Protection Conferred by COVID-19 Vaccination, Prior SARS-CoV-2 Infection, or Hybrid Immunity Against Omicron-Associated Severe Outcomes Among Community-Dwelling Adults

INTRODUCTION

We assessed protection from coronavirus disease 2019 (COVID-19) vaccines and/or prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection against Omicron-associated severe outcomes during successive sublineage-predominant periods.

METHODS

We used a test-negative design to estimate protection by vaccines and/or prior infection against hospitalization/death among community-dwelling, polymerase chain reaction (PCR)-tested adults aged ≥50 years in Ontario, Canada, between 2 January 2022 and 30 June 2023. Multivariable logistic regression was used to estimate the relative change in the odds of hospitalization/death with each vaccine dose (2-5) and/or prior PCR-confirmed SARS-CoV-2 infection (compared with unvaccinated, uninfected subjects) up to 15 months since the last vaccination or infection.

RESULTS

We included 18 526 cases with Omicron-associated severe outcomes and 90 778 test-negative controls. Vaccine protection was high during BA.1/BA.2 predominance but was generally <50% during periods of BA.4/BA.5 and BQ/XBB predominance without boosters. A third/fourth dose transiently increased protection during BA.4/BA.5 predominance (third-dose, 6-month: 68%, 95% confidence interval [CI] 63%-72%; fourth-dose, 6-month: 80%, 95% CI 77%-83%) but was lower and waned quickly during BQ/XBB predominance (third-dose, 6-month: 59%, 95% CI 48%-67%; 12-month: 49%, 95% CI 41%-56%; fourth-dose, 6-month: 62%, 95% CI 56%-68%, 12-months: 51%, 95% CI 41%-56%). Hybrid immunity conferred nearly 90% protection throughout BA.1/BA.2 and BA.4/BA.5 predominance but was reduced during BQ/XBB predominance (third-dose, 6-month: 60%, 95% CI 36%-75%; fourth-dose, 6-month: 63%, 95% CI 42%-76%). Protection was restored with a fifth dose (bivalent; 6-month: 91%, 95% CI 79%-96%). Prior infection alone did not confer lasting protection.

CONCLUSIONS

Protection from COVID-19 vaccines and/or prior SARS-CoV-2 infections against severe outcomes is reduced when immune-evasive variants/subvariants emerge and may also wane over time. Our findings support a variant-adapted booster vaccination strategy with periodic review.

Effectiveness of mRNA COVID-19 Monovalent and Bivalent Vaccine Booster Doses Against Omicron Severe Outcomes Among Adults Aged ≥50 Years in Ontario, Canada: A Canadian Immunization Research Network Study

We estimated the effectiveness of booster doses of monovalent and bivalent mRNA COVID-19 vaccines against Omicron-associated severe outcomes among adults aged ≥50 years in Ontario, Canada. Monovalent and bivalent mRNA COVID-19 booster doses provided similar strong initial protection against severe outcomes. Uncertainty remains around waning of protection from these vaccines.

A portable primary-standard level graphite calorimeter for absolute dosimetry in clinical pencil beam scanning proton beams

Objective. To report the use of a portable primary standard level graphite calorimeter for direct dose determination in clinical pencil beam scanning proton beams, which forms part of the recommendations of the proposed Institute of Physics and Engineering in Medicine (IPEM) Code of Practice (CoP) for proton therapy dosimetry.Approach. The primary standard proton calorimeter (PSPC) was developed at the National Physical Laboratory (NPL) and measurements were performed at four clinical proton therapy facilities that use pencil beam scanning for beam delivery. Correction factors for the presence of impurities and vacuum gaps were calculated and applied, as well as dose conversion factors to obtain dose to water. Measurements were performed in the middle of 10 × 10 × 10 cm3homogeneous dose volumes, centred at 10.0, 15.0 and 25.0 g·cm-2depth in water. The absorbed dose to water determined with the calorimeter was compared to the dose obtained using PTW Roos-type ionisation chambers calibrated in terms of absorbed dose to water in60Co applying the recommendations in the IAEA TRS-398 CoP.Main results.The relative dose difference between the two protocols varied between 0.4% and 2.1% depending on the facility. The reported overall uncertainty in the determination of absorbed dose to water using the calorimeter is 0.9% (k= 1), which corresponds to a significant reduction of uncertainty in comparison with the TRS-398 CoP (currently with an uncertainty equal or larger than 2.0% (k= 1) for proton beams).Significance. The establishment of a purpose-built primary standard and associated CoP will considerably reduce the uncertainty of the absorbed dose to water determination and ensure improved accuracy and consistency in the dose delivered to patients treated with proton therapy and bring proton reference dosimetry uncertainty in line with megavoltage photon radiotherapy.

