Neuraminidase inhibitors, superinfection and corticosteroids affect survival of influenza patients

Inhibition of cap-dependent endonuclease in influenza virus with ADC189: a pre-clinical analysis and phase I trial

ADC189 is a novel drug of cap-dependent endonuclease inhibitor. In our study, its antiviral efficacy was evaluated in vitro and in vivo, and compared with baloxavir marboxil and oseltamivir. A first-in-human phase I study in healthy volunteers included single ascending dose (SAD) and food effect (FE) parts. In the preclinical study, ADC189 showed potent antiviral activity against various types of influenza viruses, including H1N1, H3N2, influenza B virus, and highly pathogenic avian influenza, comparable to baloxavir marboxil. Additionally, ADC189 exhibited much better antiviral efficacy than oseltamivir in H1N1 infected mice. In the phase I study, ADC189 was rapidly metabolized to ADC189-I07, and its exposure increased proportionally with the dose. The terminal elimination half-life (T1/2) ranged from 76.69 to 98.28 hours. Of note, food had no effect on the concentration, clearance, and exposure of ADC189. It was well tolerated, with few treatment-emergent adverse events (TEAEs) reported and no serious adverse events (SAEs). ADC189 demonstrated excellent antiviral efficacy both in vitro and in vivo. It was safe, well-tolerated, and had favorable pharmacokinetic characteristics in healthy volunteers, supporting its potential for single oral dosing in clinical practice.

Influenza presentations and use of neuraminidase inhibitors by Australian general practice registrars: a cross-sectional analysis from the ReCEnT study

OBJECTIVE

This study aims to establish prevalence and associations of (1) influenza and influenza-like illness (IILI) presentations to Australian general practice (GP) registrars (trainees) and (2) the use of neuraminidase inhibitors (NAIs) by GP registrars for new presentations of IILI, for the 10 years leading up to the COVID-19 pandemic in Australia (2010-2019).

DESIGN

This was a cross-sectional analysis of the Registrar Clinical Encounters in Training ongoing inception cohort study of the in-consultation experience and clinical behaviours of GP registrars. Data are collected by individual registrars three times (from 60 consecutive consultations each time) at 6 monthly intervals. Data include diagnoses/problems managed and medicines prescribed, along with multiple other variables. Univariate and multivariable logistic regression was used to establish associations of registrars seeing patients with IILI and of prescribing NAIs for IILI.

SETTING

Teaching practices within the Australian general practitioner specialist vocational training programme. Practices were located in five of the six Australian states (plus one territory).

PARTICIPANTS

GP registrars in each of their three compulsory 6-month GP training terms.

RESULTS

From 2010 to 2019, 0.2% of diagnoses/problems seen by registrars were IILI. 15.4% of new IILI presentations were prescribed an NAI. IILI diagnoses were less likely in younger (0-14) and older (65+) age groups, and more likely in an area of higher socioeconomic advantage. There was considerable variation in NAI prescribing between regions. There was no significant association of prescribing NAIs with age or Aboriginal and/or Torres Strait Islander patients.

CONCLUSIONS

IILI presentations were more likely among working-age adults and not among those groups at higher risk. Similarly, high-risk patient groups who would benefit most were not more likely to receive NAIs. The epidemiology and management of IILI has been distorted by the COVID-19 pandemic, but the burden of influenza in vulnerable populations must not be overlooked. Appropriately targeted antiviral therapy with NAIs influences outcomes for vulnerable patients. General practitioners manage the majority of IILI in Australia, and understanding GP IILI presentation and NAI prescribing patterns is a key first step to enabling sound and rational prescribing decisions for better patient outcomes.

Managing the Next Wave of Influenza and/or SARS-CoV-2 in the ICU—Practical Recommendations from an Expert Group for CAPA/IAPA Patients

The aim of this study was to establish practical recommendations for the diagnosis and treatment of influenza-associated invasive aspergillosis (IAPA) based on the available evidence and experience acquired in the management of patients with COVID-19-associated pulmonary aspergillosis (CAPA). The CAPA/IAPA expert group defined 14 areas in which recommendations would be made. To search for evidence, the PICO strategy was used for both CAPA and IAPA in PubMed, using MeSH terms in combination with free text. Based on the results, each expert developed recommendations for two to three areas that they presented to the rest of the group in various meetings in order to reach consensus. As results, the practical recommendations for the management of CAPA/IAPA patients have been grouped into 12 sections. These recommendations are presented for both entities in the following situations: when to suspect fungal infection; what diagnostic methods are useful to diagnose these two entities; what treatment is recommended; what to do in case of resistance; drug interactions or determination of antifungal levels; how to monitor treatment effectiveness; what action to take in the event of treatment failure; the implications of concomitant corticosteroid administration; indications for the combined use of antifungals; when to withdraw treatment; what to do in case of positive cultures for Aspergillus spp. in a patient with severe viral pneumonia or Aspergillus colonization; and how to position antifungal prophylaxis in these patients. Available evidence to support the practical management of CAPA/IAPA patients is very scarce. Accumulated experience acquired in the management of CAPA patients can be very useful for the management of IAPA patients. The expert group presents eminently practical recommendations for the management of CAPA/IAPA patients.

The The use of corticosteroid therapy for COVID-19 patients: an evidence-based overview

Since the World Health Organization declared COVID-19 as a pandemic, huge efforts to promote better treatment for the patients raised from the scientific community. One of the most effective treatment is the administration of corticosteroid in specific stages of the disease, once that severe COVID-19 pathophysiology evolves an exuberant inflammatory response, resulting in uncontrolled pulmonary inflammation and multisystem damage. However, it is still discussed whether some drugs, such as dexamethasone, are more effective than others, such as hydrocortisone and methylprednisolone. Therefore, we constructed here a comprehensive overview, based on clinical studies with detailed methodological procedures, regarding the role of corticosteroids in COVID-19 treatment. We aimed to address how the current evidence support their use in this scenario.

Association between Glucocorticoids and Mortality in Patients with Severe Pneumonia: A Systematic Review and Meta-Analysis Based on Randomized Controlled Trials

Objective

To explore the associations between glucocorticoid use and the clinical outcome of patients with severe pneumonia.

Methods

Medical databases including PubMed, EMBASE, and ScienceDirect were searched for relevant literature. Two independent researchers extracted the primary endpoint from the included literature. The Cochrane Q test and I² statistics were used to evaluate the interstudy heterogeneity. The combined risk estimates were calculated by random effect model, and the source of heterogeneity was evaluated by subgroup analysis. Funnel plot and Egger's test were used to assess publication bias. P < 0.05 denoted statistical significance.

Results

A total of 12 literature, including 8171 patients with 1083 deaths, were included in this study for meta-analysis. The use of glucocorticoids significantly increased the mortality (RR = 1.44, 95% CI: 1.13, 1.84, P < 0.001), the risk of requiring mechanical ventilation (RR = 1.62, 95% CI: 1.30, 2.02, P < 0.001), and the incidence of nosocomial infection (RR = 1.36, 95% CI: 1.01, 1.82, P = 0.04) in patients with severe pneumonia as compared with the control group. In addition, the use of glucocorticoids did not seem to be associated with length of treatment in the intensive care unit (mean difference = 1.47, 95% CI: -1.04, 3.96, P = 0.25) and the length of hospital stay (mean difference = 0.55, 95% CI: -3.90, 4.99, P = 0.81).

Conclusion

The use of glucocorticoids may increase the mortality, the incidence of hospital-acquired pneumonia, and the need for mechanical ventilation in patients with severe pneumonia.

Respiratory syncytial virus-associated acute respiratory illness in adult non-immunocompromised patients: Outcomes, determinants of outcomes, and the effect of oral ribavirin treatment

Background

Respiratory syncytial virus (RSV) is an increasingly common cause of respiratory illness in adult non‐immunocompromised patients. Oral ribavirin was reported to improve outcomes of RSV infection in immunocompromised patients. This study aimed to determine the outcomes of non‐immunocompromised patients hospitalized with RSV‐associated acute respiratory illnesses (RSV‐ARI), the factors independently associated with the outcomes and the effect of oral ribavirin treatment.

Methods

This retrospective, observational cohort study included 175 adults admitted to the hospital with virologically confirmed RSV‐ARI during 2014–2019. Severe ARI was identified using Infectious Diseases Society of America/American Thoracic Society (IDSA/ATS) criteria for severe community‐acquired pneumonia. The primary outcome was all‐cause mortality within 30 days after enrollment. A multivariable Cox model was performed to identify significant predictors of mortality.

