July 13, 2023

Clinical Reports

  • Exaggerated blood pressure elevation in response to orthostatic challenge, a post-acute sequelae of SARS-CoV-2 infection (PASC) after hospitalization
    • Post-acute sequelae of SARS-COV-2 (PASC) are emerging as a major health challenge. Orthostatic intolerance secondary to autonomic failure has been found in PASC patients. This study investigated the effect of COVID-19 after recovery on blood pressure (BP) during the orthostatic challenge. Thirty-one out of 45 patients hospitalized due to COVID-19-related pneumonia that developed PASC and did not have hypertension at discharge were studied. They underwent a head-up tilt test (HUTT) at 10.8 ± 1.9 months from discharge. All met the PASC clinical criteria, and an alternative diagnosis did not explain the symptoms. This population was compared with 32 historical asymptomatic healthy controls. Exaggerated orthostatic blood pressure response (EOPR)/orthostatic hypertension (OHT) was detected in 8 out of 23 (34.7 %) patients, representing a significantly increased prevalence (7.67-fold increase p = 0.009) compared to 2 out of 32 (6.4 %) asymptomatic healthy controls matched by age, who underwent HUTT and were not infected with SARS-CoV-2.This prospective evaluation in patients with PASC revealed abnormal blood pressure rise during the orthostatic challenge, suggesting of autonomic dysfunction in a third of the studied subjects. These findings support the hypothesis that EOPR/OHT may be a phenotype of neurogenic hypertension. Hypertension in PASC patients may adversely affect the cardiovascular burden in the world.
  • Long term follow-up of a multicentre cohort of COVID-19 patients with pulmonary embolism: Anticoagulation management and outcomes
    • Pulmonary embolism (PE) is a frequent complication in COVID19 hospitalized patients. Inflammatory storm and endothelial dysfunction due to the virus seem to be the two major risk factors for PE. Consequently, PE related to COVID19 could be consider as triggered by a transient inflammatory acute phase and treated for no longer than 3 months. However, few data are available on management of anticoagulation and risk of venous thromboembolic (VTE) recurrences in these patients and guidelines are still undefined. Researchers conducted a retrospective multicenter study in four Italian hospitals between March 1st, 2020, and May 31st, 2021 in patients who experienced a PE during hospitalization for a COVID-19 pneumonia, excluding patients who died during hospitalization. Baseline characteristics were collected and patients were grouped according to duration of anticoagulant treatment (< 3 months or > 3 months). The primary outcome was incidence of VTE recurrence while secondary outcome was the composite of deaths, major hemorrhages and VTE recurrence during follow-up. 106 patients with PE were discharged, of these 95 (89.6 %) had follow up longer than 3 months (seven patients were lost to follow up and four died within three months). The median follow-up was 13 months (IQR 1–19). Overall, 23 % of subjects (22/95) were treated for 3 months or less and 76.8 % (73/95) received anticoagulation for >3 months. Of patients in the short treatment group, 4.5 % died, compared with 5.5 % of those in the longer treatment group (p = NS); no difference was shown in risk of VTE recurrence (0 % vs 4.1 %, p = NS), major bleeding (4.5 % vs 4.1 %, p = NS) or in composite outcome (9.1 % vs 11 %, p = NS).

Antiviral Therapeutics and Vaccines

  • Development of monoclonal antibody-based blocking ELISA for detecting SARS-CoV-2 exposure in animals
    • The global pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a significant threat to public health. Besides humans, SARS-CoV-2 can infect several animal species. Highly sensitive and specific diagnostic reagents and assays are urgently needed for rapid detection and implementation of strategies for prevention and control of the infection in animals. In this study, researchers initially developed a panel of monoclonal antibodies (mAbs) against SARS-CoV-2 nucleocapsid protein. To detect SARS-CoV-2 antibodies in a broad spectrum of animal species, an mAb-based blocking enzyme-linked immunosorbent assay (bELISA) was developed. Test validation using a set of animal serum samples with known infection status obtained an optimal percentage of inhibition cut-off value of 17.6% with diagnostic sensitivity of 97.8% and diagnostic specificity of 98.9%. The assay demonstrates high repeatability as determined by a low coefficient of variation (7.23%, 4.89%, and 3.16%) between-runs, within-run, and within-plate, respectively. Testing of samples collected over time from experimentally infected cats showed that the bELISA was able to detect seroconversion as early as 7 days post-infection. Subsequently, the bELISA was applied for testing pet animals with coronavirus disease 2019 (COVID-19)-like symptoms and specific antibody responses were detected in two dogs. The panel of mAbs generated in this study provides a valuable tool for SARS-CoV-2 diagnostics and research. The mAb-based bELISA provides a serological test in aid of COVID-19 surveillance in animals.
  • Repeated antibiotic exposure and risk of hospitalization and death following COVID-19 infection
    • With the approval of NHS England, researchers used the OpenSAFELY platform, which integrated primary and secondary care, COVID-19 test, and death registration data. This matched case–control study included 0.67 million patients (aged 18–110 years) from an eligible 2.47 million patients with incident COVID-19 by matching with replacement. Inclusion criteria included registration within one general practice for at least 3 years and infection with incident COVID-19. Cases were identified according to different severity of COVID-19 outcomes. Cases and eligible controls were 1:6 matched on age, sex, region of GP practice, and index year and month of COVID-19 infection. Five quintile groups, based on the number of previous 3-year antibiotic prescriptions, were created to indicate the frequency of prior antibiotic exposure. Conditional logistic regression used to compare the differences between case and control groups, adjusting for ethnicity, body mass index, comorbidities, vaccination history, deprivation, and care home status. Sensitivity analyses were done to explore potential confounding and the effects of missing data. Based on our inclusion criteria, between February 1, 2020 and December 31, 2021, 98,420 patients were admitted to hospitals and 22,660 died. 55 unique antibiotics were prescribed. A dose–response relationship between number of antibiotic prescriptions and risk of severe COVID-19 outcome was observed. Patients in the highest quintile with history of prior antibiotic exposure had 1.80 times greater odds of hospitalization compared to patients without antibiotic exposure (adjusted odds ratio [OR] 1.80, 95% Confidence Interval [CI] 1.75–1.84). Similarly, the adjusted OR for hospitalized patients with death outcomes was 1.34 (95% CI 1.28–1.41). Larger number of prior antibiotic type was also associated with more severe COVID-19 related hospital admission. The adjusted OR of quintile 5 exposure (the most frequent) with more than 3 antibiotic types was around 2 times larger than quintile 1 (only 1 type; OR 1.80, 95% CI 1.75–1.84 vs. OR 1.03, 95% CI 1.01–1.05). This observational study has provided evidence that antibiotic exposure frequency and diversity may be associated with COVID-19 severity, potentially suggesting adverse effects of repeated intermittent antibiotic use. Future work could work to elucidate causal links and potential mechanisms. Antibiotic stewardship should put more emphasis on long-term antibiotic exposure and its adverse outcome to increase the awareness of appropriate antibiotics use. 