Alanine response to low energy synchrotron x-ray radiation

Objective. The radiation response of alanine is very well characterized in the MV photon energy range where it can be used to determine the dose delivered with an accuracy better than 1%, making it suitable as a secondary standard detector in cancer radiation therapy. This is not the case in the very low energy keV x-ray range where the alanine response is affected by large uncertainties and is strongly dependent on the x-ray beam energy. This motivated the study undertaken here.Approach. Alanine pellets with a nominal thickness of 0.5 mm and diameter of 5 mm were irradiated with monoenergetic x-rays at the Diamond Light Source synchrotron, to quantify their response in the 8-20 keV range relative to60Co radiation. The absorbed dose to graphite was measured with a small portable graphite calorimeter, and the DOSRZnrc code in the EGSnrc Monte Carlo package was used to calculate conversion factors between the measured dose to graphite and the absorbed dose to water delivered to the alanine pellets. GafChromic EBT3 films were used to measure the beam profile for modelling in the MC simulations.Main results. The relative responses measured in this energy range were found to range from 0.616 to 0.643, with a combined relative expanded uncertainty of 3.4%-3.5% (k= 2), where the majority of the uncertainty originated from the uncertainty in the alanine readout, due to the small size of the pellets used.Significance. The measured values were in good agreement with previously published data in the overlapping region of x-ray energies, while this work extended the dataset to lower energies. By measuring the response to monoenergetic x-rays, the response to a more complex broad-spectrum x-ray source can be inferred if the spectrum is known, meaning that this work supports the establishment of alanine as a secondary standard dosimeter for low-energy x-ray sources.

Cost-effectiveness of remdesivir plus usual care versus usual care alone for hospitalized patients with COVID-19: an economic evaluation as part of the Canadian Treatments for COVID-19 (CATCO) randomized clinical trial

BACKGROUND

The role of remdesivir in the treatment of hospitalized patients with COVID-19 remains ill-defined. We conducted a cost-effectiveness analysis alongside the Canadian Treatments for COVID-19 (CATCO) open-label, randomized clinical trial evaluating remdesivir.

METHODS

Patients with COVID-19 in Canadian hospitals from Aug. 14, 2020, to Apr. 1, 2021, were randomly assigned to receive remdesivir plus usual care versus usual care alone. Taking a public health care payer's perspective, we collected in-hospital outcomes and health care resource utilization alongside estimated unit costs in 2020 Canadian dollars over a time horizon from randomization to hospital discharge or death. Data from 1281 adults admitted to 52 hospitals in 6 Canadian provinces were analyzed.

RESULTS

The total mean cost per patient was $37 918 (standard deviation [SD] $42 413; 95% confidence interval [CI] $34 617 to $41 220) for patients randomly assigned to the remdesivir group and $38 026 (SD $46 021; 95% CI $34 480 to $41 573) for patients receiving usual care (incremental cost -$108 [95% CI -$4953 to $4737], p > 0.9). The difference in proportions of in-hospital deaths between remdesivir and usual care groups was -3.9% (18.7% v. 22.6%, 95% CI -8.3% to 1.0%, p = 0.09). The difference in proportions of incident invasive mechanical ventilation events between groups was -7.0% (8.0% v. 15.0%, 95% CI -10.6% to -3.4%, p = 0.006), whereas the difference in proportions of total mechanical ventilation events between groups was -5.7% (16.4% v. 22.1%, 95% CI -10.0% to -1.4%, p = 0.01). Remdesivir was the dominant intervention (but only marginally less costly, with mildly lower mortality) with an incalculable incremental cost effectiveness ratio; we report results of incremental costs and incremental effects separately. For willingness-to-pay thresholds of $0, $20 000, $50 000 and $100 000 per death averted, a strategy using remdesivir was cost-effective in 60%, 67%, 74% and 79% of simulations, respectively. The remdesivir costs were the fifth highest cost driver, offset by shorter lengths of stay and less mechanical ventilation.

INTERPRETATION

From a health care payer perspective, treating patients hospitalized with COVID-19 with remdesivir and usual care appears to be preferrable to treating with usual care alone, albeit with marginal incremental cost and small clinical effects. The added cost of remdesivir was offset by shorter lengths of stay in the intensive care unit and less need for ventilation.

STUDY REGISTRATION

ClinicalTrials. gov, no. NCT04330690.

RSV-associated hospitalization in adults in the USA: A retrospective chart review investigating burden, management strategies, and outcomes

Background and Aims

The burden of respiratory syncytial virus (RSV) infection in adults is of growing concern. This study was designed to quantify disease burden, treatment approaches, and outcomes associated with RSV infections in adult subpopulations, from prehospitalization to hospital discharge.

Methods

A retrospective chart analysis was conducted to collect patient-case data from hospitalized US adults (aged >18 years) with RSV infection during two RSV seasons. Patients were categorized into risk groups: comorbid lung disease, immunocompromised, older adults (aged ≥65 years), and other adults (aged <65 years). Physicians reported diagnosis, treatment choices including respiratory supportive therapy (oxygen and fluid supplementation), and outcome variables using a standardized online case form.

Results

The majority (277/379; 73%) of patients presented to the emergency room, with a mean age of 60 years. Once hospitalized, the median length of stay was 6.0 days (3.0-9.0), with disease severity having the greatest impact on duration of stay. No significant between-group differences in rates of patients requiring management in intensive care units were found (comorbid lung disease, 28%; immunocompromised, 36%; older adults, 26%; and other adults, 23%). Overall, respiratory supportive therapy was the most commonly used form of treatment. Antibiotics were administered in over half of all risk groups (comorbid lung disease, 61%; immunocompromised, 59%; older adults, 59%; and other adults, 51%). Patients usually required follow-up visits following discharge, with 10%-16% requiring skilled nursing care and approximately 25% requiring assistance from a social worker.

Conclusion

RSV in adult subpopulations, irrespective of age, is a significant burden to healthcare systems.

