Viral infection in adults hospitalized with community-acquired pneumonia: prevalence, pathogens, and presentation

A Retrospective Cross-Sectional Analysis of Viral SARI in Pregnant Women in Southern Brazil

Pregnant women (PW) are at a higher risk of diseases and hospitalization from viral respiratory infections, particularly influenza and SARS-CoV-2, due to cardiopulmonary and immunological changes. This study assessed the impact of viral respiratory infections on PW hospitalized with severe acute respiratory infection (SARI) prior to the COVID-19 pandemic. It is a cross-sectional study with 42 PW and 85 non-pregnant women (NPW) admitted with SARI to two tertiary hospitals between January 2015 and December 2019. The rates of virus prevalence, SARI hospitalization, length of hospital stay, oxygen supplementation, intensive care unit (ICU) admission, and death were comparable between PW and NPW. A multivariate analysis showed that PW had a higher rate of viral SARI hospitalizations (OR = 2.37; 95% CI = 1.02-5.48) as compared to NPW, with the influenza virus being the most prevalent (aOR = 7.58; 95% CI = 1.53-37.66). The length of hospital stays (aOR = 0.83; 95% CI = 0.73-0.95) and admissions to the ICU (aOR = 0.028; 95% CI = 0.004-0.25) were lower in PW as compared to hospitalized NPW. The influenza virus had a greater impact on the frequency of SARI in the group of PW, and these had a better outcome than NPW due to the earlier antiviral treatment they received.

Multiplex PCR for respiratory bacteria in acute care

The purpose of the study was to evaluate the clinical utility of multiplex PCR for detecting bacterial respiratory pathogens in nasopharyngeal samples. Acutely ill adults in the emergency department with respiratory infection symptoms, fever, chest pain or poor general condition were enrolled for this cohort study. Samples were stored at -70 °C until being analysed with multiplex PCR for seven respiratory bacteria. Of the 912 patients enrolled, those with positive bacterial samples (n = 130, 14%) were significantly younger than those with a negative finding (55.5 years vs 62.2 years, p < 0.001), and their mean C-reactive protein (CRP) concentration was higher (110 mg/L vs 59 mg/L, p < 0.0001). Patients with a positive respiratory bacterial finding had a higher probability of pneumonia (35% vs 13%, p < 0.001) and a higher likelihood of receiving a prescription for antibiotics than those with a negative finding (79% vs 59%, p < 0.0001). Positive detection of Streptococcus pneumoniae was associated with a 4.5-fold risk of pneumonia in a multivariate model and detection of an atypical respiratory pathogen with a 9-fold risk. Bacterial PCR performed on nasopharyngeal samples appeared to offer a valuable addition to the diagnostics of infections in adults in acute care.

Changes in respiratory infection trends during the COVID-19 pandemic in patients with haematologic malignancy

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic has changed respiratory infection patterns globally. However, its impact on community-acquired pneumonia (CAP) in high-risk patients with haematological malignancies (HM) is uncertain. We aimed to examine how community-acquired pneumonia aetiology in patients with haematological malignancies changed during the COVID-19 pandemic.

METHODS

This was a retrospective study that included 524 patients with haematological malignancies hospitalised with community-acquired pneumonia between March 2018 and February 2022. Patients who underwent bronchoscopy within 24 h of admission to identify community-acquired pneumonia aetiology were included. Data on patient characteristics, laboratory findings, and results of bronchioalveolar lavage fluid cultures and polymerase chain reaction tests were analysed and compared to identify changes and in-hospital mortality risk factors.

RESULTS

Patients were divided into the 'pre-COVID-19 era' (44.5%) and 'COVID-19 era' (55.5%) groups. The incidence of viral community-acquired pneumonia significantly decreased in the COVID-19 era, particularly for influenza A, parainfluenza, adenovirus, and rhinovirus (pre-COVID-19 era vs. COVID-19 era: 3.0% vs. 0.3%, P = 0.036; 6.5% vs. 0.7%, P = 0.001; 5.6% vs. 1.4%, P = 0.015; and 9.5% vs. 1.7%, P < 0.001, respectively), whereas that of bacterial, fungal, and unknown community-acquired pneumonia aetiologies remain unchanged. Higher Sequential Organ Failure Assessment scores and lower platelet counts correlated with in-hospital mortality after adjusting for potential confounding factors.

CONCLUSIONS

In the COVID-19 era, the incidence of community-acquired pneumonia with viral aetiologies markedly decreased among patients with haematological malignancies, with no changes in the incidence of bacterial and fungal pneumonia. Further studies are required to evaluate the impact of COVID-19 on the prognosis of patients with haematological malignancies and community-acquired pneumonia.

A Case Report of Sepsis-Induced Dilated Cardiomyopathy Secondary to Human Metapneumovirus Infection

Sepsis is a medical emergency that describes the body's systemic immunological response to an infectious process that can lead to end-stage organ dysfunction and death. Sepsis-induced cardiomyopathy (SICM) is an increasingly recognized form of transient cardiac dysfunction characterized by left ventricular dilation, depressed ejection fraction, and recovery in 10 days without cardiac-related medical intervention. Injury to the myocardium by inflammatory cytokines has been proposed as one of the main causative mechanisms. Human metapneumovirus (hMPV) is a paramyxovirus and a common cause of respiratory tract infection that has been reported to modulate chemical mediators that produce inflammatory cytokines. Extra-pulmonary cardiac complications of hMPV have been reported; but literature on SICM associated with hMPV are very rare. We describe a case of a 43-year-old male with no known cardiac history diagnosed with SICM associated with hMPV. His sepsis was managed in the intensive care unit, and his heart ejection fraction improved within 10 days without the initiation of guideline-directed medical therapy.

Impact of FilmArray respiratory panel test for hospitalized pediatric respiratory tract infection in Taiwan: A 3-year single-center cohort study

Respiratory tract infections are prevalent and clinically significant in pediatric populations globally. However, pathogen testing often involves time-consuming processes, resulting in delays in diagnosis. To date, commercial testing machines, such as the FilmArray respiratory panel, have been proposed for hospitals. Therefore, this study aimed to investigate the impact of the FilmArray respiratory panel at a single center. This study utilized the medical records of our hospital to select pediatric inpatients with respiratory tract infections who underwent the FilmArray respiratory panel between September 2020 and April 2021 and those who did not undergo nucleic acid detection (a rapid test group) between September 2019 and April 2020. FilmArray is a polymerase chain reaction-based diagnostic tool. The FilmArray respiratory panel group was scheduled to recruit 150 patients (final 137 patients), whereas the rapid test group was scheduled to recruit 300 patients (final 267 patients). Differences in continuous variables between the 2 groups were analyzed using independent Student t tests. The FilmArray respiratory panel group had a longer length of inpatient days, longer duration of antibiotic use, and higher proportion of pathogens that tested positive, with significant differences than those in the rapid test group. Fever duration showed no significant difference between the 2 groups. For the polymerase chain reaction method, respiratory syncytial virus was the most commonly detected pathogen causing pneumonia, followed by human rhinovirus/enterovirus and parainfluenza virus. Mycoplasma was detected using the rapid test but not with the FilmArray respiratory panel. The FilmArray respiratory panel provides clinicians with a rapid and useful diagnostic tool. The effect was quite good for virus detection, but not for bacteria. Given its limited adoption, the tool may not aid clinicians in the diagnosis of mild cases.