Results

Mean age was 76 ± 12.7 years. Seventy‐eight (44.6%) patients met the diagnostic criteria for severe ARI. Thirty‐six (20.6%) patients required invasive mechanical ventilation, and 11 (6.3%) required vasopressor. Ninety‐nine (56.6%) patients received oral ribavirin treatment, and 52 (29.7%) received systemic corticosteroids. Forty‐one (23.4%) patients had evidence of bacterial infection. Overall mortality was 7.4%. Mortality among patients with non‐severe ARI and severe ARI was 1.04% and 15.4%, respectively. Estimated glomerular filtration rate <50 ml/min/1.73 m², severe ARI, systemic corticosteroids, and bacterial infection were independently associated with higher risk of mortality. Treatment with oral ribavirin was the only factor associated with reduced mortality (adjusted HR: 0.19, 95% CI: 0.04–0.9, P = 0.03).

Conclusion

RSV‐ARI may result in significant mortality and health care utilization. Treatment with oral ribavirin may improve survival in these patients.

The effect of statins on the prevalence and mortality of influenza virus infection: a systematic review and meta-analysis

INTRODUCTION

Influenza virus infection is associated with high morbidity and mortality, and so additional therapeutic strategies to reduce the burden for healthcare systems are needed. Statins, by virtue of their anti-inflammatory and immunomodulatory effects, have been hypothesized as capable of influencing the host's response against the influenza virus. The aim of this meta-analysis was to assess the effect of ongoing statin treatment on susceptibility to influenza virus infection and on influenza-associated mortality.

MATERIAL AND METHODS

Studies investigating the impact of statin treatment on influenza prevalence and mortality were searched for in the PubMed-Medline, Scopus, ISI Web of Knowledge, Embase, Proquest, OVID, EBSCO, and CINAHL databases (up to 8 November 2021). Fixed- and random-effects models and the generic inverse variance method were used for quantitative data synthesis.

RESULTS

In the meta-analysis of 14 arms of 2 eligible studies, including 14,997 flu-vaccinated and unvaccinated patients, treatment with statins was associated with a reduction of influenza virus prevalence (odds ratio (OR) = 0.85, 95% confidence interval (CI): 0.73-0.99; p = 0.040). No significant effect of statins on the susceptibility to influenza infection was observed in the distinct communities of either vaccinated or unvaccinated subjects. Among 9 arms of 6 eligible studies, including 87,204 patients, the use of statins among patients with influenza was associated with a reduced mortality (OR = 0.68, 95% CI: 0.56, 0.82; p < 0.001). This result was confirmed for both 30-day mortality since influenza infection diagnosis (OR = 0.61, 95% CI: 0.47, 0.80; p <0.001) and for up to 90-day mortality (OR = 0.74, 95% CI: 0.55, 1.00; p = 0.042).

CONCLUSIONS

Reduced influenza prevalence and increased survival from influenza infection was observed in patients on ongoing statin treatment. Further research is needed to define the possible role of statins as adjunctive therapy in patients with influenza infection.

Hyperinflammatory environment drives dysfunctional myeloid cell effector response to bacterial challenge in COVID-19

COVID-19 displays diverse disease severities and symptoms including acute systemic inflammation and hypercytokinemia, with subsequent dysregulation of immune cells. Bacterial superinfections in COVID-19 can further complicate the disease course and are associated with increased mortality. However, there is limited understanding of how SARS-CoV-2 pathogenesis and hypercytokinemia impede the innate immune function against bacterial superinfections. We assessed the influence of COVID-19 plasma hypercytokinemia on the functional responses of myeloid immune cells upon bacterial challenges from acute-phase COVID-19 patients and their corresponding recovery-phase. We show that a severe hypercytokinemia status in COVID-19 patients correlates with the development of bacterial superinfections. Neutrophils and monocytes derived from COVID-19 patients in their acute-phase showed an impaired intracellular microbicidal capacity upon bacterial challenges. The impaired microbicidal capacity was reflected by abrogated MPO and reduced NETs production in neutrophils along with reduced ROS production in both neutrophils and monocytes. Moreover, we observed a distinct pattern of cell surface receptor expression on both neutrophils and monocytes, in line with suppressed autocrine and paracrine cytokine signaling. This phenotype was characterized by a high expression of CD66b, CXCR4 and low expression of CXCR1, CXCR2 and CD15 in neutrophils and low expression of HLA-DR, CD86 and high expression of CD163 and CD11b in monocytes. Furthermore, the impaired antibacterial effector function was mediated by synergistic effect of the cytokines TNF-α, IFN-γ and IL-4. COVID-19 patients receiving dexamethasone showed a significant reduction of overall inflammatory markers in the plasma as well as exhibited an enhanced immune response towards bacterial challenge ex vivo. Finally, broad anti-inflammatory treatment was associated with a reduction in CRP, IL-6 levels as well as length of ICU stay and ventilation-days in critically ill COVID-19 patients. Our data provides insights into the transient functional dysregulation of myeloid immune cells against subsequent bacterial infections in COVID-19 patients and describe a beneficial role for the use of dexamethasone in these patients.

Management of Severe Influenza

Influenza infection causes severe illness in 3 to 5 million people annually, with up to an estimated 650,000 deaths per annum. As such, it represents an ongoing burden to health care systems and human health. Severe acute respiratory infection can occur, resulting in respiratory failure requiring intensive care support. Herein we discuss diagnostic approaches, including development of CLIA-waived point of care tests that allow rapid diagnosis and treatment of influenza. Bacterial and fungal coinfections in severe influenza pneumonia are associated with worse outcomes, and we summarize the approach and treatment options for diagnosis and treatment of bacterial and Aspergillus coinfection. We discuss the available drug options for the treatment of severe influenza, and treatments which are no longer supported by the evidence base. Finally, we describe the supportive management and ventilatory approach to patients with respiratory failure as a result of severe influenza in the intensive care unit.

Evaluation of the therapeutic regimen in COVID-19 in transplant patients: where do immunomodulatory and antivirals stand?

BACKGROUND

The management of COVID-19 in organ transplant recipients is among the most imperative, yet less discussed, issues based on their immunocompromised status along with their vast post-transplant medication regimens. No conclusive study has been published to evaluate proper anti-viral and immunomodulator medications effect in treating COVID-19 patients to this date.

METHOD

This retrospective study was conducted in Shiraz Transplant Hospital, Iran from March 2020 to May 2021 and included COVID-19 diagnosed patients based on SARS-CoV-2 RT-PCR positive test who had been hospitalized for at least 48 h before enrolling in the study. Clinical and demographic information of patients, along with their treatment course and the medication used were evaluated and analyzed using multiple regression analysis.

RESULTS

A total of 245 patients with a mean age of 49.59 years were included with a mortality rate of 8.16%. The administration of Remdesivir as an anti-viral drug (P value < 0.001) and Tocilizumab as an immunomodulator drug (P value < 0.001) could reduce the hospitalization period in the hospital and the intensive care unit, as well as the mortality rates significantly. Meanwhile, the patients treated with Lopinavir/Ritonavir experienced a lower chance of survival (OR < 1, P value = 0.04). No significant difference was observed between various therapeutic regimens in clinical complications such as bacterial coinfections, cardiovascular and gastrointestinal adverse reactions, and liver or kidney dysfunctions.

CONCLUSION

The administration of Remdesivir as an anti-viral and Tocilizumab as an immunomodulatory drug in solid-organ transplant recipients could be promising treatments of choice to manage COVID-19.

COVID-19-related mortality in kidney transplant and haemodialysis patients: a comparative, prospective registry-based study

BACKGROUND

Coronavirus disease 2019 (COVID-19) has exposed haemodialysis (HD) patients and kidney transplant (KT) recipients to an unprecedented life-threatening infectious disease, raising concerns about kidney replacement therapy (KRT) strategy during the pandemic. This study investigated the association of the type of KRT with COVID-19 severity, adjusting for differences in individual characteristics.

METHODS

Data on KT recipients and HD patients diagnosed with COVID-19 between 1 February 2020 and 1 December 2020 were retrieved from the European Renal Association COVID-19 Database. Cox regression models adjusted for age, sex, frailty and comorbidities were used to estimate hazard ratios (HRs) for 28-day mortality risk in all patients and in the subsets that were tested because of symptoms.

RESULTS

A total of 1670 patients (496 functional KT and 1174 HD) were included; 16.9% of KT and 23.9% of HD patients died within 28 days of presentation. The unadjusted 28-day mortality risk was 33% lower in KT recipients compared with HD patients {HR 0.67 [95% confidence interval (CI) 0.52-0.85]}. In a fully adjusted model, the risk was 78% higher in KT recipients [HR 1.78 (95% CI 1.22-2.61)] compared with HD patients. This association was similar in patients tested because of symptoms [fully adjusted model HR 2.00 (95% CI 1.31-3.06)]. This risk was dramatically increased during the first post-transplant year. Results were similar for other endpoints (e.g. hospitalization, intensive care unit admission and mortality >28 days) and across subgroups.