The role of PLiM technologies in CANDU TM ongoing aging management, life extension, and new designs

This paper will discuss AECL’s approach in providing a comprehensive “full knowledge” support to plant ageing and ageing management. This requires the integration of research and development into safety, design, and service areas of the company. The paper will also explore how this integration is being accomplished through the initiatives of the PLiM program. The paper will examine several examples of how AECL is developing its understanding of ageing degradation, the engineered solutions, applying those solutions, improving those solutions, and finally incorporating these solutions into both the PLiM program and into new designs.

Remdesivir for the treatment of patients in hospital with COVID-19 in Canada: a randomized controlled trial

Background:

The role of remdesivir in the treatment of patients in hospital with COVID-19 remains ill defined in a global context. The World Health Organization Solidarity randomized controlled trial (RCT) evaluated remdesivir in patients across many countries, with Canada enrolling patients using an expanded data collection format in the Canadian Treatments for COVID-19 (CATCO) trial. We report on the Canadian findings, with additional demographics, characteristics and clinical outcomes, to explore the potential for differential effects across different health care systems.

Methods:

We performed an open-label, pragmatic RCT in Canadian hospitals, in conjunction with the Solidarity trial. We randomized patients to 10 days of remdesivir (200 mg intravenously [IV] on day 0, followed by 100 mg IV daily), plus standard care, or standard care alone. The primary outcome was in-hospital mortality. Secondary outcomes included changes in clinical severity, oxygen- and ventilator-free days (at 28 d), incidence of new oxygen or mechanical ventilation use, duration of hospital stay, and adverse event rates. We performed a priori subgroup analyses according to duration of symptoms before enrolment, age, sex and severity of symptoms on presentation.

Results:

Across 52 Canadian hospitals, we randomized 1282 patients between Aug. 14, 2020, and Apr. 1, 2021, to remdesivir (n = 634) or standard of care (n = 648). Of these, 15 withdrew consent or were still in hospital, for a total sample of 1267 patients. Among patients assigned to receive remdesivir, in-hospital mortality was 18.7%, compared with 22.6% in the standard-of-care arm (relative risk [RR] 0.83 (95% confidence interval [CI] 0.67 to 1.03), and 60-day mortality was 24.8% and 28.2%, respectively (95% CI 0.72 to 1.07). For patients not mechanically ventilated at baseline, the need for mechanical ventilation was 8.0% in those assigned remdesivir, and 15.0% in those receiving standard of care (RR 0.53, 95% CI 0.38 to 0.75). Mean oxygen-free and ventilator-free days at day 28 were 15.9 (± standard deviation [SD] 10.5) and 21.4 (± SD 11.3) in those receiving remdesivir and 14.2 (± SD 11) and 19.5 (± SD 12.3) in those receiving standard of care (p = 0.006 and 0.007, respectively). There was no difference in safety events of new dialysis, change in creatinine, or new hepatic dysfunction between the 2 groups.

Interpretation:

Remdesivir, when compared with standard of care, has a modest but significant effect on outcomes important to patients and health systems, such as the need for mechanical ventilation. Trial registration: ClinicalTrials.gov, no. NCT04330690.

Decline of Influenza and Respiratory Viruses With COVID-19 Public Health Measures: Alberta, Canada

OBJECTIVE

To determine the incidence of influenza and noninfluenza respiratory viruses (NIRVs) pre-/post-implementation of public health measures aimed to decrease coronavirus disease 2019 (COVID-19) transmission using population-based surveillance data. We hypothesized that such measures could reduce the burden of respiratory viruses (RVs) transmitting via the same routes.

PATIENTS AND METHODS

An interrupted time-series analysis of RV surveillance data in Alberta, Canada, from May 2017 to July 2020 was conducted. The burden of influenza and NIRVs before and after intervention initiation at week 11 was compared. The analysis was adjusted for seasonality, overdispersion, and autocorrelation.

RESULTS

During the study period, an average of 708 and 4056 weekly respiratory multiplex molecular panels were conducted pre-/post-intervention, respectively. We found significant reductions in test positivity rates in the postintervention period for influenza (-94.3%; 95% CI, -93.8 to 97.4%; P<.001) and all NIRVs (-76.5%; 95% CI, -77.3 to -75.8%; P<.001) in the crude model, and -86.2% (95% CI, -91.5 to -77.4%: P<.001) and -75% (95% CI, -79.7 to -69.3%; P<.001), respectively, in the adjusted models. Subanalyses for individual viruses showed significant decreases in respiratory syncytial virus, human metapneumovirus, enterovirus/rhinovirus, and parainfluenza. For non-severe acute respiratory coronavirus 2 human coronaviruses, the decline was not statistically significant after adjustment (-22.3%; 95% CI, -49.3 to +19%, P=.246).

CONCLUSION

The implementation of COVID-19 public health measures likely resulted in reduced transmission of common RVs. Although drastic lockdowns are unlikely to be required given widespread COVID-19 vaccination, targeted implementation of such measures can lower RV disease burden. Studies to evaluate relative contributions of individual interventions are warranted.

Outcomes among critically ill adults with influenza infection

Background

Influenza infection is a major cause of mortality in critical care units.

Methods

ata on critically ill adult patients with influenza infection from 2014 to 2019 were retrospectively collected, including mortality and critical care resource utilization. Independent predictors of mortality were identified using Cox regression.