Patterns and predictors of positive multiplex polymerase chain reaction respiratory panel among patients with acute respiratory infections in a single center in Lebanon

BACKGROUND

Infectious agents associated with community-acquired acute respiratory infections (ARIs) remain understudied in Lebanon. We aim to assess the microbiological profiles of ARIs by employing polymerase chain reaction (PCR) and identifying predictors of positive PCR results among patients admitted for ARI.

METHODS AND RESULTS

We conducted a retrospective single-center study at the American University of Beirut Medical Center, including all respiratory PCR panels performed on pediatric (< 18) and adult (≥ 18) patients presenting with an ARI from January 2015 to March 2018, prior to the onset of the COVID-19 pandemic. We aimed to identify the epidemiological patterns of ARIs and the factors associated with positive PCRs in both adult and pediatric patients. Among 281 respiratory PCRs, 168 (59.7%) were positive for at least one pathogen, with 54.1% positive PCR for viruses, 7.8% for bacteria species, and 3.9% with virus-bacteria codetection. Almost 60% of the patients received antibiotics prior to PCR testing. PCR panels yielded more positive results in pediatric patients than in adults (P = 0.005). Bacterial detection was more common in adults compared to pediatrics (P < 0.001). The most common organism recovered in the entire population was Human Rhinovirus (RhV) (18.5%). Patients with pleural effusion on chest CT were less likely to have a positive PCR (95% Cl: 0.22-0.99). On multivariate analysis, pediatric age group (P < 0.001), stem cell transplant (P = 0.006), fever (P = 0.03) and UTRI symptoms (P = 0.004) were all predictive of a positive viral PCR.

CONCLUSION

Understanding the local epidemiology of ARI is crucial for proper antimicrobial stewardship. The identification of factors associated with positive respiratory PCR enhances our understanding of clinical characteristics and potential predictors of viral detection in our population.

Impact of viral detection in patients with community-acquired pneumonia: An observational cohort study

PURPOSE

The presence of a respiratory virus in patients with community-acquired pneumonia (CAP) may have an impact on the bacterial etiology and clinical presentation. In this study we aimed to assess the role of viral infection in the bacterial etiology and outcomes of patients with CAP.

METHODS

We performed a retrospective study of all adults hospitalized with CAP between November 2017 and October 2018. Patients were classified according to the presence of viral infection. An unvaried and a multivaried analysis were performed to identify variables associated with viral infection and clinical outcomes.

RESULTS

Overall 590 patients were included. A microorganism was documented in 375 cases (63.5%). A viral infection was demonstrated in 118 (20%). The main pathogens were Streptococcus pneumoniae (35.8%), Staphylococcus aureus (2.9%) and influenza virus (10.8%). A trend to a higher rate of S. aureus (p=0.06) in patients with viral infection was observed. Patients with viral infection had more often bilateral consolidation patterns (17.8% vs 10.8%, p=0.04), respiratory failure (59.3% vs 42.8%, p=0.001), ICU admission (17.8% vs 7%, p=0.001) and invasive mechanical ventilation (9.3% vs 2.8%, p=0.003). Risk factors for respiratory failure were chronic lung disease, age >65 years, positive blood cultures and viral infection. Influenza, virus but no other respiratory viruses, was associated with respiratory failure (OR, 3.72; 95% CI, 2.06-6.73).

CONCLUSIONS

Our study reinforces the idea that co-viral infection has an impact in the clinical presentation of CAP causing a more severe clinical picture. This impact seems to be mainly due to influenza virus infection.

Rapid, Point-of-Care Host-Based Gene Expression Diagnostics Using Giant Magnetoresistive Biosensors

Host-based gene expression analysis is a promising tool for a broad range of clinical applications, including rapid infectious disease diagnostics and real-time disease monitoring. However, the complex instrumentation requirements and slow turnaround-times associated with traditional gene expression analysis methods have hampered their widespread adoption at the point-of-care (POC). To overcome these challenges, we have developed an automated and portable platform that utilizes polymerase chain reaction (PCR) and giant magnetoresistive (GMR) biosensors to perform rapid multiplexed, targeted gene expression analysis at the POC. As proof-of-concept, we utilized our platform to amplify and measure the expression of four genes (HERC5, HERC6, IFI27, and IFIH1) that were previously shown to be upregulated in hosts infected with influenza viruses. The compact instrument conducted highly automated PCR amplification and GMR detection to measure the expression of the four genes in multiplex, then utilized Bluetooth communication to relay results to users on a smartphone application. To validate the platform, we tested 20 cDNA samples from symptomatic patients that had been previously diagnosed as either influenza-positive or influenza-negative using a RT-PCR virology panel. A non-parametric Mann-Whitney test revealed that day 0 (day of symptom onset) gene expression was significantly different between the two groups (p < 0.0001, n = 20). Hence, we preliminarily demonstrated that our platform could accurately discriminate between symptomatic influenza and non-influenza populations based on host gene expression in ∼30 min. This study not only establishes the potential clinical utility of our proposed assay and device for influenza diagnostics but it also paves the way for broadscale and decentralized implementation of host-based gene expression diagnostics at the POC.

Impact of Pneumococcal and Viral Pneumonia on the Respiratory and Intestinal Tract Microbiomes of Mice

With 2.56 million deaths worldwide annually, pneumonia is one of the leading causes of death. The most frequent causative pathogens are Streptococcus pneumoniae and influenza A virus. Lately, the interaction between the pathogens, the host, and its microbiome have gained more attention. The microbiome is known to promote the immune response toward pathogens; however, our knowledge on how infections affect the microbiome is still scarce. Here, the impact of colonization and infection with S. pneumoniae and influenza A virus on the structure and function of the respiratory and gastrointestinal microbiomes of mice was investigated. Using a meta-omics approach, we identified specific differences between the bacterial and viral infection. Pneumococcal colonization had minor effects on the taxonomic composition of the respiratory microbiome, while acute infections caused decreased microbial complexity. In contrast, richness was unaffected following H1N1 infection. Within the gastrointestinal microbiome, we found exclusive changes in structure and function, depending on the pathogen. While pneumococcal colonization had no effects on taxonomic composition of the gastrointestinal microbiome, increased abundance of Akkermansiaceae and Spirochaetaceae as well as decreased amounts of Clostridiaceae were exclusively found during invasive S. pneumoniae infection. The presence of Staphylococcaceae was specific for viral pneumonia. Investigation of the intestinal microbiomés functional composition revealed reduced expression of flagellin and rubrerythrin and increased levels of ATPase during pneumococcal infection, while increased amounts of acetyl coenzyme A (acetyl-CoA) acetyltransferase and enoyl-CoA transferase were unique after H1N1 infection. In conclusion, identification of specific taxonomic and functional profiles of the respiratory and gastrointestinal microbiome allowed the discrimination between bacterial and viral pneumonia. IMPORTANCE Pneumonia is one of the leading causes of death worldwide. Here, we compared the impact of bacterial- and viral-induced pneumonia on the respiratory and gastrointestinal microbiome. Using a meta-omics approach, we identified specific profiles that allow discrimination between bacterial and viral causative.

