETATION: We found significantly higher rates of health care use after a positive SARS-CoV-2 PCR test in an analysis that matched test-positive with test-negative people. Stakeholders can use these findings to prepare for health care demand associated with post-COVID-19 condition (long COVID).

Neighbourhood-level socio-demographic characteristics and risk of COVID-19 incidence and mortality in Ontario, Canada: A population-based study.

OBJECTIVES: We aimed to estimate associations between COVID-19 incidence and mortality with neighbourhood-level immigration, race, housing, and socio-economic characteristics. METHODS: We conducted a population-based study of 28,808 COVID-19 cases in the provincial reportable infectious disease surveillance systems (Public Health Case and Contact Management System) which includes all known COVID-19 infections and deaths from Ontario, Canada reported between January 23, 2020 and July 28, 2020. Residents of congregate settings, Indigenous communities living on reserves or small neighbourhoods with populations <1,000 were excluded. Comparing neighbourhoods in the 90th to the 10th percentiles of socio-demographic characteristics, we estimated the associations between 18 neighbourhood-level measures of immigration, race, housing and socio-economic characteristics and COVID-19 incidence and mortality using Poisson generalized linear mixed models. RESULTS: Neighbourhoods with the highest proportion of immigrants (relative risk (RR): 4.0, 95%CI:3.5-4.5) and visible minority residents (RR: 3.3, 95%CI:2.9-3.7) showed the strongest association with COVID-19 incidence in adjusted models. Among individual race groups, COVID-19 incidence was highest among neighbourhoods with the high proportions of Black (RR: 2.4, 95%CI:2.2-2.6), South Asian (RR: 1.9, 95%CI:1.8-2.1), Latin American (RR: 1.8, 95%CI:1.6-2.0) and Middle Eastern (RR: 1.2, 95%CI:1.1-1.3) residents. Neighbourhoods with the highest average household size (RR: 1.9, 95%CI:1.7-2.1), proportion of multigenerational families (RR: 1.8, 95%CI:1.7-2.0) and unsuitably crowded housing (RR: 2.1, 95%CI:2.0-2.3) were associated with COVID-19 incidence. Neighbourhoods with the highest proportion of residents with less than high school education (RR: 1.6, 95%CI:1.4-1.8), low income (RR: 1.4, 95%CI:1.2-1.5) and unaffordable housing (RR: 1.6, 95%CI:1.4-1.8) were associated with COVID-19 incidence. Similar inequities were observed across neighbourhood-level sociodemographic characteristics and COVID-19 mortality. CONCLUSIONS: Neighbourhood-level inequities in COVID-19 incidence and mortality were observed in Ontario, with excess burden experienced in neighbourhoods with a higher proportion of immigrants, racialized populations, large households and low socio-economic status.

Prevalence and predictors of persistent post-COVID-19 symptoms.

BACKGROUND: The pandemic has affected hundreds of millions of people; early reports suggesting high rates of prolonged symptoms may be prone to selection bias. METHODS: In a program caring for all SARS-CoV-2 positive inpatients and outpatients between March to October 2020, and offering universal 90-day follow-up, we compared those who died prior to 90 days, not responding to follow-up, declining, or accepting follow-up. Among those seen or declining follow-up, we determined the prevalence and predictors of persistent symptoms. RESULTS: Among 993 patients, 21 (2.1%) died prior to 90 days, 506 (50.9%) did not respond, 260 (26.1%) declined follow-up because they were well, and 206 (20.7%) were fully assessed. Of 466 who responded to follow-up inquiry, 133 (28.5%) reported ≥1 persistent symptom, including constitutional (15.5%), psychiatric (14.2%), rheumatologic (13.1%), neurologic (13.1%), cardiorespiratory (12.0%), and gastrointestinal (1.7%). Predictors differed for each symptom type. Any persistent symptom was more common in older patients (adjusted odds ratio [aOR] 1.11, 95% CI 1.04 to 1.18/5 years), those diagnosed in hospital (aOR 2.03, 95% CI 1.24 to 3.33) and those with initial constitutional and rheumatologic symptoms. Patients not responding to follow-up were younger and healthier at baseline. CONCLUSION: Persistent symptoms are common and diverse 3 months post-COVID-19 but are likely over-estimated by most reports.