CONCLUSIONS

KT recipients had a greater risk of a more severe course of COVID-19 compared with HD patients, therefore they require specific infection mitigation strategies.

A comprehensive review of COVID-19 biology, diagnostics, therapeutics, and disease impacting the central nervous system

The ongoing COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a highly transmissible disease. SARS-CoV-2 is estimated to have infected over 153 million people and to have caused over 3.2 million global deaths since its emergence in December 2019. SARS-CoV-2 is the seventh coronavirus known to infect humans, and like other coronaviruses, SARS-CoV-2 infection is characterized by a variety of symptoms including general flu-like symptoms such as a fever, sore throat, fatigue, and shortness of breath. Severe cases often display signs of pneumonia, lymphopenia, acute kidney injury, cardiac injury, cytokine storms, lung damage, acute respiratory distress syndrome (ARDS), multiple organ failure, sepsis, and death. There is evidence that around 30% of COVID-19 cases have central nervous system (CNS) or peripheral nervous system (PNS) symptoms along with or in the absence of the previously mentioned symptoms. In cases of CNS/PNS impairments, patients display dizziness, ataxia, seizure, nerve pain, and loss of taste and/or smell. This review highlights the neurological implications of SARS-CoV-2 and provides a comprehensive summary of the research done on SARS-CoV-2 pathology, diagnosis, therapeutics, and vaccines up to May 5.

The role of influenza A virus-induced hypercytokinemia

Influenza viruses are one of the leading causes of respiratory tract infections in humans and their newly emerging and re-emerging virus strains are responsible for seasonal epidemics and occasional pandemics, leading to a serious threat to global public health systems. The poor clinical outcome and pathogenesis during influenza virus infection in humans and animal models are often associated with elevated proinflammatory cytokines and chemokines production, which is also known as hypercytokinemia or "cytokine storm", that precedes acute respiratory distress syndrome (ARDS) and often leads to death. Although we still do not fully understand the complex nature of cytokine storms, the use of immunomodulatory drugs is a promising approach for treating hypercytokinemia induced by an acute viral infection, including highly pathogenic avian influenza virus infection and Coronavirus Disease 2019 (COVID-19). This review aims to discuss the immune responses and cytokine storm pathology induced by influenza virus infection and also summarize alternative experimental strategies for treating hypercytokinemia caused by influenza virus.

[Management of Adult Community-Acquired Pneumonia and Prevention - Update 2021 - Guideline of the German Respiratory Society (DGP), the Paul-Ehrlich-Society for Chemotherapy (PEG), the German Society for Infectious Diseases (DGI), the German Society of Medical Intensive Care and Emergency Medicine (DGIIN), the German Viological Society (DGV), the Competence Network CAPNETZ, the German College of General Practitioneers and Family Physicians (DEGAM), the German Society for Geriatric Medicine (DGG), the German Palliative Society (DGP), the Austrian Society of Pneumology Society (ÖGP), the Austrian Society for Infectious and Tropical Diseases (ÖGIT), the Swiss Respiratory Society (SGP) and the Swiss Society for Infectious Diseases Society (SSI)]

The present guideline provides a new and updated concept of the management of adult patients with community-acquired pneumonia. It replaces the previous guideline dating from 2016.The guideline was worked out and agreed on following the standards of methodology of a S3-guideline. This includes a systematic literature search and grading, a structured discussion of recommendations supported by the literature as well as the declaration and assessment of potential conflicts of interests.The guideline has a focus on specific clinical circumstances, an update on severity assessment, and includes recommendations for an individualized selection of antimicrobial treatment.The recommendations aim at the same time at a structured assessment of risk for adverse outcome as well as an early determination of treatment goals in order to reduce mortality in patients with curative treatment goal and to provide palliation for patients with treatment restrictions.

Clinical and etiological analysis of co-infections and secondary infections in COVID-19 patients: An observational study

Background

Co‐infections, secondary bacterial or fungal infections, are important risk factors for poor outcomes in viral infections. The prevalence of co‐infection and secondary infection in patients infected with SARS‐CoV‐2 is not well understood.

Aims

To investigate the role of co‐infections and secondary infections in disease severity of hospitalized individuals with COVID‐19.

Materials and Methods

A retrospective study was carried out between 11 January 2020 and 1 March 2020 among 408 laboratory confirmed COVID‐19 patients in China. These patients were divided into three groups based on disease severity: mild or moderate, severe, or critically ill. Microbiological pathogens in blood, urine, and respiratory tract specimens were detected by the combination of culture, serology, polymerase chain reaction, and metagenomic next‐generation sequencing (mNGS).

Results

The median age of participants was 48 years (IQR 34–60 years). Fifty‐two patients (12.7%) had at least one additional pathogen, 8.1% were co‐infected, and 5.1% had a secondary infection. There were 13 Mycoplasma pneumoniae cases, 8 Haemophilus influenzae cases, 8 respiratory viruses, and 3 Streptococcus pneumoniae cases, primarily detected in mild and moderate COVID‐19 patients. Hospital‐acquired infection pathogens were more common in critically ill patients. Compared to those without additional pathogens, patients with co‐infections and/or secondary infections were more likely to receive antibiotics (p < 0.001) and have elevated levels of d‐dimer (p = 0.0012), interleukin‐6 (p = 0.0027), and procalcitonin (p = 0.0002). The performance of conventional culture was comparable with that of mNGS in diagnosis of secondary infections.

Conclusion

Co‐infections and secondary infections existed in hospitalized COVID‐19 patients and were relevant to the disease severity. Screening of common respiratory pathogens and hospital infection control should be strengthened.

When should we use corticosteroids in severe community-acquired pneumonia?

PURPOSE OF REVIEW

This review aims to evaluate the evidence and recommendations for the prescription of corticosteroids as adjunctive therapy in patients with severe community-acquired pneumonia.

RECENT FINDINGS

Corticosteroids have been prescribed with the objective to attenuate the marked and persistent activation of the immune system. However, some causes of community-acquired pneumonia, namely viral, are associated with unexpected low levels of cytokines and depressed cellular immunity. As a result, several recent randomized controlled trials and large prospective observational studies repeatedly showed that corticosteroids had no impact on survival, and in some types of pneumonia like influenza, its use was associated with potential harmful effects like invasive aspergillosis. Apart from this, adverse effects, namely hyperglycemia, superinfections and increased length-of-stay, were frequent findings in the corticosteroid-treated patients.

SUMMARY

According to the current evidence, corticosteroids are recommended in Pneumocystis jiroveci pneumonia in HIV-infected patients and recommendations are against its use in influenza. In all other forms of severe community-acquired pneumonia, with the exclusion of SARS-CoV-2 pneumonia, the strength of the evidence does not support the safe and widespread use of corticosteroids as adjunctive therapy. Further studies are needed to identify subgroups of severe community-acquired pneumonia that can benefit or not from corticosteroids.

Early oseltamivir treatment improves survival in critically ill patients with influenza pneumonia

Background

The relationship between early oseltamivir treatment (within 48 h of symptom onset) and mortality in patients admitted to intensive care units (ICUs) with severe influenza is disputed. This study aimed to investigate the association between early oseltamivir treatment and ICU mortality in critically ill patients with influenza pneumonia.

Methods

This was an observational study of patients with influenza pneumonia admitted to 184 ICUs in Spain during 2009-2018. The primary outcome was to evaluate the association between early oseltamivir treatment and ICU mortality compared with later treatment. Secondary outcomes were to compare the duration of mechanical ventilation and ICU length of stay between the early and later oseltamivir treatment groups. To reduce biases related to observational studies, propensity score matching and a competing risk analysis were performed.

Results

During the study period, 2124 patients met the inclusion criteria. All patients had influenza pneumonia and received oseltamivir before ICU admission. Of these, 529 (24.9%) received early oseltamivir treatment. In the multivariate analysis, early treatment was associated with reduced ICU mortality (OR 0.69, 95% CI 0.51-0.95). After propensity score matching, early oseltamivir treatment was associated with improved survival rates in the Cox regression (hazard ratio 0.77, 95% CI 0.61-0.99) and competing risk (subdistribution hazard ratio 0.67, 95% CI 0.53-0.85) analyses. The ICU length of stay and duration of mechanical ventilation were shorter in patients receiving early treatment.

Conclusions

Early oseltamivir treatment is associated with improved survival rates in critically ill patients with influenza pneumonia, and may decrease ICU length of stay and mechanical ventilation duration.

Influenza management with new therapies

PURPOSE OF REVIEW

Influenza represents a significant treatment burden to critical care services. A variety of treatment strategies exist, with more and more therapeutic avenues opening up as research progresses. We examined both pharmacological and supportive treatment strategies currently available to see how they might be applied in an ICU setting.