Lower Respiratory Tract Coinfection in the ICU: Prevalence and Clinical Significance of Coinfection Detected via Microbiological Analysis of Bronchoalveolar Lavage Fluid With a Comparison of Invasive Methodologies

Pneumonia remains a significant cause of morbidity and mortality, with increasing interest in the detection and clinical significance of coinfection. Further investigation into the impact of bronchoalveolar lavage (BAL) sampling methodology and efficient clinical utilization of microbiological analyses is needed to guide the management of lower respiratory tract infection in the ICU.

Mapping theme trends and recognizing hot spots in viral pneumonia: a bibliometric analysis of global research

BACKGROUND

The challenges that viral pneumonia poses to the global public health system remain daunting. In this study, an analysis of publications on viral pneumonia over the past two decades was conducted. Through this work, we hope to provide inspiration for future research on viral pneumonia.

METHODS

We extracted all of the English publications relevant to viral pneumonia published during 1999-2019 from Web of Science. GraphPad Prism, CiteSpace, and VOSviewer were used to collect and analyze the publication trends in related fields.

RESULTS

We identified 2,006 publications with 62,155 citations as of February 16, 2021. The United States accounted for the largest number of publications (34.2%), with the highest number of citations (27,616) and the highest h-index (78). China ranked second in the number of publications. Ctr Dis Control & Prevent proved to be the center of research cooperation. Clinical Infectious Diseases included the most papers published relating to the topic of viral pneumonia. Chan KH published the most papers in this field (25), while an article from Fouchier RAM presented the highest citation frequency (1,275).

CONCLUSIONS

According to the bibliometric analysis database and related software results, the United States dominates the field of viral pneumonia research. The key term extracted by VOSviewer has shifted to "Diagnosis and management", indicating a new trend for viral pneumonia research.

Community-Acquired Pneumonia in Canada During COVID-19

Dealing with coronavirus disease 2019 (COVID-19) has been a monumental test of medical skills and resources worldwide. The management of community-acquired pneumonia (CAP) can at times be difficult, but treating CAP in the setting of COVID-19 can be particularly trying and confusing and raises a number of challenging questions relating to etiology, diagnosis, and treatment. This article is based on the authors’ experiences and presents an overview of how CAP during COVID-19 is handled in Canada. We touch on the issues of microbial etiology in patients with CAP in the setting of COVID-19 as well as diagnostic, site of care, and treatment approaches. Published guidelines are the basis of management of CAP and are discussed in the context of Canadian data. We also outline the usual treatment approaches to COVID-19, particularly in patients who have been hospitalized.

Multipathogen Detection in Patients with Respiratory Tract Infection: Identification of Non-respiratory Viruses Using Multiplex Real-time Polymerase Reaction

Background: Due to the overlapping clinical characteristics of respiratory tract infections (RTIs) and the unavailability of appropriate diagnostic techniques, the diagnosis of RTIs is controversial. Objectives: The study aimed to prompt the diagnosis of RTIs using commercial multiplex real-time PCR. Methods: The survey undertook for two years (2019 - 2020) on 144 flu-negative immunocompetent outpatients. Respiratory samples were examined by multiplex PCR assays. Results: Study population consisted of females (n = 77, 53.5%) and males (n = 67, 46.5%). The mean age was 42.8 ± 23.7 years. Thirty-one (21.5%) patients were infected with only one viral or bacterial infection. Eighty-two (57%) were infected with more than one pathogen. Ninety-five (37%) and 161 (62%) tests were positive for bacterial and viral pathogens, respectively. Community-acquired Pneumonia (CAP) and atypical CAP pathogens included 17% and 10% of respiratory specimens, respectively. The predominant pathogens consisted of Human Herpes Virus 7 (HHV-7) (n = 38, 15.5%), Epstein-Barr Virus (EBV) (n = 34, 13.8%), Mycoplasma pneumoniae (n = 24, 9.8%), and Human Herpes Virus 6 (HHV-6) (n = 21, 8.5%). There were associations between pathogen findings and special age categories. Fever, cough, dyspnea, and hemoptysis were associated with certain pathogens. There was no substantial difference between viral and bacterial Ct concerning gender, age group, and comorbidities. Conclusions: Multiplex diagnostic assays significantly increased the rate of appropriate diagnosis of respiratory pathogens. However, further investigation is needed to find non-respiratory viruses' significance in respiratory specimens of immunocompetent symptomatic patients.

Parainfluenza Virus Types 1-3 Infections Among Children and Adults Hospitalized With Community-acquired Pneumonia

BACKGROUND

Parainfluenza virus (PIV) is a leading cause of lower respiratory tract infections. Although there are several distinct PIV serotypes, few studies have compared the clinical characteristics and severity of infection among the individual PIV serotypes and between PIV and other pathogens in patients with community-acquired pneumonia.

METHODS

We conducted active population-based surveillance for radiographically confirmed community-acquired pneumonia hospitalizations among children and adults in 8 US hospitals with systematic collection of clinical data and respiratory, blood, and serological specimens for pathogen detection. We compared clinical features of PIV-associated pneumonia among individual serotypes 1, 2, and 3 and among all PIV infections with other viral, atypical, and bacterial pneumonias. We also compared in-hospital disease severity among groups employing an ordinal scale (mild, moderate, severe) using multivariable proportional odds regression.

RESULTS

PIV was more commonly detected in children (155/2354; 6.6%) than in adults (66/2297; 2.9%) (P < .001). Other pathogens were commonly co-detected among PIV cases (110/221; 50%). Clinical features of PIV-1, PIV-2, and PIV-3 infections were similar to one another in both children and adults with pneumonia. In multivariable analysis, children with PIV-associated pneumonia exhibited similar severity to children with other nonbacterial pneumonia, whereas children with bacterial pneumonia exhibited increased severity (odds ratio, 8.42; 95% confidence interval, 1.88-37.80). In adults, PIV-associated pneumonia exhibited similar severity to other pneumonia pathogens.

CONCLUSIONS

Clinical features did not distinguish among infection with individual PIV serotypes in patients hospitalized with community-acquired pneumonia. However, in children, PIV pneumonia was less severe than bacterial pneumonia.

Pneumonia Due to Human Coronavirus OC43 in an Immunocompetent Adult Detected by Multiplex Polymerase Chain Reaction

A 40-year-old woman developed a fever, sore throat, and cough. Coronavirus disease 2019 (COVID-19) was suspected; chest CT showed pan-lobular ground-glass opacity in the bilateral lower lobes suggesting viral pneumonia. Although a reverse transcription loop-mediated isothermal amplification (RT-LAMP) test for COVID-19 using a nasopharyngeal swab was negative, she was hospitalized and isolated because COVID-19 could not be ruled out. After admission, multiplex polymerase chain reaction (PCR) with the FilmArray Respiratory Panel 2.1 from a nasopharyngeal swab was positive for human coronavirus (HCoV) OC43. Therefore, the diagnosis was pneumonia due to HCoV-OC43. Multiplex PCR is useful for differentiating pneumonia due to COVID-19 from that due to other viral pneumonias.