Results

ne hundred thirty patients with confirmed influenza infection had a mean age of 56 (SD 16) years; 72 (55%) were male. Mean Acute Physiology and Chronic Health Evaluation (APACHE II) score was 22 (SD 9). One hundred eight (83%) patients had influenza A (46% H1N1pdm09, 33% H3N2); 21 (16%) had influenza B. Fifty-five (42%) patients had bacterial co-infection. Only 5 (4%) had fungal co-infection. One hundred eight (83%) patients required mechanical ventilation; 94 (72%), vasopressor support; 26 (20%), continuous renal replacement therapy (CRRT); and 11 (9%), extracorporeal membrane oxygenation. One hundred twenty one (93%) patients received antiviral therapy (median 5 d). Thirty-day mortality was 23%. Patients who received antiviral treatment were more likely to survive with an adjusted hazard ratio (aHR) of 0.15 (95% CI 0.04 to 0.51, p = 0.003). Other independent predictors of mortality were the need for CRRT (aHR 2.48, 95% CI 1.14 to 5.43, p = 0.023), higher APACHE II score (aHR 1.08, 95% CI 1.02 to 1.14, p = 0.011), and influenza A (aHR 7.10, 95% CI 1.37 to 36.8, p = 0.020) compared with influenza B infection.

Conclusions

mong critically ill influenza patients, antiviral therapy was independently associated with survival. CRRT, higher severity of illness, and influenza A infection were associated with mortality.

The swelling behavior of the mouse cervix: Changing kinetics with osmolarity and the role of hyaluronan in pregnancy

The cervical remodeling process during pregnancy is characterized by progressive compositional and structural changes in the tissues extra-cellular matrix (ECM). Appropriately timed remodeling is critical for healthy gestation and prevention of premature cervical softening leading to preterm birth (PTB). Modification of the ECM glycosaminoglycans (GAGs) content with advancing pregnancy, especially the non-sulfated GAG hyaluronan (HA), is a fundamental change associated with cervical remodeling. While GAGs have numerous physiological roles, the mechanical consequence of evolving GAG content on cervical structure-function behavior remains an open question. Additionally, an understanding of cervical swelling properties, postulated to be regulated in part by GAGs, is required for the appropriate definition of a reference configuration for mechanical tests and to enhance biological understanding. To investigate cervical swelling, osmotic loading tests are conducted on isolated wild type mouse cervices throughout pregnancy. These tests are performed in various osmolarity solutions to assess the influence of the media on swelling kinetics. A genetically altered strain of mice with depletion of cervical HA is also tested to elucidate the contribution of HA to tissue swelling. Results show ex vivo cervical swelling is significant with volume changes ranging from 20 to 100% after 3h of free swelling. The swelling kinetics depend highly on osmolarity of the media and is altered with advancing pregnancy. The contribution of HA to swelling is only significant in hypo-osmotic solution when HA cervical content is high at the end of pregnancy. In summary, it is critical to account for swelling deformation mechanisms after excision in mechanical experiments. STATEMENT OF SIGNIFICANCE: The cervical extracellular matrix (ECM) undergoes drastic changes to fulfill the functional change of the cervix during pregnancy. Inappropriate timing for this transformation can result in preterm birth, a severe clinical challenge. One of the fundamental changes of the cervical ECM is the significant modification of the glycosaminoglycan content, especially hyaluronan (HA), which is thought to contribute significantly to the swelling and mechanical properties of the cervix. This study aims to measure the swelling kinetics of cervical tissue during pregnancy and to investigate the role of HA in these swelling tendencies. Results show the significant swelling of cervical tissue, which evolves as pregnancy progresses, highlighting a key material property feature of the remodeled cervix. Using a mouse strain with a cervical HA depletion, this work shows HA contributes to the swelling trends of late-term cervical tissue, in a hypo-osmotic solution.

Host inflammatory response is the major marker of severe respiratory syncytial virus infection in older adults

OBJECTIVES

We aim to study the viral kinetics and host inflammatory response of RSV infection in older adults, and their correlation with disease severity.

METHODS

We performed a prospective observational study in adults with RSV infection. We serially collected nasal-throat swabs for quantification of RSV-A and RSV-B viral load, and peripheral blood samples for measurement of cytokine/chemokine concentrations. The study endpoints were (i) requiring supplemental oxygen therapy, and (ii) non-invasive ventilation, intensive care, or died within 30 days of admission. We performed multivariable logistic regression models to identify independent variables for severe disease.

RESULTS

We enrolled 71 hospitalized patients and 10 outpatients treated for RSV infection (median age 75 years, 51% male, and 74% with comorbidities). Among hospitalized patients, 61% required supplemental oxygen therapy, and 18% had severe disease requiring non-invasive ventilation or intensive care, or died within 30 days. Inflammatory cytokine/chemokines IL-6, CXCL8/IL-8, CXCL9/MIG and CXCL10/IP-10 increased significantly during the acute phase of illness. IL-6 concentration was independently associated with severe disease after adjusting for confounding factors. RSV viral load was not associated with disease severity throughout the course of illness.

CONCLUSION

Host inflammatory response is a major marker of severe disease in older adults with RSV infection.