HISTORIQUE: La pandémie touche des centaines de millions de gens. Les rapports précoces laissant croire à des symptômes prolongés pourraient être assujettis à un biais de sélection. MÉTHODOLOGIE: Dans un programme de soins auprès de tous les patients ambulatoires et hospitalisés ayant reçu un résultat positif au SRAS-CoV-2 entre mars et octobre 2020, assorti d'un suivi universel de 90 jours, les chercheurs ont comparé les personnes qui ont succombé avant 90 jours, n'ont pas répondu au suivi ou ont décliné ou accepté le suivi. Chez celles qui ont été vues ou ont décliné le suivi, ils ont déterminé la prévalence et les prédicteurs de symptômes persistants. RÉSULTATS: Chez les 993 patients, 21 (2,1 %) sont décédés avant les 90 jours, 506 (50,9 %) n'ont pas répondu, 260 (26,1 %) ont décliné le suivi parce qu'ils se sentaient bien et 206 (20,7 %) se sont soumis à une évaluation complète. Des 466 qui ont répondu à l'offre de suivi, 133 (28,5 %) ont signalé ressentir au moins un symptôme persistant, y compris d'ordre constitutionnel (15,5 %), psychiatrique (14,2 %), rhumatologique (13,1 %), neurologique (13,1 %), cardiorespiratoire (12,0 %) et gastro-intestinal (1,7 %). Les prédicteurs différaient en fonction de chaque type de symptômes. Les symptômes persistants étaient courants chez les personnes âgées (rapport de cotes corrigé [RCc] 1,11, IC à 95 %, 1,04 à 1,18/cinq ans), les personnes diagnostiquées à l'hôpital (RCc 2,03, IC à 95 %, 1,24 à 3,33) et celles dont les manifestations initiales comportaient des symptômes constitutionnels et rhumatologiques. Les patients qui ne répondaient pas au suivi étaient plus jeunes et en meilleure santé au départ. CONCLUSION: Les symptômes persistants sont courants et diversifiés trois mois après la COVID-19, mais sont probablement surestimés dans la plupart des rapports.

A Time Series Analysis Evaluating Antibiotic Prescription Rates in Long-Term Care during the COVID-19 Pandemic in Alberta and Ontario, Canada.

The COVID-19 pandemic affected access to care, and the associated public health measures influenced the transmission of other infectious diseases. The pandemic has dramatically changed antibiotic prescribing in the community. We aimed to determine the impact of the COVID-19 pandemic and the resulting control measures on oral antibiotic prescribing in long-term care facilities (LTCFs) in Alberta and Ontario, Canada using linked administrative data. Antibiotic prescription data were collected for LTCF residents 65 years and older in Alberta and Ontario from 1 January 2017 until 31 December 2020. Weekly prescription rates per 1000 residents, stratified by age, sex, antibiotic class, and selected individual agents, were calculated. Interrupted time series analyses using SARIMA models were performed to test for changes in antibiotic prescription rates after the start of the pandemic (1 March 2020). The average annual cohort size was 18,489 for Alberta and 96,614 for Ontario. A significant decrease in overall weekly prescription rates after the start of the pandemic compared to pre-pandemic was found in Alberta, but not in Ontario. Furthermore, a significant decrease in prescription rates was observed for antibiotics mainly used to treat respiratory tract infections: amoxicillin in both provinces (Alberta: -0.6 per 1000 LTCF residents decrease in weekly prescription rate, p = 0.006; Ontario: -0.8, p < 0.001); and doxycycline (-0.2, p = 0.005) and penicillin (-0.04, p = 0.014) in Ontario. In Ontario, azithromycin was prescribed at a significantly higher rate after the start of the pandemic (0.7 per 1000 LTCF residents increase in weekly prescription rate, p = 0.011). A decrease in prescription rates for antibiotics that are largely used to treat respiratory tract infections is in keeping with the lower observed rates for respiratory infections resulting from pandemic control measures. The results should be considered in the contexts of different LTCF systems and provincial public health responses to the pandemic.

The Collapse of Infectious Disease Diagnoses Commonly Due to Communicable Respiratory Pathogens During the Coronavirus Disease 2019 Pandemic: A Time Series and Hierarchical Clustering Analysis.