Evaluation of the impact of childhood 13-valent pneumococcal conjugate vaccine introduction on adult pneumonia in Ulaanbaatar, Mongolia: study protocol for an observational study

BACKGROUND

Community-acquired pneumonia is an important cause of morbidity and mortality in adults. Approximately one-third of pneumonia cases can be attributed to the pneumococcus. Pneumococcal conjugate vaccines (PCVs) protect against colonisation with vaccine-type serotypes. The resulting decrease in transmission of vaccine serotypes leads to large indirect effects. There are limited data from developing countries demonstrating the impact of childhood PCV immunisation on adult pneumonia. There are also insufficient data available on the burden and severity of all-cause pneumonia and respiratory syncytial virus (RSV) in adults from low resource countries. There is currently no recommendation for adult pneumococcal vaccination with either pneumococcal polysaccharide vaccine or PCVs in Mongolia. We describe the protocol developed to evaluate the association between childhood 13-valent PCV (PCV13) vaccination and trends in adult pneumonia.

METHODS

PCV13 was introduced into the routine childhood immunisation schedule in Mongolia in a phased manner from 2016. In March 2019 we initiated active hospital-based surveillance for adult pneumonia, with the primary objective of evaluating trends in severe hospitalised clinical pneumonia incidence in adults 18 years and older in four districts of Ulaanbaatar. Secondary objectives include measuring the association between PCV13 introduction and trends in all clinically-defined pneumonia, radiologically-confirmed pneumonia, nasopharyngeal carriage of S. pneumoniae and pneumonia associated with RSV or influenza. Clinical questionnaires, nasopharyngeal swabs, urine samples and chest radiographs were collected from enrolled patients. Retrospective administrative and clinical data were collected for all respiratory disease-related admissions from January 2015 to February 2019.

DISCUSSION

Establishing a robust adult surveillance system may be an important component of monitoring the indirect impact of PCVs within a country. Monitoring indirect impact of childhood PCV13 vaccination on adult pneumonia provides additional data on the full public health impact of the vaccine, which has implications for vaccine efficiency and cost-effectiveness. Adult surveillance in Mongolia will contribute to the limited evidence available on the burden of pneumococcal pneumonia among adults in low- and middle-income countries, particularly in the Asia-Pacific region. In addition, it is one of the few examples of implementing prospective, population-based pneumonia surveillance to evaluate the indirect impact of PCVs in a resource-limited setting.

Clinical phenotypes and outcomes of SARS-CoV-2, influenza, RSV and seven other respiratory viruses: a retrospective study using complete hospital data

Background

An understanding of differences in clinical phenotypes and outcomes COVID-19 compared with other respiratory viral infections is important to optimise the management of patients and plan healthcare. Herein we sought to investigate such differences in patients positive for SARS-CoV-2 compared with influenza, respiratory syncytial virus (RSV) and other respiratory viruses.

Methods

We performed a retrospective cohort study of hospitalised adults and children (≤15 years) who tested positive for SARS-CoV-2, influenza virus A/B, RSV, rhinovirus, enterovirus, parainfluenza viruses, metapneumovirus, seasonal coronaviruses, adenovirus or bocavirus in a respiratory sample at admission between 2011 and 2020.

Results

A total of 6321 adult (1721 SARS-CoV-2) and 6379 paediatric (101 SARS-CoV-2) healthcare episodes were included in the study. In adults, SARS-CoV-2 positivity was independently associated with younger age, male sex, overweight/obesity, diabetes and hypertension, tachypnoea as well as better haemodynamic measurements, white cell count, platelet count and creatinine values. Furthermore, SARS-CoV-2 was associated with higher 30-day mortality as compared with influenza (adjusted HR (aHR) 4.43, 95% CI 3.51 to 5.59), RSV (aHR 3.81, 95% CI 2.72 to 5.34) and other respiratory viruses (aHR 3.46, 95% CI 2.61 to 4.60), as well as higher 90-day mortality, ICU admission, ICU mortality and pulmonary embolism in adults. In children, patients with SARS-CoV-2 were older and had lower prevalence of chronic cardiac and respiratory diseases compared with other viruses.

Conclusions

SARS-CoV-2 is associated with more severe outcomes compared with other respiratory viruses, and although associated with specific patient and clinical characteristics at admission, a substantial overlap precludes discrimination based on these characteristics.

Novel point-of-care biomarker combination tests to differentiate acute bacterial from viral respiratory tract infections to guide antibiotic prescribing: a systematic review

BACKGROUND

Acute respiratory tract infections (RTIs) are the most common reason to seek medical care, with many patients receiving inappropriate antibiotics. Novel testing approaches to identify aetiology at the point-of-care are required to accurately guide antibiotic treatment.

OBJECTIVE

To assess the diagnostic accuracy of biomarker combinations to rapidly differentiate between acute bacterial or viral RTI aetiology.

DATA SOURCES

MEDLINE, Embase and Web of Science databases were searched to February 2021.

STUDY ELIGIBILITY CRITERIA

Diagnostic accuracy studies comparing accuracy of point-of-care and rapid diagnostic tests in primary or secondary care, consisting of biomarker combinations, to identify bacterial or viral aetiology of RTI.

METHODS

Risk of bias was assessed using the QUADAS-2 tool. Sensitivity and specificity of tests reported by more than one study were meta-analysed using a random effects model.

RESULTS

Twenty observational studies (3514 patients) were identified. Eighteen were judged at high risk of bias. For bacterial aetiologies, sensitivity ranged from 61% to 100% and specificity from 18% to 96%. For viral aetiologies, sensitivity ranged from 59% to 97% and specificity from 74% to 100%. Studies evaluating two commercial tests were meta-analysed. For ImmunoXpert, the summary sensitivity and specificity were 85% (95% CI 75%-91%, k = 4) and 86% (95% CI 73%-93%, k = 4) for bacterial infections, and 90% (95% CI 79%-96%, k = 3) and 92% (95% CI 83%-96%, k = 3) for viral infections, respectively. FebriDx had pooled sensitivity and specificity of 84% (95% CI 75%-90%, k = 4) and 93% (95% CI 90%-95%, k = 4) for bacterial infections, and 87% (95% CI 72%-95%; k = 4) and 82% (95% CI 66%-86%, k = 4) for viral infections, respectively.

CONCLUSION

Combinations of biomarkers show potential clinical utility in discriminating the aetiology of RTIs. However, the limitations in the evidence base, due to a high proportion of studies with high risk of bias, preclude firm conclusions. Future research should be in primary care and evaluate patient outcomes and cost-effectiveness with experimental study designs.

CLINICAL TRIAL

PROSPERO registration number: CRD42020178973.

Retrospective study of clinical characteristics and viral etiologies of patients with viral pneumonia in Beijing

Aims

The virus is common in patients with viral pneumonia. However, the viral etiology and clinical features of patients with viral pneumonia in China remain unclear. The main purpose of this study was to analyze the viral causes and epidemiology of patients with viral pneumonia in Beijing, which can significantly improve the pertinence and accuracy of clinical treatment of the disease.

Methods

Firstly, 1539 respiratory specimens of pneumonia (oropharyngeal swabs, nasopharyngeal swabs, saliva samples and bronchoalveolar lavage fluid) were collected from 19 hospitals in Beijing from September 2015 to August 2018. Then, TaqMan low-density microfluidic chip technology was used to detect viral pneumonia specimens in 1539 respiratory tract specimens of pneumonia and determine the types of viral bacteria in them. Lastly, the analysis of demographic, clinical and etiological data of patients with viral pneumonia was performed.