RECENT FINDINGS

Supportive care in Influenza centres around optimizing respiratory failure, particularly through well established and recognized ventilatory strategies. Noninvasive ventilation and high-flow nasal oxygen may have a limited role in selected patients under carefully monitored circumstances. Drug therapy exerts only a modest clinical effect and has been poorly studied in the critically ill, though there is some evidence to support the use of neuraminidase inhibitors (NAI) - particularly oseltamivir - as early as possible in this cohort. Newer agents have failed to demonstrate superiority over NAIs but may be useful options if the patient fails to respond or should resistant influenza strains emerge. Steroid therapy, in the absence of another indication, must be recommended against given the repeated trend towards increased mortality in this group.

SUMMARY

Influenza management is an evolving field of significant interest to any critical care provider. Currently, good respiratory supportive care and early enteral oseltamivir are the best supported treatment strategies. Further study in the intensive care setting will be needed before the use of novel agents can be recommended.

Corticosteroids Treatment of Patients with Coronavirus Disease 2019: A Propensity Score Matching Study

The role of corticosteroids in the treatment of Coronavirus disease 2019 (COVID-19) is controversial. In the present study, we evaluated the effects of adjuvant corticosteroids treatment on the outcome of patients with COVID-19 (n=966), using Propensity Score Matching to adjust for potential differences between the corticosteroids group (n=289) and the non-corticosteroids group (n=677). Analysis of data without adjusting differences in baseline characteristics indicated that the proportion of mechanical ventilation and the mortality was higher in the corticosteroids treatment group in total or severe/critical patients. The duration of viral shedding was longer in the non-corticosteroids treatment group in total or general/mild patients. After adjusting the difference between the corticosteroids and non-corticosteroids treatment group, the analysis revealed that the use of corticosteroids had no effect on the duration of viral shedding, in-hospital mortality or 28-day mortality.

Interactions of Influenza and SARS-CoV-2 with the Lung Endothelium: Similarities, Differences, and Implications for Therapy

Respiratory viruses such as influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are a constant threat to public health given their ability to cause global pandemics. Infection with either virus may lead to aberrant host responses, such as excessive immune cell recruitment and activation, dysregulated inflammation, and coagulopathy. These may contribute to the development of lung edema and respiratory failure. An increasing amount of evidence suggests that lung endothelial cells play a critical role in the pathogenesis of both viruses. In this review, we discuss how infection with influenza or SARS-CoV-2 may induce endothelial dysfunction. We compare the effects of infection of these two viruses, how they may contribute to pathogenesis, and discuss the implications for potential treatment. Understanding the differences between the effects of these two viruses on lung endothelial cells will provide important insight to guide the development of therapeutics.

Low-to-moderate dose corticosteroids treatment in hospitalized adults with COVID-19

OBJECTIVES

Use of corticosteroids is common in the treatment of coronavirus disease 2019, but clinical effectiveness is controversial. We aimed to investigate the association of corticosteroids therapy with clinical outcomes of hospitalized COVID-19 patients.

METHODS

In this single-centre, retrospective cohort study, adult patients with confirmed coronavirus disease 2019 and dead or discharged between 29 December 2019 and 15 February 2020 were studied; 1:1 propensity score matchings were performed between patients with or without corticosteroid treatment. A multivariable COX proportional hazards model was used to estimate the association between corticosteroid treatment and in-hospital mortality by taking corticosteroids as a time-varying covariate.

RESULTS

Among 646 patients, the in-hospital death rate was higher in 158 patients with corticosteroid administration (72/158, 45.6% vs. 56/488, 11.5%, p < 0.0001). After propensity score matching analysis, no significant differences were observed in in-hospital death between patients with and without corticosteroid treatment (47/124, 37.9% vs. 47/124, 37.9%, p 1.000). When patients received corticosteroids before they required nasal high-flow oxygen therapy or mechanical ventilation, the in-hospital death rate was lower than that in patients who were not administered corticosteroids (17/86, 19.8% vs. 26/86, 30.2%, log rank p 0.0102), whereas the time from admission to clinical improvement was longer (13 (IQR 10-17) days vs. 10 (IQR 8-13) days; p < 0.001). Using the Cox proportional hazards regression model accounting for time varying exposures in matched pairs, corticosteroid therapy was not associated with mortality difference (HR 0.98, 95% CI 0.93-1.03, p 0.4694).

DISCUSSION

Corticosteroids use in COVID-19 patients may not be associated with in-hospital mortality.

Point-of-care influenza testing impacts clinical decision, patient flow and length of stay in hospitalized adults

Background

Influenza is difficult to distinguish clinically from other acute respiratory infections. Rapid laboratory diagnosis can help initiate early effective antiviral treatment and isolation. Implementing a novel point-of-care test (POCT) for influenza in the emergency department (ED) could improve treatment and isolation strategies and reduce the length of stay (LOS).

Methods

In a prospective, controlled observational cohort study, we enrolled patients admitted due to acute respiratory illness to 2 public hospitals in Bergen, Norway, one using a rapid POCT for influenza (n = 400), the other (n = 167) using conventional rapid laboratory-based assay.

Results

Prevalence of influenza was similar in the 2 hospitals (154/400, 38% vs 38%, 63/167; P = .863). Most patients in both hospitals received antiviral (83% vs 81%; P = .703) and antibiotic treatment (72% vs 62%; P = .149). Isolation was more often initiated in ED in the hospital using POCT (91% vs 80%; P = .025). Diagnosis by POCT was associated with shorter hospital stay; old age, diabetes, cancer, and use of antibiotics, particularly broad-spectrum antibiotics, were associated with prolonged stay.

Conclusions

POCT implementation in ED resulted in improved targeted isolation and shorter LOS. Regardless of POCT use, most influenza patients received antivirals (>80%) and antibiotics (>69%).

Effectiveness of oseltamivir in reduction of complications and 30-day mortality in severe seasonal influenza infection

OBJECTIVES

The benefit of oseltamivir treatment in patients admitted with influenza virus infection and the design of studies addressing this issue have been questioned extensively. As the burden of influenza disease is substantial and oseltamivir treatment is biologically plausible, this study assessed the clinical benefit of oseltamivir treatment in adult patients admitted with severe seasonal influenza virus infection in daily practice.

PATIENTS AND METHODS

A multi-centre, retrospective cohort study was conducted to compare the effectiveness of treatment with and without oseltamivir <48 h after admission in patients admitted with laboratory-confirmed influenza virus infection in three large hospitals in the Netherlands. Propensity score matching was used to compare clinically relevant outcome variables.

RESULTS

In total, 390 patients were included in this study, of whom 80% had comorbidities. Thirty-day mortality, as well as the composite endpoint of 30-day mortality or intensive care unit admission >48 h after admission, were reduced by 9% (P=0.04) and 11% (P=0.02), respectively. Length of hospital stay and in-hospital mortality rates all showed a trend towards reduction. The median duration between symptom onset and initiation of treatment was 3 days.

CONCLUSIONS

This study supports that, in daily practice, patients admitted with influenza virus infection should be treated with oseltamivir within 48 h of admission, even if they have had complaints for >48 h.

Corticosteroid administration for viral pneumonia: COVID-19 and beyond

Background

Corticosteroids are commonly used as adjuvant therapy for acute respiratory distress syndrome by many clinicians because of their perceived anti-inflammatory effects. However, for patients with severe viral pneumonia, the corticosteroid treatment is highly controversial.

Objectives

The purpose of this review is to systematically evaluate the effect and potential mechanism of corticosteroid administration in pandemic viral pneumonia.

Sources

We comprehensively searched all manuscripts on corticosteroid therapy for influenza, severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS) and SARS coronavirus 2 (SARS-CoV-2) viral pneumonia from the PubMed, EMBASE, Web of Science and Cochrane Library databases.

Content

We systematically summarized the effects of corticosteroid therapy for pandemic viral pneumonia and the potential mechanism of action for corticosteroids in coronavirus disease 2019 (COVID-19).

Implications

Observational studies showed that corticosteroid treatment was associated with increased mortality and nosocomial infections for influenza and delayed virus clearance for SARS-CoV and MERS-CoV. Limited data on corticosteroid therapy for COVID-19 were reported. Corticosteroids were used in about a fifth of patients (670/2995, 22.4%). Although clinical observational studies reported the improvement in symptoms and oxygenation for individuals with severe COVID-19 who received corticosteroid therapy, case fatality rate in the corticosteroid group was significantly higher than that in the non-corticosteroid group (69/443, 15.6% versus 56/1310, 4.3%). Compared individuals with non-severe disease, those with severe disease were more likely to receive corticosteroid therapy (201/382, 52.6% versus 201/1310, 15.3%). Although there is no evidence that corticosteroid therapy reduces mortality in people with COVID-19, some improvements in clinical symptoms and oxygenation were reported in some clinical observational studies. Excessive inflammatory response and lymphopenia might be critical factors associated with severity of and mortality from COVID-19. Sufficiently powered randomized controlled trials with rigorous inclusion/exclusion criteria and standardized dose and duration of corticosteroids are needed to verify the effectiveness and safety of corticosteroid therapy.