  • The Coronavirus Disease 2019 Rebound Study: A Prospective Cohort Study to Evaluate Viral and Symptom Rebound Differences in Participants Treated With Nirmatrelvir Plus Ritonavir Versus Untreated Controls
    • The uptake of nirmatrelvir plus ritonavir (NPR) in patients with coronavirus disease 2019 (COVID-19) has been limited by concerns around the rebound phenomenon despite the scarcity of evidence around its epidemiology. The purpose of this study was to prospectively compare the epidemiology of rebound in NPR-treated and untreated participants with acute COVID-19 infection. Researchers designed a prospective, observational study in which participants who tested positive for COVID-19 and were clinically eligible for NPR were recruited to be evaluated for either viral or symptom clearance and rebound. Participants were assigned to the treatment or control group based on their decision to take NPR. Following initial diagnosis, both groups were provided 12 rapid antigen tests and asked to test on a regular schedule for 16 days and answer symptom surveys. Viral rebound based on test results and COVID-19 symptom rebound based on patient-reported symptoms were evaluated. Viral rebound incidence was 14.2% in the NPR treatment group (n = 127) and 9.3% in the control group (n = 43). Symptom rebound incidence was higher in the treatment group (18.9%) compared to controls (7.0%). There were no notable differences in viral rebound by age, gender, preexisting conditions, or major symptom groups during the acute phase or at the 1-month interval. This preliminary report suggests that rebound after clearance of test positivity or symptom resolution is higher than previously reported. However, notably researchers observed a similar rate of rebound in both the NPR treatment and control groups. Large studies with diverse participants and extended follow-up are needed to better understand the rebound phenomena.
  • Risk of Cardiovascular Disease After COVID19 Diagnosis Among Adults With and Without Diabetes
    • Growing evidence suggests incident cardiovascular disease (CVD) may be a longterm outcome of COVID19 infection, and chronic diseases, such as diabetes, may influence CVD risk associated with COVID19. Researchers evaluated the postacute risk of CVD >30 days after a COVID19 diagnosis by diabetes status. Researchers included adults ≥20 years old with a COVID19 diagnosis from March 1, 2020 through December 31, 2021 in a retrospective cohort study from the IQVIA PharMetrics Plus insurance claims database. A contemporaneous control group comprised adults without recorded diagnoses for COVID19 or other acute respiratory infections. Two historical control groups comprised patients with or without an acute respiratory infection. Cardiovascular outcomes included cerebrovascular disorders, dysrhythmia, inflammatory heart disease, ischemic heart disease, thrombotic disorders, other cardiac disorders, major adverse cardiovascular events, and any CVD. The total sample comprised 23 824 095 adults (mean age, 48.4 years [SD, 15.7 years]; 51.9% women; mean followup, 8.5 months [SD, 5.8 months]). In multivariable Cox regression models, patients with a COVID19 diagnosis had a significantly greater risk of all cardiovascular outcomes compared with patients without a diagnosis of COVID19 (hazard ratio [HR], 1.66 [1.62–1.71], with diabetes; HR, 1.75 [1.73–1.78], without diabetes). Risk was attenuated but still significant for the majority of outcomes when comparing patients with COVID19 to both historical control groups. In patients with COVID19 infection, postacute risk of incident cardiovascular outcomes is significantly higher than among controls without COVID19, regardless of diabetes status. Therefore, monitoring for incident CVD may be essential beyond the first 30 days after a COVID19 diagnosis.

Situation Dashboards


World Health Organization (WHO)

Novel Coronavirus (COVID-19) Situation from World Health Organization (WHO)

Johns Hopkins University (JHU)

Coronavirus COVID-19 Global Cases by the Center for Systems Science and Engineering (CSSE) at JHU

COVID-19 in US and Canada

1Point3Acres Real-Time Coronavirus (COVID-19) Updates in US and Canada with Credible Sources

Genomic Epidemiology COVID-19

Genomic Epidemiology of (COVID-19) Maintained by the Nextstrain team, enabled by data from GISAID.

Sources for COVID-19 Information


World Health Organization (WHO)


Centers for Disease Control, US


International Society for Infectious Diseases


This Week in Virology (TWIV)

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