Results

The results showed that among the 1539 respiratory tract specimens with pneumonia, 760 were detected as viral pneumonia specimens, with a positive rate of 49.4%. Among which, 467 were infected with mono-viral and 293 were infected with multi-viral. Influenza A virus (Flu A), mycoplasma pneumoniae (MPn), Ebola virus (EBV) and herpes simplex virus type 1 (HSV-1) were the major viral components in the samples of these patients. Furthermore, these viral species were significantly associated with sample sources, onset season and certain clinical characteristics.

Discussion

Our findings may provide corresponding treatment strategies for viral pneumonia patients infected with specific viruses.

Clinical Features of Human Metapneumovirus-Associated Community-acquired Pneumonia Hospitalizations

BACKGROUND

Human metapneumovirus (HMPV) is a leading cause of respiratory tract infections. Few studies have compared the clinical characteristics and severity of HMPV-associated pneumonia with other pathogens.

METHODS

Active, population-based surveillance was previously conducted for radiographically confirmed, community-acquired pneumonia hospitalizations among children and adults in 8 United States hospitals. Clinical data and specimens for pathogen detection were systematically collected. We described clinical features of all HMPV-associated pneumonia and, after excluding codetections with other pathogen types, we compared features of HMPV-associated pneumonia with other viral, atypical, and bacterial pneumonia and modeled the severity (mild, moderate, and severe) and length of stay using multivariable proportional odds regression.

RESULTS

HMPV was detected in 298/2358 (12.6%) children and 88/2320 (3.8%) adults hospitalized with pneumonia and was commonly codetected with other pathogens (125/298 [42%] children and 21/88 [24%] adults). Fever and cough were the most common presenting symptoms of HMPV-associated pneumonia and were also common symptoms of other pathogens. After excluding codetections in children (n = 1778), compared to HMPV (reference), bacterial pneumonia exhibited increased severity (odds ratio [OR], 3.66; 95% confidence interval [CI], 1.43-9.40), respiratory syncytial virus (RSV; OR, 0.76; 95% CI, .59-.99) and atypical (OR, 0.39; 95% CI, .19-.81) infections exhibited decreased severity, and other viral pneumonia exhibited similar severity (OR, 0.88; 95% CI, .55-1.39). In adults (n = 2145), bacterial (OR, 3.74; 95% CI, 1.87-7.47) and RSV pneumonia (OR, 1.82; 95% CI, 1.32-2.50) were more severe than HMPV (reference), but all other pathogens had similar severity.

CONCLUSIONS

Clinical features did not reliably distinguish HMPV-associated pneumonia from other pathogens. HMPV-associated pneumonia was less severe than bacterial and adult RSV pneumonia, but was otherwise as or more severe than other common pathogens.

Viral community acquired pneumonia at the emergency department: Report from the pre COVID-19 age

The role of viruses in community acquired pneumonia (CAP) has been largely underestimated in the pre‐coronavirus disease 2019 age. However, during flu seasonal early identification of viral infection in CAP is crucial to guide treatment and in‐hospital management. Though recommended, the routine use of nasopharyngeal swab (NPS) to detect viral infection has been poorly scaled‐up, especially in the emergency department (ED). This study sought to assess the prevalence and associated clinical outcomes of viral infections in patients with CAP during peak flu season. In this retrospective, observational study adults presenting at the ED of our hospital (Rome, Italy) with CAP from January 15th to February 22th, 2019 were enrolled. Each patient was tested on admission with Influenza rapid test and real time multiplex assay. Seventy five consecutive patients were enrolled. 30.7% (n = 23) tested positive for viral infection. Of these, 52.1% (n = 12) were H1N1/FluA. 10 patients had multiple virus co‐infections. CAP with viral infection did not differ for any demographic, clinic and laboratory features by the exception of CCI and CURB‐65. All intra‐ED deaths and mechanical ventilations were recorded among CAP with viral infection. Testing only patients with CURB‐65 score ≥2, 10 out of 12 cases of H1N1/FluA would have been detected saving up to 40% tests. Viral infection occurred in one‐third of CAP during flu seasonal peak 2019. Since not otherwise distinguishable, NPS is so far the only reliable mean to identify CAP with viral infection. Testing only patients with moderate/severe CAP significantly minimize the number of tests.

This study stresses the incidence of viral pneumonia during the flu season and underlies the role of viral infection screening at the ED regardless of the current COVID‐19 pandemic.

Clinical Reviews of COVID-19 for Otorhinolaryngologists

The novel SARS-CoV-2 virus that causes COVID-19 has emerged rapidly and the virus has caused a global pandemic since it was first diagnosed in December 2019. SARS-CoV-2 is the seventh virus associated with human transmission among corona viruses. Otorhinolaryngologists could be vulnerable to this viral transmission due to the high viral load in the nasal cavity and nasopharynx. Hence, it is essential to understand the novel COVID-19 from the perspective of otorhinolaryngologists. We provide literature reviews of previous human coronaviruses and the novel COVID-19 with clinical hallmarks, diagnostic approaches, and possible treatment options. Further study is necessary to elucidate viral features and standardize treatment protocols with curable anti-viral agents and vaccines.

Update in Viral Infections in the Intensive Care Unit

The advent of highly sensitive molecular diagnostic techniques has improved our ability to detect viral pathogens leading to severe and often fatal infections that require admission to the Intensive Care Unit (ICU). Viral infections in the ICU have pleomorphic clinical presentations including pneumonia, acute respiratory distress syndrome, respiratory failure, central or peripheral nervous system manifestations, and viral-induced shock. Besides de novo infections, certain viruses fall into latency and can be reactivated in both immunosuppressed and immunocompetent critically ill patients. Depending on the viral strain, transmission occurs either directly through contact with infectious materials and large droplets, or indirectly through suspended air particles (airborne transmission of droplet nuclei). Many viruses can efficiently spread within hospital environment leading to in-hospital outbreaks, sometimes with high rates of mortality and morbidity, thus infection control measures are of paramount importance. Despite the advances in detecting viral pathogens, limited progress has been made in antiviral treatments, contributing to unexpectedly high rates of unfavorable outcomes. Herein, we review the most updated data on epidemiology, common clinical features, diagnosis, pathogenesis, treatment and prevention of severe community- and hospital-acquired viral infections in the ICU settings.

Viral Respiratory Infections: An Ounce of Prevention Is Worth a Pound of Cure

The sudden outbreak and global spread of COVID-19 demanded a tremendous amount of attention for viral respiratory infections (VRIs) in modern times. Evidence accumulated over the past few decades increasingly suggests the importance of recognizing the background and context of lifestyle factors in the prevention of VRIs recurrence. The focus of attention has specifically been on how to optimize respiratory barrier function and immune function during the period of the pandemic outbreak. This viewpoint discusses the impact of a healthy lifestyle on VRIs and demonstrates a practical approach to preventing the occurrence of VRIs based on contemporary evidence.

The effectiveness of vitamin C for patients with severe viral pneumonia in respiratory failure

Background

Vitamin C is a well-known antioxidant and essential cofactor for numerous biological reactions. Several studies reported that vitamin C can improve the symptoms and prognosis of patients with sepsis and respiratory infection. We aimed to examine the effect of vitamin C when used in viral pneumonia patients with severe respiratory failure.