Pre-Vaccine Positivity of SARS-CoV-2 Antibodies in Alberta, Canada during the First Two Waves of the COVID-19 Pandemic

We systematically evaluated SARS-CoV-2 IgG positivity in a provincial cohort to understand the local epidemiology of COVID-19 and support evidence-based public health decisions. Residual blood samples were collected for serology testing over 5-day periods monthly from June 2020 to January 2021 from six clinical laboratories across the province of Alberta, Canada. A total of 93,993 individual patient samples were tested with a SARS-CoV-2 nucleocapsid antibody assay with positives confirmed using a spike antibody assay. Population-adjusted SARS-CoV-2 IgG seropositivity was 0.92% (95% confidence interval [CI]: 0.91 to 0.93%) shortly after the first COVID-19 wave in June 2020, increasing to 4.63% (95% CI: 4.61 to 4.65%) amid the second wave in January 2021. There was no significant difference in seropositivity between males and females (1.39% versus 1.27%; P = 0.11). Ages with highest seropositivity were 0 to 9 years (2.71%, 95% CI: 1.64 to 3.78%) followed by 20 to 29 years (1.58%, 95% CI: 1.12 to 2.04%), with the lowest rates seen in those aged 70 to 79 (0.79%, 95% CI: 0.65 to 0.93%) and >80 (0.78%, 95% CI: 0.60 to 0.97%). Compared to the seronegative group, seropositive patients inhabited geographic areas with lower household income ($87,500 versus $97,500; P < 0.001), larger household sizes, and higher proportions of people with education levels of secondary school or lower, as well as immigrants and visible minority groups (all P < 0.05). A total of 53.7% of seropositive individuals were potentially undetected cases with no prior positive COVID-19 nucleic acid test (NAAT). Antibodies were detectable in some patients up to 9 months post positive NAAT result. This seroprevalence study will continue to inform public health decisions by identifying at-risk demographics and geographical areas. IMPORTANCE Using SARS-CoV-2 serology testing, we assessed the proportion of people in Alberta, Canada (population 4.4 million) positive for COVID-19 antibodies, indicating previous infection, during the first two waves of the COVID-19 pandemic (prior to vaccination programs). Linking these results with sociodemographic population data provides valuable information as to which groups of the population are more likely to have been infected with the SARS-CoV-2 virus to help facilitate public health decision-making and interventions. We also compared seropositivity data with previous COVID-19 molecular testing results. Absence of antibody and molecular testing were highly correlated (95% negative concordance). Positive antibody correlation with a previous positive molecular test was low, suggesting the possibility of mild/asymptomatic infection or other reasons leading individuals from seeking medical attention. Our data highlight that the true estimate of population prevalence of COVID-19 is likely best informed by combining data from both serology and molecular testing.

MicroRNAs as biomarkers of atrophic scarring in acne: a cross-sectional analysis of 41 patients

BACKGROUND

Acne is the commonest inflammatory dermatosis seen worldwide. Atrophic acne scarring is a frequent complication, which can arise from acne of any severity. Micro (mi)RNAs are noncoding RNA molecules of 19-25 nucleotides that function as post-transcriptomic mediators of gene expression. They have demonstrated differential expression in various pathologies, such as eczema and psoriasis, allowing for a unique miRNA 'signature' profile to be established for different disease states.

AIM

To establish a miRNA signature for acne, and acne-associated atrophic scarring and to identify if a pattern of circulating miRNA is evident in patients who are prone to scarring.

METHODS

In total, 41 participants were consecutively recruited to this study. Circulating miRNA was quantified from plasma samples in all 41 patients, while in 8 patients, and in a further validation cohort of 9 patients, whole miRNAome was undertaken from tissue specimens, which included lesional, normal and where present, scarred skin.

RESULTS

Three miRNAs, miR-223, miR-21 and miR-150, were statistically significantly overexpressed in acne lesions, and notably, in clinically uninvolved skin in participants prone to scarring. In this subgroup, we also found statistically significantly elevated levels of circulating miRNA-21 and miRNA-150.

CONCLUSION

The presence of elevated levels of these specific miRNAs in the serum of patients with acne raises the potential of a blood test to identify those at risk of scarring, allowing for earlier intervention with effective therapy.

Burden of noninfluenza respiratory viral infections in adults admitted to hospital: analysis of a multiyear Canadian surveillance cohort from 2 centres

BACKGROUND:

Data on the outcomes of noninfluenza respiratory virus (NIRV) infections among hospitalized adults are lacking. We aimed to study the burden, severity and outcomes of NIRV infections in this population.

METHODS:

We analyzed pooled patient data from 2 hospital-based respiratory virus surveillance cohorts in 2 regions of Canada during 3 consecutive seasons (2015/16, 2016/17, 2017/18; n = 2119). We included patients aged ≥ 18 years who developed influenza-like illness or pneumonia and were hospitalized for management. We included patients confirmed positive for ≥ 1 virus by multiplex polymerase chain reaction assays (respiratory syncytial virus [RSV], human rhinovirus/enterovirus (hRV), human coronavirus (hCoV), metapneumovirus, parainfluenza virus, adenovirus, influenza viruses). We compared patient characteristics, clinical severity conventional outcomes (e.g., hospital length-of stay, 30-day mortality) and ordinal outcomes (5 levels: discharged, receiving convalescent care, acute ward or intensive care unit [ICU] care and death) for patients with NIRV infections and those with influenza.

RESULTS:

Among 2119 adults who were admitted to hospital, 1156 patients (54.6%) had NIRV infections (hRV 14.9%, RSV 12.9%, hCoV 8.2%) and 963 patients (45.4%) had influenza (n = 963). Patients with NIRVs were younger (mean 66.4 [standard deviation 20.4] yr), and more commonly had immunocompromising conditions (30.3%) and delay in diagnosis (median 4.0 [interquartile range (IQR) 2.0–7.0] days). Overall, 14.6% (12.4%–19.5%) of NIRV infections were acquired in hospital. Admission to ICU (18.2%, median 6.0 [IQR 3.0–13.0] d), hospital length-of-stay (median 5.0 [IQR 2.0–10.0] d) and 30-day mortality (8.4%; RSV 9.5%, hRV 6.6%, hCoV 9.2%) and the ordinal outcomes were similar for patients with NIRV infection and those with influenza. Age > 60 years, immunocompromised state and hospital-acquired viral infection were associated with worse outcomes. The estimated median cost per acute care admission was $6000 (IQR $2000–$16 000).