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.

Efficacy and safety of corticosteroids in COVID-19 based on evidence for COVID-19, other coronavirus infections, influenza, community-acquired pneumonia and acute respiratory distress syndrome: a systematic review and meta-analysis

BACKGROUND

Very little direct evidence exists on use of corticosteroids in patients with coronavirus disease 2019 (COVID-19). Indirect evidence from related conditions must therefore inform inferences regarding benefits and harms. To support a guideline for managing COVID-19, we conducted systematic reviews examining the impact of corticosteroids in COVID-19 and related severe acute respiratory illnesses.

METHODS

We searched standard international and Chinese biomedical literature databases and prepublication sources for randomized controlled trials (RCTs) and observational studies comparing corticosteroids versus no corticosteroids in patients with COVID-19, severe acute respiratory syndrome (SARS) or Middle East respiratory syndrome (MERS). For acute respiratory distress syndrome (ARDS), influenza and community-acquired pneumonia (CAP), we updated the most recent rigorous systematic review. We conducted random-effects meta-analyses to pool relative risks and then used baseline risk in patients with COVID-19 to generate absolute effects.

RESULTS

In ARDS, according to 1 small cohort study in patients with COVID-19 and 7 RCTs in non-COVID-19 populations (risk ratio [RR] 0.72, 95% confidence interval [CI] 0.55 to 0.93, mean difference 17.3% fewer; low-quality evidence), corticosteroids may reduce mortality. In patients with severe COVID-19 but without ARDS, direct evidence from 2 observational studies provided very low-quality evidence of an increase in mortality with corticosteroids (hazard ratio [HR] 2.30, 95% CI 1.00 to 5.29, mean difference 11.9% more), as did observational data from influenza studies. Observational data from SARS and MERS studies provided very low-quality evidence of a small or no reduction in mortality. Randomized controlled trials in CAP suggest that corticosteroids may reduce mortality (RR 0.70, 95% CI 0.50 to 0.98, 3.1% lower; very low-quality evidence), and may increase hyperglycemia.

INTERPRETATION

Corticosteroids may reduce mortality for patients with COVID-19 and ARDS. For patients with severe COVID-19 but without ARDS, evidence regarding benefit from different bodies of evidence is inconsistent and of very low quality.

Role of adjunctive treatment strategies in COVID-19 and a review of international and national clinical guidelines

The coronavirus disease (COVID-19) pandemic has led to a global struggle to cope with the sheer numbers of infected persons, many of whom require intensive care support or eventually succumb to the illness. The outbreak is managed by a combination of disease containment via public health measures and supportive care for those who are affected. To date, there is no specific anti-COVID-19 treatment. However, the urgency to identify treatments that could turn the tide has led to the emergence of several investigational drugs as potential candidates to improve outcome, especially in the severe to critically ill. While many of these adjunctive drugs are being investigated in clinical trials, professional bodies have attempted to clarify the setting where the use of these drugs may be considered as off-label or compassionate use. This review summarizes the clinical evidence of investigational adjunctive treatments used in COVID-19 patients as well as the recommendations of their use from guidelines issued by international and national organizations in healthcare.

Anti-Allergic and Anti-Inflammatory Effects and Molecular Mechanisms of Thioredoxin on Respiratory System Diseases

Significance: The pathogenesis and progression of allergic inflammation in the respiratory system are closely linked to oxidative stress. Thioredoxin (TRX) is an essential redox balance regulator in organisms and is induced by various oxidative stress factors, including ultraviolet rays, radiation, oxidation, viral infections, ischemia reperfusion, and anticancer agents. Recent Advances: We demonstrated that systemic administration and transgenic overexpression of TRX is useful in a wide variety of in vivo inflammatory respiratory diseases models, such as viral pneumonia, interstitial lung disease, chronic obstructive pulmonary disease, asthma, acute respiratory distress syndrome, and obstructive sleep apnea syndrome, by removing reactive oxygen species, blocking production of inflammatory cytokines, inhibiting migration and activation of neutrophils and eosinophils, and regulating the cellular redox status. In addition, TRX's anti-inflammatory mechanism is different from the mechanisms associated with anti-inflammatory agents, such as glucocorticoids, which regulate the inflammatory reaction in association with suppressing immune responses. Critical Issues: Understanding the molecular mechanism of TRX is very helpful for understanding the role of TRX in respiratory diseases. In this review, we show the protective effect of TRX in various respiratory diseases. In addition, we discuss its anti-allergic and anti-inflammatory molecular mechanism in detail. Future Directions: The application of TRX may be useful for treating respiratory allergic inflammatory disorders. Antioxid. Redox Signal. 32, 785-801.

Use of corticosteroids in influenza-associated acute respiratory distress syndrome and severe pneumonia: a systemic review and meta-analysis

Influenza-related severe pneumonia and acute respiratory distress syndrome (ARDS) are severe threats to human health. The objective of this study was to assess the effects of systematic corticosteroid therapy in patients with pneumonia or ARDS. The PubMed, EMBASE, Web of Science and SCOPUS databases were searched up to July, 2019. Nineteen studies including 6637 individuals were identified, and fifteen studies (6427 patients) were included in the meta-analysis of mortality. Eighteen were observational studies and one was a randomized controlled trial (RCT). The meta-analysis results showed that corticosteroid therapy was associated with significantly higher mortality (OR 1.53, 95% CI [1.16, 2.01]) and incidence of nosocomial infection (OR 3.15, 95% CI [1.54, 6.45]). Subgroup analysis showed that among patients with unadjusted estimates, the odds of mortality were higher in patients receiving corticosteroid treatment (OR 1.98, 95% CI [1.23, 3.17]), however, among patients with adjusted estimates, the result showed no statistically significant difference between corticosteroid group and control group (OR 1.31, 95% CI [0.95, 1.80]). Current data do not support the routine use of corticosteroids in patients with influenza severe pneumonia or ARDS. RCTs are needed to provide more robust evidence.

Corticosteroids as Adjunctive Therapy in the Treatment of Influenza: An Updated Cochrane Systematic Review and Meta-analysis

OBJECTIVES

Corticosteroids may be beneficial in sepsis, but uncertainty remains over their effects in severe influenza. This systematic review updates the current evidence regarding corticosteroids in the treatment of influenza and examines the effect of dose on outcome.

DATA SOURCES

Electronic databases (MEDLINE, EMBASE, CINAHL, LILACS, CENTRAL, and Web of Science) and trial registries were searched to October 2018 for randomized controlled trials, quasi-experimental designs, and observational cohort studies reporting corticosteroid versus no corticosteroid treatment in individuals with influenza.

STUDY SELECTION AND DATA EXTRACTION

Two researchers independently assessed studies for inclusion. Risk of bias was assessed using the Cochrane Risk of Bias tool (randomized controlled trials) or Newcastle-Ottawa Scale (observational studies). Where appropriate, we estimated the effect of corticosteroids by random-effects meta-analyses using the generic inverse variance method. Meta-regression analysis was used to assess the association of corticosteroid dose and mortality.

DATA SYNTHESIS

We identified 30 eligible studies, all observational apart from one randomized controlled trial. Twenty-one observational studies were included in the meta-analysis of mortality, which suggested an adverse association with corticosteroid therapy (odds ratio, 3.90; 95% CI, 2.31-6.60; 15 studies; adjusted hazard ratio, 1.49; 95% CI, 1.09-2.02; six studies). Risk of bias assessment was consistent with potential confounding by indication. Pooled analysis of seven studies showed increased odds of hospital-acquired infection in people treated with corticosteroids (unadjusted odds ratio, 2.74; 95% CI, 1.51-4.95). Meta-regression of the effect of dose on mortality did not reveal an association, but reported doses of corticosteroids in included studies were high (mostly > 40 mg methylprednisolone [or equivalent] per day).

CONCLUSIONS

Corticosteroid treatment in influenza is associated with increased mortality and hospital-acquired infection, but the evidence relates mainly to high corticosteroid doses and is of low quality with potential confounding by indication a major concern.