Methods

Total 201 patients with viral pneumonia were included, of them 35 patients used vitamin C. We performed a statistical analysis through a propensity score matching of the age and baseline characteristics of these patients.

Results

There were differences between the vitamin C group and non-vitamin C group in terms of age (60±15 vs. 66±14, P=0.03), extracorporeal membrane oxygenation (28.6% vs. 5.4%, P<0.001), and procalcitonin (3±8 vs. 9±23, P=0.02). The 28-day mortality was not different between the two groups (20.0% vs. 24.7%, P=0.33). In the propensity-matched group, the 28-day mortality was not significantly different between the two groups (20.0% vs. 37.1%, P=0.07). Moreover, no difference was observed in shock reversal within 14 days (45.7% vs. 25.7%, P=0.08) and recovery after acute kidney injury (52.9% vs. 66.7%, P=0.41) between the two groups. Vitamin C was not a prognostic factor for 28-day mortality (P=0.33).

Conclusions

In this study adjunctive intravenous vitamin C therapy alone was not associated with improvement of the 28-day mortality and prognosis in patients with severe viral pneumonia with respiratory failure.

Racial Disparities in Outcomes of Adults Hospitalized for Viral Pneumonia

Background Viral pneumonia is an important cause of respiratory morbidity and mortality. Cases of viral pneumonia are becoming increasingly more common as at-risk populations increase globally. We sought to highlight the racial distribution of hospitalized patients with viral pneumonia and compare their outcomes. Materials and methods Data were obtained from the Nationwide Inpatient Sample (NIS) for 2016 and 2017. The study involved adults who had a principal discharge diagnosis of viral pneumonia. The primary outcome analyzed was inpatient mortality. Secondary outcomes included the development of sepsis, septic shock, acute respiratory failure, acute respiratory distress syndrome, non-ST segment elevation myocardial infarction (NSTEMI), acute kidney failure, deep vein thrombosis, pulmonary embolism, cerebrovascular accident, need for mechanical ventilation, and use of vasopressors as well as mean length of hospitalization and mean total hospital charges. Results Blacks and Hispanics had lower inpatient mortality adjusted odds (aOR: 0.39, 95% CI = 0.229 - 0.662, p<0.001 and aOR: 0.55, 95% CI = 0.347 - 0.858, p=0.009, respectively) compared to Whites. Black and Hispanic patients were also found to have lower adjusted odds ratio of having acute respiratory failure (aOR: 0.54, 95% CI = 0.471 - 0.614, p<0.001, and 0.66, 95% CI = 0.576 - 0.753, p<0.001, respectively). Conclusion Black and Hispanic patients are at lower risk of adverse outcomes when compared to White patients with viral pneumonia.

Detection of Viruses by Multiplex Real-Time Polymerase Chain Reaction in Bronchoalveolar Lavage Fluid of Patients with Nonresponding Community-Acquired Pneumonia

Background

Nonresponding pneumonia is responsible for the most mortality of community-acquired pneumonia (CAP). However, thus far, it is not clear whether viral infection plays an important role in the etiology of nonresponding CAP and whether there is a significant difference in the clinical characteristics between viral and nonviral nonresponding CAP.

Methods

From 2016 to 2019, nonresponding CAP patients were retrospectively enrolled in our study. All patients received bronchoalveolar lavage (BAL) and virus detection in BAL fluid by multiplex real-time polymerase chain reaction (PCR), and clinical, laboratory, and radiographic data were collected.

Results

A total of 43 patients were included. The median age was 62 years, and 65.1% of patients were male. Overall, 20 patients (46.5%) were identified with viral infection. Of these viruses, influenza virus (n = 8) and adenovirus (n = 7) were more frequently detected, and others included herpes simplex virus, human enterovirus, cytomegalovirus, human coronavirus 229E, rhinovirus, and parainfluenza virus. Compared with nonviral nonresponding CAP, only ground-glass opacity combined with consolidation was a more common imaging manifestation in viral nonresponding CAP. However, no obvious differences were found in clinical and laboratory findings between the presence and the absence of viral infections.

Conclusions

Viral infections were particularly frequent in adults with nonresponding CAP. The ground-glass opacity combined with consolidation was a specific imaging manifestation for viral nonresponding CAP, while the clinical and laboratory data showed no obvious differences between viral and nonviral nonresponding CAP.

Comparison of clinical characteristics of patients with pandemic SARS-CoV-2-related and community-acquired pneumonias in Hungary - a pilot historical case-control study

The distinction between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related and community-acquired pneumonias poses significant difficulties, as both frequently involve the elderly. This study aimed to predict the risk of SARS-CoV-2-related pneumonia based on clinical characteristics at hospital presentation. Case-control study of all patients admitted for pneumonia at Semmelweis University Emergency Department. Cases (n = 30) were patients diagnosed with SARS-CoV-2-related pneumonia (based on polymerase chain reaction test) between 26 March 2020 and 30 April 2020; controls (n = 82) were historical pneumonia cases between 1 January 2019 and 30 April 2019. Logistic models were built with SARS-CoV-2 infection as outcome using clinical characteristics at presentation. Patients with SARS-CoV-2-related pneumonia were younger (mean difference, 95% CI: 9.3, 3.2-15.5 years) and had a higher lymphocyte count, lower C-reactive protein, presented more frequently with bilateral infiltrate, less frequently with abdominal pain, diarrhoea, and nausea in age- and sex-adjusted models. A logistic model using age, sex, abdominal pain, C-reactive protein, and the presence of bilateral infiltrate as predictors had an excellent discrimination (AUC 0.88, 95% CI: 0.81-0.96) and calibration (p = 0.27-Hosmer-Lemeshow test). The clinical use of our screening prediction model could improve the discrimination of SARS-CoV-2 related from other community-acquired pneumonias and thus help patient triage based on commonly used diagnostic approaches. However, external validation in independent datasets is required before its clinical use.

Complicating Infections Associated with Common Endemic Human Respiratory Coronaviruses

Coronaviruses OC43, 229E, NL63, and HKU1 are endemic human respiratory coronaviruses that typically cause mild to moderate upper respiratory infections, similar to the common cold. They also may cause simple and complicated lower respiratory infections, otitis media, asthma exacerbations, gastroenteritis, and a few systemic complications. These viruses are usually seasonal (with winter dominance) and affect nearly all age groups. The seasonal and annual variation in virus prevalence has implications for understanding the concept of acquired immunity and its persistence or diminution. Coronaviruses generally have outbreak potential in susceptible populations of any age, particularly in patients with comorbidities, who tend to have increased clinical disease. These 4 coronaviruses are often found in the context of what appears to be coinfection with other pathogens, but especially other viruses. If coronaviruses are not specifically tested for, the sole detection of a viral copathogen would suggest the pathogen is the causative agent, when a coronavirus may be culpable, or both. The detection of these viruses in circumstances where respiratory viruses are generally sought in clinical samples is, therefore, justified. These pathogens can be chronically shed from the respiratory tract, which is more likely to occur among immunocompromised and complicated patients. These viruses share the potential for genetic drift. The genome is among the largest of RNA viruses, and the capability of these viruses to further change is likely underestimated. Given the potential disease among humans, it is justified to search for effective antiviral chemotherapy for these viruses and to consider uses in niche situations should effective therapy be defined. Whereas SARS-CoV-2 may follow the epidemiological pattern of SARS-CoV and extinguish slowly over time, there is yet concern that SARS-CoV-2 may establish itself as an endemic human respiratory coronavirus similar to OC43, 2299E, NL63, and HKU1. Until sufficient data are acquired to better understand the potential of SARS-CoV-2, continued work on antiviral therapy and vaccination is imperative.