INTERPRETATION:

The burden of NIRV infection is substantial in adults admitted to hospital and associated outcomes may be as severe as for influenza, suggesting a need to prioritize therapeutics and vaccines for at-risk people.

Burden of influenza B virus infection and considerations for clinical management

Influenza B viruses cause significant morbidity and mortality, particularly in children, but the awareness of their impact is often less than influenza A viruses partly due to their lack of pandemic potential. Here, we summarise the biology, epidemiology and disease burden of influenza B, and review existing data on available antivirals for its management. There has long been uncertainty surrounding the clinical efficacy of neuraminidase inhibitors (NAIs) for influenza B treatment. In this article, we bring together the existing data on NAIs and discuss these alongside recent large randomised controlled trial data for the new polymerase inhibitor baloxavir in high-risk influenza B patients. Finally, we offer considerations for the clinical management of influenza B, with a focus on children and high-risk patients where disease burden is highest.

The change of serum serotonin levels between acute coronary syndrome and chronic stable angina undergoing percutaneous coronary intervention

Background

Activated platelets release serotonin (5-hydroxytryptamine, 5HT) causing vasoconstriction and aggregation of platelets in patients with acute coronary syndrome (ACS). It can lead to undergo percutaneous coronary intervention (PCI). We investigated the serial changes of serotonin level in patients with ACS and chronic stable angina (CSA) treated with PCI.

Methods

From July 2009 to April 2010, 123 consecutive patients who have undergone PCI for either ACS (n=63) or CSA (n=60) were enrolled. After the loading dose of aspirin 300mg and clopidogrel 600mg before PCI, maintenance once daily dose of 100mg and 75mg have been given from the day after PCI in all patients. Serum serotonin level (SERO) were serially measured at baseline, pre-, post-PCI, 90 min, 6 hours, 12 hours, 24 hours and 48 hours to compare between ACS and CSA groups. All demographic, biochemical variables, and clinical events were also collected for comparison in each group.

Results

SERO at post-PCI (55.2±120.0 vs 20.1±24.0, p=0.03) and peak level (94.0±170.9 vs 38.8±72.3, p=0.02) were significantly higher in ACS group. SERO after 90 min (34.4±66.1 vs 28.7±38.2, p=0.8), 6 hours (23.9±38.3 vs 10.1±10.0, p=0.34), 24 hours (55.8±108.5 vs 37.2±88.2, p=0.39) and 48 hours (43.5±122.9 vs 25.2±65.5, p=0.53) tended to be higher in ACS group than CSA group without statistical significance. SERO rebounded at 24 hours post-PCI and dropped at 48 hours.

Conclusions

SERO was more elevated in patients with ACS than those with CSA undergoing PCI, suggesting the need for more potent and sustained platelet inhibition particularly in ACS patients. SERO might be considered as a substitute marker of platelet activation. Triple antiplatelet therapy including selective serotonin receptor antagonist on top of aspirin and clopidogrel could be as an option for ACS patients undergoing PCI

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): Hallym University Research Fund 2017 (HURF-2017-84)

Comparison of prasugrel and ticagrelor for patient with acute coronary syndrome: a systematic review and meta-analysis

Background

Prasugrel and ticagrelor are both effective anti-platelet drugs for patients with acute coronary syndrome. However, there has been limited data on the direct comparison of prasugrel and ticagrelor until the recent ISAR-REACT 5 trial.

Purpose

To compare the efficacy of prasugrel and ticagrelor in patients with acute coronary syndrome with respect to the primary composite endpoint of myocardial infarction (MI), stroke or cardiac cardiovascular death, and secondary endpoints including MI, stroke, cardiovascular death, major bleeding (Bleeding Academic Research Consortium (BARC) type 2 or above), and stent thrombosis within 1 year.

Methods

Meta-analysis was performed on randomised controlled trials (RCT) up to December 2019 that randomised patients with acute coronary syndrome to either prasugrel or ticagrelor. RCTs were identified from Medline, Embase and ClinicalTrials.gov using Cochrane library CENTRAL by 2 independent reviewers with “prasugrel” and “ticagrelor” as search terms. Effect estimates with confidence intervals were generated using the random effects model by extracting outcome data from the RCTs to compare the primary and secondary clinical outcomes. Cochrane risk-of-bias tool for randomised trials (Ver 2.0) was used for assessment of all eligible RCTs.

Results

411 reports were screened, and we identified 11 eligible RCTs with 6098 patients randomised to prasugrel (n=3050) or ticagrelor (n=3048). The included trials had a follow up period ranging from 1 day to 1 year. 330 events on the prasugrel arm and 408 events on the ticagrelor arm were recorded. There were some concerns over the integrity of allocation concealment over 7 trials otherwise risk of other bias was minimal. Patients had a mean age of 61±4 (76% male; 50% with ST elevation MI; 35% with non-ST elevation MI; 15% with unstable angina; 25% with diabetes mellitus; 64% with hypertension; 51% with hyperlipidaemia; 42% smokers). There was no significant difference in risk between the prasugrel group and the ticagrelor group on the primary composite endpoint (Figure 1) (Risk Ratio (RR)=1.17; 95% CI=0.97–1.41; p=0.10, I2=0%). There was no significant difference between the use of prasugrel and ticagrelor with respect to MI (RR=1.24; 95% CI=0.81–1.90; p=0.31); stroke (RR=1.05; 95% CI=0.66–1.67; p=0.84); cardiovascular death (RR=1.01; 95% CI=0.75–1.36; p=0.95); BARC type 2 or above bleeding (RR=1.17; 95% CI =0.90–1.54; p=0.24); stent thrombosis (RR=1.58; 95% CI =0.90–2.76; p=0.11).