Severe flu management: a point of view

Annual flu seasons are typically characterized by changes in types and subtypes of influenza, with variations in terms of severity. Despite remarkable improvements in the prevention and management of patients with suspected or laboratory-confirmed diagnosis of influenza, annual seasonal influenza continues to be associated with a high morbidity and mortality. Admission to the intensive care unit is required for patients with severe forms of seasonal influenza infection, with primary pneumonia being present in most of the cases. This review summarizes the most recent knowledge on the diagnosis and treatment strategies in critically ill patients with influenza, focused on diagnostic testing methods, antiviral therapy, use of corticosteroids, antibacterial and antifungal therapy, and supportive measures. The review focuses on diagnostic testing methods, antiviral therapy, use of corticosteroids, antibacterial and antifungal therapy, supportive measures and relevant existing evidence, in order to provide the non-expert clinician a useful overview. An enhanced understanding of current diagnostic and treatment aspects of influenza infection can contribute to improve outcomes and reduce mortality among ICU patients with influenza.

Severe acute respiratory infection risk following glucocorticosteroid treatment in uncomplicated influenza-like illness resulting from pH1N1 influenza infection: a case control study

Background

Current studies regarding glucocorticosteroid treatment of influenza have only estimated risk of critical illness or death which can be easily confounded by timing of treatment administration. We used severe acute respiratory infection (sARI) as an endpoint and investigated risk associated with receiving glucocorticosteroids before sARI onset.

Methods

sARI cases were defined as influenza-like illness (ILI) with pH1N1 infection and respiratory distress. Controls were defined as pH1N1 cases other than sARI and randomly selected from the community. We compared glucocorticosteroids and other medications used before sARI onset using a matched case control study adjusted for age group as well as underlying disease. Time-dependent risk and dose responses at different time periods over the course of sARI cases were also examined.

Results

Of the sARI cases, 34% received glucocorticosteroids before sARI onset compared to 3.8% of controls during equivalent days (OR_M-H = 17,95%CI = 2.1–135). Receiving glucocorticosteroids before sARI onset increased risk of developing subsequent critical illness or death (OR_M-H = 5.7,95%CI = 1.6–20.2), and the OR_M-H increased from 5.7 to 8.5 for continued glucocorticosteroid use after sARI onset. However, only receiving glucocorticosteroids after sARI onset did not increase risk of severe illness (OR_M-H = 1.1,95%CI = 0.3–4.6). Each increase in glucocorticosteroids dose of 1 mg/kg/day before sARI onset resulted in an increase of 0.62 (R² = 0.87) in the pMEWS score at the time of sARI onset.

Conclusions

Early glucocorticosteroid treatment increased risk of sARI and subsequent critical illness or death; however, only receiving glucocorticosteroids after sARI onset did not increase risk of severe illness.

Recommended hospital preparations for future cases and outbreaks of novel influenza viruses

Introduction: Seasonal influenza epidemics and periodic pandemics are important causes of morbidity and mortality. Influenza transmits predominantly by respiratory droplets and fomites but opportunistic airborne transmission may occur in the hospital setting due to overcrowding, poor compliance with infection control measures, and performance of aerosol-generating procedures.Areas covered: This article reviews the risk factors of nosocomial influenza outbreaks and discusses clinical, diagnostic, and treatment aspects of seasonal and avian influenza to facilitate hospital preparations for future influenza outbreaks. Literature search was conducted through PubMed of relevant peer-reviewed full papers in English journals with inclusion of relevant publications by the WHO and US CDC.Expert opinion: Accurate and rapid identification of an influenza outbreak is important to facilitate patient care and prevent nosocomial transmission. Timely treatment with a neuraminidase inhibitor (NAI) for adults hospitalized with severe influenza is associated with lower mortality and better clinical outcomes. Baloxavir, a polymerase endonuclease inhibitor, offers a new treatment alternative and its role in combination with NAI for treatment of severe influenza is being investigated. High-dose systemic corticosteroids are associated with worse outcomes in patients with severe influenza. It is important to develop more effective antiviral and immuno-modulating therapies for the treatment of influenza infections.

Neuraminidase inhibitor resistance in influenza: a clinical perspective

PURPOSE OF REVIEW

Neuraminidase inhibitors (NAIs), including oseltamivir, zanamivir, and peramivir, is the main class of antiviral available for clinical use. As such, development of resistance toward these agents is of great clinical and public health concern.

RECENT FINDINGS

At present, NAI resistance remains uncommon among the circulating viruses (oseltamivir <3.5%, zanamivir <1%). Resistance risk is slightly higher in A(H1N1) than A(H3N2) and B viruses. Resistance may emerge during drug exposure, particularly among young children (<5 years), the immunocompromised, and individuals receiving prophylactic regimens. H275Y A(H1N1) variant, showing high-level oseltamivir resistance, is capable of causing outbreaks. R294K A(H7N9) variant shows reduced inhibition across NAIs. Multi-NAI resistance has been reported in the immunocompromised.

SUMMARY

These findings highlight the importance of continuous surveillance, and assessment of viral fitness and transmissibility of resistant virus strains. Detection can be challenging, especially in a mix of resistant and wild-type viruses. Recent advances in molecular techniques (e.g. targeted mutation PCR, iART, ddPCR, pyrosequencing, next-generation sequencing) have improved detection and our understanding of viral dynamics. Treatment options available for oseltamivir-resistant viruses are limited, and susceptibility testing of other NAIs may be required, but non-NAI antivirals (e.g. polymerase inhibitors) that are active against these resistant viruses are in late-stage clinical development.

Combined immunization with attenuated live influenza vaccine and chimeric pneumococcal recombinant protein improves the outcome of virus-bacterial infection in mice

Influenza and its bacterial complications are a leading cause of morbidity and mortality worldwide. The effect of combined immunization with live influenza vaccine and recombinant chimeric pneumococcal protein in dual infection caused by influenza H1N1 and S. pneumoniae (serotype 3) has been studied. The combined vaccine consisted of the strain A/California/2009/38 (H1N1) pdm and chimeric recombinant protein PSPF composed of immunodominant fragments of the surface virulence factors of S. pneumoniae—PsaA, PspA, and Shr1875—associated with modified salmonella flagellin. Vaccinated mice were infected with the influenza virus 24 hours before or 24 hours after the onset of pneumococcal infection. The protective effect of combined vaccination was shown on both models of viral-bacterial infection.

Corticosteroid Therapy for Critically Ill Patients with Middle East Respiratory Syndrome

RATIONALE

Corticosteroid therapy is commonly used among critically ill patients with Middle East Respiratory Syndrome (MERS), but its impact on outcomes is uncertain. Analyses of observational studies often do not account for patients' clinical condition at the time of corticosteroid therapy initiation.

OBJECTIVES

To investigate the association of corticosteroid therapy on mortality and on MERS coronavirus RNA clearance in critically ill patients with MERS.

METHODS

ICU patients with MERs were included from 14 Saudi Arabian centers between September 2012 and October 2015. We performed marginal structural modeling to account for baseline and time-varying confounders.

MEASUREMENTS AND MAIN RESULTS

Of 309 patients, 151 received corticosteroids. Corticosteroids were initiated at a median of 3.0 days (quartile 1 [Q1]-Q3, 1.0-7.0) from ICU admission. Patients who received corticosteroids were more likely to receive invasive ventilation (141 of 151 [93.4%] vs. 121 of 158 [76.6%]; P < 0.0001) and had higher 90-day crude mortality (112 of 151 [74.2%] vs. 91 of 158 [57.6%]; P = 0.002). Using marginal structural modeling, corticosteroid therapy was not significantly associated with 90-day mortality (adjusted odds ratio, 0.75; 95% confidence interval, 0.52-1.07; P = 0.12) but was associated with delay in MERS coronavirus RNA clearance (adjusted hazard ratio, 0.35; 95% CI, 0.17-0.72; P = 0.005).

CONCLUSIONS

Corticosteroid therapy in patients with MERS was not associated with a difference in mortality after adjustment for time-varying confounders but was associated with delayed MERS coronavirus RNA clearance. These findings highlight the challenges and importance of adjusting for baseline and time-varying confounders when estimating clinical effects of treatments using observational studies.

Allergic Airway Disease Prevents Lethal Synergy of Influenza A Virus-Streptococcus pneumoniae Coinfection

Asthma has become one of the most common chronic diseases and has been identified as a risk factor for developing influenza. However, the impact of asthma on postinfluenza secondary bacterial infection is currently not known. Here, we developed a novel triple-challenge model of allergic airway disease, primary influenza infection, and secondary Streptococcus pneumoniae infection to investigate the impact of asthma on susceptibility to viral-bacterial coinfections. We report for the first time that mice recovering from acute allergic airway disease are highly resistant to influenza-pneumococcal coinfection and that this resistance is due to inhibition of influenza virus-mediated impairment of bacterial clearance. Further characterization of allergic airway disease-associated resistance against postinfluenza secondary bacterial infection may aid in the development of prophylactic and/or therapeutic treatment against coinfection.