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%).

Antibiotic prescription for febrile outpatients: a health facility-based secondary data analysis for the Greater Accra region of Ghana

Background

Misguided prescription of antibiotics is an important contributor towards the emergence and spread of antibiotic resistance. The absence of effective interventions to control antibiotic use leads to increased consumption beyond the needed requirements. Antibiotic stewardship interventions must be appropriately targeted and assessed to enhance the controlled use of antibiotics. The objective of this study was to determine the factors associated with antibiotic prescription to febrile outpatients who seek care in health facilities within the Greater Accra region of Ghana.

Methods

Secondary data obtained from the medical records of 2519 febrile outpatients, consecutively sampled at the outpatient department of 6 health facilities in 3 municipalities during the baseline survey of a quasi-experiment in 2015 was used. The primary outcome was prescription of any antibiotic. Independent variables included patients’ demographics, symptoms, laboratory investigations (blood film microscopy, malaria rapid diagnostic test, full blood count, urine and stool routine examinations), diagnoses, and prescribers’ demographics. Crude and adjusted logistic regression analyses were used to determine the factors associated with antibiotic prescription.

Results

The prevalence of antibiotic prescription was 70.1% (95% CI: 67.7–72.4). Prescribers with more years of practice (> 5 years) were more likely to prescribe antibiotics compared to those with less than 3 years of practice (p <  0.001). Integrated Management of Neonatal and Childhood Illnesses (IMNCI) training was associated with a 2.3 (95% CI: 1.54, 3.53, p <  0.001) fold odds of antibiotic prescribing. Patients aged 5 years or more were 60% less likely to receive antibiotics compared with those under 5 years (AOR = 0.40, 95% CI: 0.32, 0.51; p <  0.001). Patients referred for laboratory investigations were 29% less likely to be prescribed antibiotics than those not referred. The presence of cough as a presenting symptom was associated with a 3.5 (95% CI: 2.54, 4.92) fold odds of antibiotic prescription.

Conclusion

Prescription of antibiotics to febrile outpatients was high. Promoting laboratory testing can potentially reduce irrational antibiotic prescription. Prescribing antibiotics for children under five and the prescribing practices of prescribers with longer years of practice should be targeted with interventions to reduce high use of antibiotics.

The epidemiology and estimated etiology of pathogens detected from the upper respiratory tract of adults with severe acute respiratory infections in multiple countries, 2014-2015

INTRODUCTION

Etiology studies of severe acute respiratory infections (SARI) in adults are limited. We studied potential etiologies of SARI among adults in six countries using multi-pathogen diagnostics.

METHODS

We enrolled both adults with SARI (acute respiratory illness onset with fever and cough requiring hospitalization) and asymptomatic adults (adults hospitalized with non-infectious illnesses, non-household members accompanying SARI patients, adults enrolled from outpatient departments, and community members) in each country. Demographics, clinical data, and nasopharyngeal and oropharyngeal specimens were collected from both SARI patients and asymptomatic adults. Specimens were tested for presence of 29 pathogens utilizing the Taqman® Array Card platform. We applied a non-parametric Bayesian regression extension of a partially latent class model approach to estimate proportions of SARI caused by specific pathogens.

RESULTS

We enrolled 2,388 SARI patients and 1,135 asymptomatic adults from October 2013 through October 2015. We detected ≥1 pathogen in 76% of SARI patients and 67% of asymptomatic adults. Haemophilus influenzae and Streptococcus pneumoniae were most commonly detected (≥23% of SARI patients and asymptomatic adults). Through modeling, etiology was attributed to a pathogen in most SARI patients (range among countries: 57.3-93.2%); pathogens commonly attributed to SARI etiology included influenza A (14.4-54.4%), influenza B (1.9-19.1%), rhino/enterovirus (1.8-42.6%), and RSV (3.6-14.6%).

CONCLUSIONS

Use of multi-pathogen diagnostics and modeling enabled attribution of etiology in most adult SARI patients, despite frequent detection of multiple pathogens in the upper respiratory tract. Seasonal flu vaccination and development of RSV vaccine would likely reduce the burden of SARI in these populations.

Impact of Influenza on Pneumococcal Vaccine Effectiveness during Streptococcus pneumoniae Infection in Aged Murine Lung

Changes in innate and adaptive immune responses caused by viral imprinting can have a significant direct or indirect influence on secondary infections and vaccine responses. The purpose of our current study was to investigate the role of immune imprinting by influenza on pneumococcal vaccine effectiveness during Streptococcus pneumoniae infection in the aged murine lung. Aged adult (18 months) mice were vaccinated with the pneumococcal polyvalent vaccine Pneumovax (5 mg/mouse). Fourteen days post vaccination, mice were instilled with PBS or influenza A/PR8/34 virus (3.5 × 10² PFU). Control and influenza-infected mice were instilled with PBS or S. pneumoniae (1 × 10³ CFU, ATCC 6303) on day 7 of infection and antibacterial immune responses were assessed in the lung. Our results illustrate that, in response to a primary influenza infection, there was diminished bacterial clearance and heightened production of pro-inflammatory cytokines, such as IL6 and IL1β. Vaccination with Pneumovax decreased pro-inflammatory cytokine production by modulating NFҡB expression; however, these responses were significantly diminished after influenza infection. Taken together, the data in our current study illustrate that immune imprinting by influenza diminishes pneumococcal vaccine efficacy and, thereby, may contribute to increased susceptibility of older persons to a secondary infection with S. pneumoniae.

The Clinical Presentation and Immunology of Viral Pneumonia and Implications for Management of Coronavirus Disease 2019

This review will briefly examine the clinical presentation and important immunology of viral pneumonia with a focus on severe acute respiratory syndrome coronavirus 2 (coronavirus disease 2019).

Severity of coronavirus respiratory tract infections in adults admitted to acute care in Toronto, Ontario

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Coronaviruses represent a significant burden in acute care settings.

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Female gender and smoking were associated with poor prognosis.

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All cause mortality in our cohort was similar to what is observed for influenza virus.

Background

The World Health Organization has highlighted the need for improved surveillance and understanding of the health burden imposed by non-influenza RNA respiratory viruses. Human coronaviruses (CoVs) are a major cause of respiratory and gastrointestinal tract infections with associated morbidity and mortality.

Objectives

The objective of our study was to characterize the epidemiology of CoVs in our tertiary care centre, and identify clinical correlates of disease severity.

Study design

A cross-sectional study was performed of 226 patients admitted with confirmed CoV respiratory tract infection between 2010 and 2016. Variables consistent with a severe disease burden were evaluated including symptoms, length of stay, intensive care unit (ICU) admission and mortality.

Results

CoVs represented 11.3% of all positive respiratory virus samples and OC43 was the most commonly identified CoV. The majority of infections were community-associated while 21.6% were considered nosocomial. The average length of stay was 11.8 days with 17.3% of patients requiring ICU admission and an all-cause mortality of 7%. In a multivariate model, female gender and smoking were associated with increased likelihood of admission to ICU or death.