Conclusion

Compared with ticagrelor, prasugrel did not reduce the primary composite endpoint of MI, stroke and cardiovascular death within 1 year. There was also no significant difference in the risk of MI, stroke, cardiovascular death, major bleeding and stent thrombosis respectively.

Figure 1. Primary Objective

Funding Acknowledgement

Type of funding source: None

Baloxavir Marboxil for Prophylaxis against Influenza in Household Contacts

BACKGROUND

Baloxavir marboxil (baloxavir) is a polymerase acidic protein (PA) endonuclease inhibitor with clinical efficacy in the treatment of uncomplicated influenza, including in outpatients at increased risk for complications. The postexposure prophylactic efficacy of baloxavir in the household setting is unclear.

METHODS

We conducted a multicenter, double-blind, randomized, placebo-controlled trial to evaluate the postexposure prophylactic efficacy of baloxavir in household contacts of index patients with confirmed influenza during the 2018-2019 season in Japan. The participants were assigned in a 1:1 ratio to receive either a single dose of baloxavir or placebo. The primary end point was clinical influenza, as confirmed by reverse-transcriptase-polymerase-chain-reaction testing, over a period of 10 days. The occurrence of baloxavir-selected PA substitutions associated with reduced susceptibility was assessed.

RESULTS

A total of 752 household contacts of 545 index patients were randomly assigned to receive baloxavir or placebo. Among the index patients, 95.6% had influenza A virus infection, 73.6% were younger than 12 years of age, and 52.7% received baloxavir. Among the participants who could be evaluated (374 in the baloxavir group and 375 in the placebo group), the percentage in whom clinical influenza developed was significantly lower in the baloxavir group than in the placebo group (1.9% vs. 13.6%) (adjusted risk ratio, 0.14; 95% confidence interval [CI], 0.06 to 0.30; P<0.001). Baloxavir was effective in high-risk, pediatric, and unvaccinated subgroups of participants. The risk of influenza infection, regardless of symptoms, was lower with baloxavir than with placebo (adjusted risk ratio, 0.43; 95% CI, 0.32 to 0.58). The incidence of adverse events was similar in the two groups (22.2% in the baloxavir group and 20.5% in the placebo group). In the baloxavir group, the viral PA substitutions I38T/M or E23K were detected in 10 (2.7%) and 5 (1.3%) participants, respectively. No transmission of these variants from baloxavir-treated index patients to participants in the placebo group was detected; however, several instances of transmission to participants in the baloxavir group could not be ruled out.

CONCLUSIONS

Single-dose baloxavir showed significant postexposure prophylactic efficacy in preventing influenza in household contacts of patients with influenza. (Funded by Shionogi; Japan Primary Registries Network number, JapicCTI-184180.).

Effects of comorbidities on quality of life in Filipino people with tuberculosis

BACKGROUND: We investigated health-related quality of life (HrQoL) in Filipino people undergoing TB treatment, and whether HrQoL was negatively impacted by comorbidity with undernutrition, diabetes (DM) and anaemia.METHODS: Adult participants were enrolled in public facilities in Metro Manila (three sites) and Negros Occidental (two sites). Multivariate linear regression was used to model the four correlated domain scores from a WHOQOL-BREF questionnaire (physical, psychological, social, environmental). A forward-stepwise approach was used to select a final multivariable model with inclusion based on global tests of significance at P < 0.1.RESULTS: In 446 people on drug-susceptible TB treatment, DM and moderate/severe anaemia were not associated with HrQoL. After adjustment for age, sex, education, food insecurity, treatment adherence, inflammation, Category I or II TB treatment, treatment phase, current side effects and inhibited ability to work, moderate/severe undernutrition (body mass index < 17 kg/m²) was associated with lower HrQoL (P = 0.003) with reduced psychological (coefficient: -1.02, 95% CI -1.54 to -0.51), physical (-0.62, 95% CI -1.14 to -0.09) and environmental domain scores (-0.45, 95% CI -0.88 to -0.01). In 225 patients with known HIV status in Metro Manila, HIV was associated with modestly reduced HrQoL (P = 0.014).CONCLUSION: Nutritional status and food insecurity represent modifiable risk factors for poor HrQoL that may be alleviated through interventions.

Development of an Ordinal Scale Treatment Endpoint for Adults Hospitalized With Influenza

BACKGROUND

An obstacle in influenza therapeutics development is the lack of clinical endpoints, especially in hospitalized patients. A single time-point binary outcome measure is limited by patients' diverse clinical trajectories and low event rates.

METHODS

A 6-point ordinal scale with ascending clinical status severity (scoring: discharged; subacute care; acute care without/with respiratory failure; intensive care unit [ICU]; death) was proposed to study outcomes of adults hospitalized with influenza. Individual patient data from 2 active surveillance cohorts' datasets (2015/2016-2017/2018; Edmonton, Hong Kong) was used for evaluation. The impact of neuraminidase inhibitor (NAI) treatment on longitudinal ordinal outcome changes over 30 days was analyzed using mixed-effects ordinal logistic regression and group-based trajectory models.