Fatal outcomes following influenza infection are often associated with secondary bacterial infections. Allergic airway disease (AAD) is known to influence severe complications from respiratory infections, and yet the mechanistic effect of AAD on influenza virus-Streptococcus pneumoniae coinfection has not been investigated previously. We examined the impact of AAD on host susceptibility to viral-bacterial coinfections. We report that AAD improved survival during coinfection when viral-bacterial challenge occurred 1 week after AAD. Counterintuitively, mice with AAD had significantly deceased proinflammatory responses during infection. Specifically, both CD4⁺ and CD8⁺ T cell interferon gamma (IFN-γ) responses were suppressed following AAD. Resistance to coinfection was also associated with strong transforming growth factor β1 (TGF-β1) expression and increased bacterial clearance. Treatment of AAD mice with IFN-γ or genetic deletion of TGF-β receptor II expression reversed the protective effects of AAD. Using a novel triple-challenge model system, we show for the first time that AAD can provide protection against influenza virus-S. pneumoniae coinfection through the production of TGF-β that suppresses the influenza virus-induced IFN-γ response, thereby preserving antibacterial immunity.

Influenza virus-related critical illness: prevention, diagnosis, treatment

Annual seasonal influenza epidemics of variable severity result in significant morbidity and mortality in the United States (U.S.) and worldwide. In temperate climate countries, including the U.S., influenza activity peaks during the winter months. Annual influenza vaccination is recommended for all persons in the U.S. aged 6 months and older, and among those at increased risk for influenza-related complications in other parts of the world (e.g. young children, elderly). Observational studies have reported effectiveness of influenza vaccination to reduce the risks of severe disease requiring hospitalization, intensive care unit admission, and death. A diagnosis of influenza should be considered in critically ill patients admitted with complications such as exacerbation of underlying chronic comorbidities, community-acquired pneumonia, and respiratory failure during influenza season. Molecular tests are recommended for influenza testing of respiratory specimens in hospitalized patients. Antigen detection assays are not recommended in critically ill patients because of lower sensitivity; negative results of these tests should not be used to make clinical decisions, and respiratory specimens should be tested for influenza by molecular assays. Because critically ill patients with lower respiratory tract disease may have cleared influenza virus in the upper respiratory tract, but have prolonged influenza viral replication in the lower respiratory tract, an endotracheal aspirate (preferentially) or bronchoalveolar lavage fluid specimen (if collected for other diagnostic purposes) should be tested by molecular assay for detection of influenza viruses.Observational studies have reported that antiviral treatment of critically ill adult influenza patients with a neuraminidase inhibitor is associated with survival benefit. Since earlier initiation of antiviral treatment is associated with the greatest clinical benefit, standard-dose oseltamivir (75 mg twice daily in adults) for enteric administration is recommended as soon as possible as it is well absorbed in critically ill patients. Based upon observational data that suggest harms, adjunctive corticosteroid treatment is currently not recommended for children or adults hospitalized with influenza, including critically ill patients, unless clinically indicated for another reason, such as treatment of asthma or COPD exacerbation, or septic shock. A number of pharmaceutical agents are in development for treatment of severe influenza.

Influenza virus-related critical illness: prevention, diagnosis, treatment

Annual seasonal influenza epidemics of variable severity result in significant morbidity and mortality in the United States (U.S.) and worldwide. In temperate climate countries, including the U.S., influenza activity peaks during the winter months. Annual influenza vaccination is recommended for all persons in the U.S. aged 6 months and older, and among those at increased risk for influenza-related complications in other parts of the world (e.g. young children, elderly). Observational studies have reported effectiveness of influenza vaccination to reduce the risks of severe disease requiring hospitalization, intensive care unit admission, and death. A diagnosis of influenza should be considered in critically ill patients admitted with complications such as exacerbation of underlying chronic comorbidities, community-acquired pneumonia, and respiratory failure during influenza season. Molecular tests are recommended for influenza testing of respiratory specimens in hospitalized patients. Antigen detection assays are not recommended in critically ill patients because of lower sensitivity; negative results of these tests should not be used to make clinical decisions, and respiratory specimens should be tested for influenza by molecular assays. Because critically ill patients with lower respiratory tract disease may have cleared influenza virus in the upper respiratory tract, but have prolonged influenza viral replication in the lower respiratory tract, an endotracheal aspirate (preferentially) or bronchoalveolar lavage fluid specimen (if collected for other diagnostic purposes) should be tested by molecular assay for detection of influenza viruses.Observational studies have reported that antiviral treatment of critically ill adult influenza patients with a neuraminidase inhibitor is associated with survival benefit. Since earlier initiation of antiviral treatment is associated with the greatest clinical benefit, standard-dose oseltamivir (75 mg twice daily in adults) for enteric administration is recommended as soon as possible as it is well absorbed in critically ill patients. Based upon observational data that suggest harms, adjunctive corticosteroid treatment is currently not recommended for children or adults hospitalized with influenza, including critically ill patients, unless clinically indicated for another reason, such as treatment of asthma or COPD exacerbation, or septic shock. A number of pharmaceutical agents are in development for treatment of severe influenza.

The effect of corticosteroids on mortality of patients with influenza pneumonia: a systematic review and meta-analysis

Background

The effect of corticosteroids on clinical outcomes in patients with influenza pneumonia remains controversial. We aimed to further evaluate the influence of corticosteroids on mortality in adult patients with influenza pneumonia by comparing corticosteroid-treated and placebo-treated patients.

Methods

The PubMed, Embase, Medline, Cochrane Central Register of Controlled Trials (CENTRAL), and Information Sciences Institute (ISI) Web of Science databases were searched for all controlled studies that compared the effects of corticosteroids and placebo in adult patients with influenza pneumonia. The primary outcome was mortality, and the secondary outcomes were mechanical ventilation (MV) days, length of stay in the intensive care unit (ICU LOS), and the rate of secondary infection.

Results

Ten trials involving 6548 patients were pooled in our final analysis. Significant heterogeneity was found in all outcome measures except for ICU LOS (I² = 38%, P = 0.21). Compared with placebo, corticosteroids were associated with higher mortality (risk ratio [RR] 1.75, 95% confidence interval [CI] 1.30 ~ 2.36, Z = 3.71, P = 0.0002), longer ICU LOS (mean difference [MD] 2.14, 95% CI 1.17 ~ 3.10, Z = 4.35, P < 0.0001), and a higher rate of secondary infection (RR 1.98, 95% CI 1.04 ~ 3.78, Z = 2.08, P = 0.04) but not MV days (MD 0.81, 95% CI − 1.23 ~ 2.84, Z = 0.78, P = 0.44) in patients with influenza pneumonia.

Conclusions

In patients with influenza pneumonia, corticosteroid use is associated with higher mortality.

Trial registration

PROSPERO (ID: CRD42018112384).

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2395-8) contains supplementary material, which is available to authorized users.

Clinical Practice Guidelines by the Infectious Diseases Society of America: 2018 Update on Diagnosis, Treatment, Chemoprophylaxis, and Institutional Outbreak Management of Seasonal Influenzaa

These clinical practice guidelines are an update of the guidelines published by the Infectious Diseases Society of America (IDSA) in 2009, prior to the 2009 H1N1 influenza pandemic. This document addresses new information regarding diagnostic testing, treatment and chemoprophylaxis with antiviral medications, and issues related to institutional outbreak management for seasonal influenza. It is intended for use by primary care clinicians, obstetricians, emergency medicine providers, hospitalists, laboratorians, and infectious disease specialists, as well as other clinicians managing patients with suspected or laboratory-confirmed influenza. The guidelines consider the care of children and adults, including special populations such as pregnant and postpartum women and immunocompromised patients.

Clinical Practice Guidelines by the Infectious Diseases Society of America: 2018 Update on Diagnosis, Treatment, Chemoprophylaxis, and Institutional Outbreak Management of Seasonal Influenzaa

These clinical practice guidelines are an update of the guidelines published by the Infectious Diseases Society of America (IDSA) in 2009, prior to the 2009 H1N1 influenza pandemic. This document addresses new information regarding diagnostic testing, treatment and chemoprophylaxis with antiviral medications, and issues related to institutional outbreak management for seasonal influenza. It is intended for use by primary care clinicians, obstetricians, emergency medicine providers, hospitalists, laboratorians, and infectious disease specialists, as well as other clinicians managing patients with suspected or laboratory-confirmed influenza. The guidelines consider the care of children and adults, including special populations such as pregnant and postpartum women and immunocompromised patients.

Corticosteroids as adjunctive therapy in the treatment of influenza

BACKGROUND

Specific treatments for influenza are limited to neuraminidase inhibitors and adamantanes. Corticosteroids show evidence of benefit in sepsis and related conditions, most likely due to their anti-inflammatory and immunomodulatory properties. Although commonly prescribed for severe influenza, there is uncertainty over their potential benefits or harms. This is an update of a review first published in 2016.