Background: Nonpharmaceutical interventions such as physical distancing and mandatory masking were adopted in many jurisdictions during the coronavirus disease 2019 pandemic to decrease spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We determined the effects of these interventions on incidence of healthcare utilization for other infectious diseases. Methods: Using a healthcare administrative dataset, we employed an interrupted time series analysis to measure changes in healthcare visits for various infectious diseases across the province of Ontario, Canada, from January 2017 to December 2020. We used a hierarchical clustering algorithm to group diagnoses that demonstrated similar patterns of change through the pandemic months. Results: We found that visits for infectious diseases commonly caused by communicable respiratory pathogens (eg, acute bronchitis, acute sinusitis) formed distinct clusters from diagnoses that often originate from pathogens derived from the patient's own flora (eg, urinary tract infection, cellulitis). Moreover, infectious diagnoses commonly arising from communicable respiratory pathogens (hierarchical cluster 1: highly impacted diagnoses) were significantly decreased, with a rate ratio (RR) of 0.35 (95% confidence interval [CI], .30-.40; P < .001) after the introduction of public health interventions in April-December 2020, whereas infections typically arising from the patient's own flora (hierarchical cluster 3: minimally impacted diagnoses) did not demonstrate a sustained change in incidence (RR, 0.95 [95% CI, .90-1.01]; P = .085). Conclusions: Public health measures to curtail the incidence of SARS-CoV-2 were widely effective against other communicable respiratory infectious diseases with similar modes of transmission but had little effect on infectious diseases not strongly dependent on person-to-person transmission.

Screening Large Population Health Databases for Potential Coronavirus Disease 2019 Therapeutics: A Pharmacopeia-Wide Association Study of Commonly Prescribed Medications.

Background: For both the current and future pandemics, there is a need for high-throughput drug screening methods to identify existing drugs with potential preventive and/or therapeutic activity. Epidemiologic studies could complement laboratory-focused efforts to identify possible therapeutic agents. Methods: We performed a pharmacopeia-wide association study (PWAS) to identify commonly prescribed medications and medication classes that are associated with the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in older individuals (≥65 years) in long-term care homes (LTCHs) and the community, between 15 January 2020 and 31 December 2020, across the province of Ontario, Canada. Results: A total of 26 121 cases and 2 369 020 controls from LTCHs and the community were included in this analysis. Many of the drugs and drug classes evaluated did not yield significant associations with SARS-CoV-2 detection. However, some drugs and drug classes appeared to be significantly associated with reduced SARS-CoV-2 detection, including cardioprotective drug classes such as statins (weighted odds ratio [OR], 0.91; standard P < .01, adjusted P < .01) and ß-blockers (weighted OR, 0.87; standard P < .01, adjusted P = .01), along with individual agents ranging from levetiracetam (weighted OR, 0.70; standard P < .01, adjusted P < .01) to fluoxetine (weighted OR, 0.86; standard P = .013, adjusted P = .198) to digoxin (weighted OR, 0.89; standard P < .01, adjusted P = .02). Conclusions: Using this epidemiologic approach, which can be applied to current and future pandemics, we have identified a variety of target drugs and drug classes that could offer therapeutic benefit in coronavirus disease 2019 (COVID-19) and may warrant further validation. Some of these agents (eg, fluoxetine) have already been identified for their therapeutic potential.

Screening Large Population Health Databases for Potential COVID-19 Therapeutics: A Pharmacopeia-Wide Association Study (PWAS) of Commonly Prescribed Medications

Background For both the current and future pandemics, there is a need for high-throughput drug screening methods to identify existing drugs with potential preventative and/or therapeutic activity. Epidemiologic studies could complement lab-focused efforts to identify possible therapeutic agents. Methods We performed a pharmacopeia-wide association study (PWAS) to identify commonly prescribed medications and medication classes that are associated with the detection of SARS-CoV-2 in older individuals (>65 years) in long-term care homes (LTCH) and the community, between January 15 th, 2020 and December 31 st, 2020, across the province of Ontario, Canada. Results 26,121 cases and 2,369,020 controls from LTCH and the community were included in this analysis. Many of the drugs and drug classes evaluated did not yield significant associations with SARS-CoV-2 detection. However, some drugs and drug classes appeared significantly associated with reduced SARS-CoV-2 detection, including cardioprotective drug classes such as statins (weighted OR 0.91, standard p-value <0.01, adjusted p-value <0.01) and beta-blockers (weighted OR 0.87, standard p-value <0.01, adjusted p-value 0.01), along with individual agents ranging from levetiracetam (weighted OR 0.70, standard p-value <0.01, adjusted p-value <0.01) to fluoxetine (weighted OR 0.86, standard p-value 0.013, adjusted p-value 0.198) to digoxin (weighted OR 0.89, standard p-value <0.01, adjusted p-value 0.02). Conclusions Using this epidemiologic approach which can be applied to current and future pandemics we have identified a variety of target drugs and drug classes that could offer therapeutic benefit in COVID-19 and may warrant further validation. Some of these agents (e.g. fluoxetine) have already been identified for their therapeutic potential.