RESULTS

Patient (n = 1226) baseline characteristics included age (mean 68.0 years), virus-type (A 78.1%, B 21.9%), respiratory failure (57.2%), ICU admittance (14.4%), and NAI treatment within 5 days of illness (69.2%). Outcomes at 30 days included discharged (75.2%), subacute care (13.7%), acute care (4.5%), and death (6.6%). Two main clinical trajectories were identified, predictive by baseline scoring (mean ± SD, 4.3 ± 0.6 vs 3.5 ± 0.6, P < .001). Improved outcomes with NAI treatment within 5 days were indicated by significantly lower clinical status scores over time (unadjusted odds ratio [OR], 0.53; 95% confidence interval [CI], .41-.69; P < .001; adjusted OR, 0.62; 95% CI, .50-.77; P < .001, for baseline score, age, and within-patient correlations). In subanalysis, influenza vaccination was also associated with lower scores (adjusted OR, 0.67; 95% CI, .50-.90; P = .007). Analyses of binary endpoints showed insignificant results.

CONCLUSIONS

The ordinal outcome scale is a potentially useful clinical endpoint for influenza therapeutic trials, which could account for the diverse clinical trajectories of hospitalized patients, warranting further development.

First hospitalized case of laboratory-confirmed coronavirus disease 2019 (COVID-19) in Alberta, Canada

As the pandemic of coronavirus disease 2019 (COVID-19) continues to evolve globally and within our Canadian borders, hospitals will begin to see an increasing number of confirmed or suspected cases at their doors. Although many patients can be managed at home, a reasonable proportion will experience progression of disease requiring hospitalization and potentially mechanical ventilation and intensive care. Herein, we report the presentation of the first case of COVID-19 admitted to hospital in Alberta. While The patient's course was mild, this case highlights a number of key points-namely the importance of widespread testing in the community to help inform emergency services (ambulance) workers and receiving front-line health care staff. Other important points include in-hospital monitoring and pharmacologic treatment.

Delayed Diagnosis of Respiratory Syncytial Virus Infections in Hospitalized Adults: Individual Patient Data, Record Review Analysis and Physician Survey in the United States

BACKGROUND

Despite the prevalence of respiratory syncytial virus (RSV) in adults hospitalized with acute respiratory infections, guidelines for the diagnosis and management of RSV have not been established. This analysis evaluated the role and timeliness of RSV diagnostic testing and its potential impact on clinical outcomes.

METHODS

We analyzed individual patient data from hospitalized adults with confirmed RSV infections during 2 North American RSV seasons. Participating physicians reported clinical, virologic diagnosis, and outcome variables using a standardized online case form.

RESULTS

Across 32 US states, 132 physicians reported 379 RSV cases. Polymerase chain reaction-based diagnostics were the most common type of test ordered (94.2%) with <5% ordered specifically to diagnose RSV. Most tests (67.6%) were ordered in hospital wards or intensive care units. Overall, 47.4%, 30.9%, and 21.7% of patients had RSV diagnosed <12, 12‒24, and >24 hours after hospital admission, respectively. Later diagnosis was associated with longer hospital stays (n = 145; R = +0.191; P < .05) and greater antibiotic use.

CONCLUSION

Diagnosis of RSV infection in hospitalized adults is often delayed, which may affect clinical management and outcomes. Our findings indicate the need to improve the diagnostic strategies in this patient population.

Adherence to Treatment Guideline Improves Patient Outcomes in a Prospective Cohort of Adults Hospitalized for Community-Acquired Pneumonia

Background

Understanding local epidemiology and etiologies of community-acquired pneumonia in hospitalized patients is crucial for determining the appropriateness of treatment guidelines. We aim to determine the etiologies, severity, and outcomes in adults hospitalized for community-acquired pneumonia and to study the impact of empirical antibiotic therapy on patient outcomes.

Methods

We performed a prospective observational cohort study involving adults hospitalized for community-acquired pneumonia in Hong Kong. Sputum, nasopharyngeal aspirate, blood, and urine were collected for bacterial culture, molecular tests for detection of viruses and atypical pathogens, and antigen tests. Multivariable logistic regression model and Cox proportional hazard models were performed to determine independent factors associated with prolonged hospitalization and mortality.

Results

From February 2017 to July 2018, 258 patients were enrolled. The median age was 73 (interquartile range, 61-80) years, 66% were male, 57% had underlying chronic illnesses, 13% had CURB-65 score ≥3, and 10% had higher 1-year mortality. Pathogens were identified in 45% of patients; 20% had viral, 15% had bacterial, and 9% had polymicrobial pneumonia. Streptococcus pneumoniae (12%), influenza virus (12%), and Mycoplasma pneumoniae (1.2%) were the most common bacterial, viral, and atypical pathogens, respectively. Nonadherence to local empirical antibiotic treatment guidelines (primarily recommending beta-lactam and doxycycline) was observed in 25% and was independently associated with prolonged hospitalization (≥7 days) and higher mortality, after adjustment for age, underlying chronic illness, and disease severity.

Conclusions

Adherence to treatment guidelines was associated with shorter hospitalization and improved survival. We provided evidence for the use of doxycycline for coverage of atypical pathogens in nonsevere pneumonia.