OBJECTIVES

To systematically assess the effectiveness and potential adverse effects of corticosteroids as adjunctive therapy in the treatment of influenza, taking into account differences in timing and doses of corticosteroids.

SEARCH METHODS

We searched CENTRAL (2018, Issue 9), which includes the Cochrane Acute Respiratory infections Group's Specialised Register, MEDLINE (1946 to October week 1, 2018), Embase (1980 to 3 October 2018), CINAHL (1981 to 3 October 2018), LILACS (1982 to 3 October 2018), Web of Science (1985 to 3 October 2018), abstracts from the last three years of major infectious disease and microbiology conferences, and references of included articles. We also searched the World Health Organization International Clinical Trials Registry Platform, ClinicalTrials.gov, and the ISRCTN registry on 3 October 2018.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), quasi-RCTs, and observational studies that compared corticosteroid treatment with no corticosteroid treatment for influenza or influenza-like illness. We did not restrict studies by language of publication, influenza subtypes, clinical setting, or age of participants. We selected eligible studies in two stages: sequential examination of title and abstract, followed by full text.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias. We pooled estimates of effect using a random-effects model, where appropriate. We assessed heterogeneity using the I² statistic and assessed the certainty of the evidence using the GRADE framework.

MAIN RESULTS

This updated review includes 30 studies (one RCT with two arms and 29 observational studies) with a total of 99,224 participants. We included 19 studies in the original review (n = 3459), all of which were observational, with 13 studies included in the meta-analysis for mortality. We included 12 new studies in this update (one RCT and 11 observational studies), and excluded one study in the original review as it has been superceded by a more recent analysis. Twenty-one studies were included in the meta-analysis (9536 individuals), of which 15 studied people infected with 2009 influenza A H1N1 virus (H1N1pdm09). Data specific to mortality were of very low quality, based predominantly on observational studies, with inconsistent reporting of variables potentially associated with the outcomes of interest, differences between studies in the way in which they were conducted, and with the likelihood of potential confounding by indication. Reported doses of corticosteroids used were high, and indications for their use were not well reported. On meta-analysis, corticosteroid therapy was associated with increased mortality (odds ratio (OR) 3.90, 95% confidence interval (CI) 2.31 to 6.60; I² = 68%; 15 studies). A similar increase in risk of mortality was seen in a stratified analysis of studies reporting adjusted estimates (OR 2.23, 95% CI 1.54 to 3.24; I² = 0%; 5 studies). An association between corticosteroid therapy and increased mortality was also seen on pooled analysis of six studies which reported adjusted hazard ratios (HRs) (HR 1.49, 95% CI 1.09 to 2.02; I² = 69%). Increased odds of hospital-acquired infection related to corticosteroid therapy were found on pooled analysis of seven studies (pooled OR 2.74, 95% CI 1.51 to 4.95; I² = 90%); all were unadjusted estimates, and we graded the data as of very low certainty.

AUTHORS' CONCLUSIONS

We found one RCT of adjunctive corticosteroid therapy for treating people with community-acquired pneumonia, but the number of people with laboratory-confirmed influenza in the treatment and placebo arms was too small to draw conclusions regarding the effect of corticosteroids in this group, and we did not include it in our meta-analyses of observational studies. The certainty of the available evidence from observational studies was very low, with confounding by indication a major potential concern. Although we found that adjunctive corticosteroid therapy is associated with increased mortality, this result should be interpreted with caution. In the context of clinical trials of adjunctive corticosteroid therapy in sepsis and pneumonia that report improved outcomes, including decreased mortality, more high-quality research is needed (both RCTs and observational studies that adjust for confounding by indication). The currently available evidence is insufficient to determine the effectiveness of corticosteroids for people with influenza.

Severe acute respiratory infections (SARI) from influenza in adult patients in Chile: the experience of a sentinel hospital

Objective

To 1) describe clinical characteristics of adult patients in Chile with severe acute respiratory infections (SARI) associated with influenza viruses, and 2) analyze virus subtypes identified in specimens collected from those patients, hospital resources used in clinical management, clinical evolution, and risk factors associated with a fatal outcome, using observational data from the SARI surveillance network (SARInet).

Methods

Adults hospitalized from 1 July 2011 to 31 December 2015 with influenza-associated SARI at a SARI sentinel surveillance hospital in Santiago were identified and the presence of influenza in all cases confirmed by reverse transcription polymerase chain reaction (RT-PCR), using respiratory samples.

Results

A total of 221 patients (mean age: 74.1 years) were hospitalized with influenza-associated SARI during the study period. Of this study cohort, 91.4% had risk factors for complications and 34.3% had been vaccinated during the most recent campaign. Pneumonia was the most frequent clinical manifestation, occurring in 57.0% of the cohort; other manifestations included influenza-like illness, exacerbated chronic bronchitis, decompensated heart failure, and asthmatic crisis. Cases occurred year-round, with an epidemic peak during autumn–winter. Both influenza A (H1N1pdm09 and H3N2) and B virus co-circulated. Critical care beds were required for 26.7% of the cohort, and 19.5% needed ventilatory assistance. Multivariate analysis identified four significant factors associated with in-hospital mortality: 1) being bedridden (adjusted odds ratio (aOR): 22.3; 95% confidence interval (CI): 3.0–164); 2) admission to critical care unit (aOR: 8.9; CI: 1.44–55); 3) Pa0₂/Fi0₂ ratio < 250 (aOR: 5.8; CI: 1.02–33); and 4) increased serum creatinine concentration (> 1 mg/dL) (aOR: 5.47; CI: 1.20–24). Seasonal influenza vaccine was identified as a significant protective factor (aOR: 0.14; CI: 0.021–0.90).

Conclusions

Influenza-associated SARI affected mainly elderly patients with underlying conditions. Most patients evolved to respiratory failure and more than one-quarter required critical care beds. Clinical presentation was variable. Death was associated with host characteristics and disease-associated conditions, and vaccine was protective. Virus type did not influence outcome.

Delayed oseltamivir plus sirolimus treatment attenuates H1N1 virus-induced severe lung injury correlated with repressed NLRP3 inflammasome activation and inflammatory cell infiltration

Severe influenza A virus infection causes high mortality and morbidity worldwide due to delayed antiviral treatment and inducing overwhelming immune responses, which contribute to immunopathological lung injury. Sirolimus, an inhibitor of mammalian target of rapamycin (mTOR), was effective in improving clinical outcomes in patients with severe H1N1 infection; however, the mechanisms by which it attenuates acute lung injury have not been elucidated. Here, delayed oseltamivir treatment was used to mimic clinical settings on lethal influenza A (H1N1) pdm09 virus (pH1N1) infection mice model. We revealed that delayed oseltamivir plus sirolimus treatment protects mice against lethal pH1N1 infection by attenuating severe lung damage. Mechanistically, the combined treatment reduced viral titer and pH1N1-induced mTOR activation. Subsequently, it suppressed the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-mediated secretion of interleukin (IL)-1β and IL-18. It was noted that decreased NLRP3 inflammasome activation was associated with inhibited nuclear factor (NF)-κB activation, reduced reactive oxygen species production and increased autophagy. Additionally, the combined treatment reduced the expression of other proinflammatory cytokines and chemokines, and decreased inflammatory cell infiltration in lung tissue and bronchioalveolar lavage fluid. Consistently, it inhibited the mTOR-NF-κB-NLRP3 inflammasome-IL-1β axis in a lung epithelial cell line. These results demonstrated that combined treatment with sirolimus and oseltamivir attenuates pH1N1-induced severe lung injury, which is correlated with suppressed mTOR-NLRP3-IL-1β axis and reduced viral titer. Therefore, treatment with sirolimus as an adjuvant along with oseltamivir may be a promising immunomodulatory strategy for managing severe influenza.

The severity and lethality of influenza A virus infection are frequently aggravated by virus-induced tissue destruction and overwhelming immune responses. Combined therapy with antiviral medications and immunomodulators, which not only inhibit viral replication, but also reduce the damaging consequences of host immune responses, will be beneficial in the treatment of severe influenza. In the present study, we revealed that pH1N1-induced activation of mTOR promotes lung immunopathological injury, which is correlated with upregulated NF-κB activity and increased reactive oxygen species production. Subsequently, it induces NLRP3 inflammasome activation and the secretion of IL-1β and IL-18. Combined treatment with oseltamivir and the mTOR inhibitor sirolimus (as an adjuvant) not only blocks viral replication, but also suppresses mTOR-NLRP3-IL-1β axis-mediated immune damage, thus protecting mice against lethal pH1N1 infection. Our findings provide the theoretical and experimental basis for the clinical investigation of sirolimus as an adjunct treatment for severe influenza.