Resident physicians' perceptions of COVID-19 risk.

BACKGROUND: Resident physicians provide front-line care to coronavirus disease 2019 (COVID-19) patients, but little is known about how they perceive the risk to their own health or how this is affected by the increasing role of social media in disseminating information. This study aims to determine resident physicians' perceptions of personal COVID-19 risk during the first COVID wave and compare risk perceptions between low-average and high social media users. METHODS: We conducted a cross-sectional survey at the University of Toronto in May 2020 among resident physicians in internal medicine, emergency medicine, critical care, and anaesthesia. Participants were considered high social media users if above the median for daily social media use and low-average users if at or below the median. The primary outcome was perceived risk of hospitalization with COVID-19 within 6 months. RESULTS: A total of 98 resident physicians reported a median of 1-2 hours daily on social media, and 55.7% endorsed social media as a very or the most common source of information on COVID-19. The median overall perceived risk of hospitalization was 10% (inter-quartile range [IQR] 5-25)-7.5% for low-average social media users and 17.5% for high social media users (p = 0.10). CONCLUSIONS: Resident physicians have an elevated perception of COVID-19 risk, including a perceived risk of hospitalization 250 times greater than the local population risk. Although social media are an important source of information on COVID-19, risk perception did not significantly differ between high and low-average social media users.

HISTORIQUE: Les résidents en médecine donnent des soins de première ligne aux patients atteints de la maladie à coronavirus 2019 (COVID-19), mais on possède peu d'information au sujet de la perception de leur risque personnel ou de l'effet de la diffusion croissante d'information et de désinformation dans les réseaux sociaux sur leur perception. La présente étude vise à déterminer les perceptions du risque personnel de COVID-19 chez les résidents en médecine pendant la première vague de la pandémie et à comparer les perceptions de risque entre les utilisateurs faibles à modérés et les grands utilisateurs des réseaux sociaux. MÉTHODOLOGIE: En mai 2020, les chercheurs ont réalisé une étude transversale auprès des résidents en médecine interne, en médecine d'urgence, en soins intensifs et en anesthésie de l'Université de Toronto. Ceux qui se situaient au-dessus de la médiane d'utilisation quotidienne des réseaux sociaux étaient considérés comme de grands utilisateurs des réseaux sociaux, et ceux qui se situaient sur ou sous la médiane, comme des utilisateurs faibles ou modérés. Le résultat clinique primaire était le risque perçu d'hospitalisation à cause de la COVID-19 dans les six mois, et les résultats cliniques secondaires, le risque estimatif de contracter la COVID-19 ou d'infecter des membres de la famille, le degré d'anxiété au sujet de la COVID-19 et les répercussions perçues de l'hospitalisation. RÉSULTATS: Au total, 98 résidents en médecine ont déclaré consacrer une médiane de une à deux heures par jour aux réseaux sociaux, et 55,7 % considéraient les réseaux sociaux comme leur principale source d'information ou une source d'information très importante sur la COVID-19. Le risque médian perçu de contracter la COVID-19 s'élevait à 60 % (ratio interquartile [RIQ] 32 à 75), d'être hospitalisé, à 10 % (RIQ 5 à 25), et d'infecter des membres de la famille, à 37 % (RIQ 10,5 à 60). Le risque médian perçu d'hospitalisation s'élevait à 7,5 % pour les utilisateurs faibles ou modérés des réseaux sociaux, et à 17,5 % pour les grands utilisateurs des réseaux sociaux (p = 0,10). CONCLUSIONS: Les résidents en médecine ont une perception élevée du risque de COVID-19, y compris une perception du risque d'hospitalisation 250 fois plus élevée que celle de la population locale. Même si les médias sociaux représentent une source importante d'information sur la COVID-19 pour les résidents en médecine, la perception du risque ne différait pas de manière significative entre les grands utilisateurs et les faibles utilisateurs des réseaux sociaux.