Conclusion

This study highlights the significant burden of CoVs and justifies the need for surveillance in the acute care setting.

The burden of respiratory syncytial virus in adults: a systematic review and meta-analysis

Respiratory syncytial virus (RSV) is the most common pathogen associated with acute lower respiratory tract infections in young children. RSV is also a major viral pathogen causing severe lung disease in the adult population, particularly among the elderly. We conducted a review of adult RSV studies published from January 1970 to February 2017 to determine the burden of disease among adults worldwide. There were no restrictions on health care setting or definition of RSV infection. A total of 1530 published studies were identified, 95 of which were included in this review. The incidence rates of hospitalised RSV acute respiratory tract infection (ARI) in adults >65 years old ranged from 7.3 to 13.0/10⁵ population in Africa and Asia and from 190 to 254/10⁵ population in the USA. Higher incidence rates (195–1790/10⁵ population) were observed in adults ≥50 years old for outpatient or emergency visits in the USA. Of all ARI patients, RSV accounted for 1–10% in adults and 2–14% in patients with chronic diseases or transplantation. Given the limitations in the existing data, significant efforts should be made to generate evidence on the burden of RSV infections in adults and to estimate the potential impact of future preventive interventions.

Parainfluenza Virus in Hospitalized Adults: A 7-Year Retrospective Study

Background

Parainfluenza virus (PIV) is a cause of respiratory tract infection in children and the immunocompromised population, but its clinical manifestations, impact, and outcomes in hospitalized adults are not well studied.

Methods

This retrospective study included adults (≥18 years old) admitted to Northwestern Memorial Hospital or Prentice Women's Hospital (both in Chicago, Illinois) between 1 August 2009 and 31 July 2016 with a positive molecular test result for PIV. Epidemiologic, clinical, and outcomes data were collected from the enterprise data warehouse and patient electronic health records after institutional review board approval. Descriptive statistics were used to summarize the data.

Results

A total of 550 adults with a positive molecular test for PIV were identified. Differences in seasonality, clinical presentation, and prevalence between the different PIV serotypes (PIV-1, PIV-2, and PIV-3) were identified. The most common signs/symptoms were cough (88%), productive sputum (55%), fever (63%), and dyspnea (49%). Of the patients administered antibiotics, 349 (79.6%) had no confirmed bacterial infection throughout their hospitalization. The average length of hospitalization was 7.7 days. Presence of bacterial coinfection (P = .01), fungal coinfection (P < .01), decreased body mass index (P = .03), and increased respiratory rate (P < .01) were associated with significant differences in mortality rates.

Conclusions

PIV infection is associated with substantial morbidity in hospitalized adults. Such data will be useful in understanding the impact on epidemiology and outcomes if a PIV-specific vaccine becomes available. Furthermore, this highlights the need for novel preventive and therapeutic approaches to PIV infection.

Systematic review on respiratory syncytial virus epidemiology in adults and the elderly in Latin America

OBJECTIVES

The present study provides a comprehensive review of the recently published data on RSV epidemiology in adults and the elderly in Latin America.

METHODS

A systematic literature search was carried out in Medline, Scielo, Lilacs, and Cochrane Library. The search strategy aimed at retrieving studies focusing on RSV prevalence, burden, risk factors, and the routine clinical practice in the prevention and management of RSV infections in Latin American countries. Only articles published between January 2011 and December 2017 were considered.

RESULTS

Eighteen studies were included. Percentages of RSV detection varied highly across included studies for adult subjects with respiratory infections (0% to 77.9%), influenza-like illness (1.0% to 16.4%) and community-acquired pneumonia (1.3% to 13.5%). Considerable percentages of hospitalization were reported for RSV-infected adults with influenza-like illness (40.9% and 69.9%) and community-acquired pneumonia (91.7%).

CONCLUSIONS

Recent RSV data regarding adult populations in Latin America are scarce. RSV was documented as a cause of illness in adults and the elderly, being identified in patients with acute respiratory infections, influenza-like illness and community-acquired pneumonia. The studies suggest that RSV infections may be a significant cause of hospitalization in adult populations in Latin America, including younger adults.

Bilateral massive pneumonia as an unusual manifestation of Puumala hantavirus infection

Renal involvement due to European Puumala virus (PUUV) is frequent but pulmonary involvement is quite rare. We present here, a 24-year-old male with atypical clinical presentation of acute PUUV infection with gross pulmonary and minimal renal involvement. Severe pulmonary manifestations of PUUV infection, in this case, highlights that hantavirus infection should be considered in the differential diagnosis of atypical pneumonia.

Two cases of primary human parechovirus pneumonia in adults

Human parechoviruses (HPeV) are mainly isolated from upper respiratory tract infection and gastroenteritis in children. HPeV has not been screened for in the past studies of community-acquired pneumonia (CAP) in adults, and its association with CAP is unknown. We present two cases that HPeV was detected by multiplex polymerase chain reaction for respiratory viruses using bronchoalveolar lavage fluid and diagnosed as pneumonia caused by HPeV.

Influenza Infections and Emergent Viral Infections in Intensive Care Unit

Critically ill patients are admitted to an intensive care unit (ICU) for multiple reasons. In this study, we aim to analyze the current evidence and findings associated with influenza and other emergent viral infections, namely, herpes simplex virus type 1 (HSV-1), Epstein-Barr virus (EBV), and cytomegalovirus (CMV).

Among medical conditions, community-acquired respiratory infections are the most frequent reason for ventilatory support in ICUs. Community-acquired pneumonia in a severe form including the need of invasive mechanical ventilation and/or vasopressors is associated with high mortality rates. However, after the pandemic that occurred in 2009 by H1N1 influenza, the number of cases being admitted to ICUs with viral infections is on the rise. Patients in whom an etiology would not have been identified in the past are currently being tested with more sensitive viral molecular diagnostic tools, and patients being admitted to ICUs have more preexisting medical conditions that can predispose to viral infections. Viral infections can trigger the dysregulation of the immune system by inducing a massive cytokine response. This cytokine storm can cause endothelial damage and dysfunction, deregulation of coagulation, and, consequently, alteration of microvascular permeability, tissue edema, and shock. In severe influenza, this vascular hyperpermeability can lead to acute lung injury, multiorgan failure, and encephalopathy. In immunocompetent patients, the most common viral infections are respiratory, and influenza should be considered in patients with severe respiratory failure being admitted to ICU. Seasonality and coinfection are two important features when considering influenza as a pathogen in critically ill patients.

Herpesviridae (HSV, CMV, and EBV) may reactivate in ICU patients, and their reactivation is associated with morbidity/mortality. However, whether a specific treatment may impact on outcome remains to be determined.

Impact of multiplex respiratory virus testing on antimicrobial consumption in adults in acute care: a randomized clinical trial

Objectives

Inappropriate use of antibiotics is associated with development of antimicrobial resistance. In respiratory infections it is often difficult to differentiate between viral and bacterial infections, and empirical treatment is common. Enhanced viral testing is expected to clarify clinical decision-making and reduce the prescription of antibacterial agents, but the impact of such information on patient care is unclear.

Methods

We conducted a (1:1) randomized controlled clinical trial involving 998 adults with respiratory symptoms, fever, chest pain or poor general condition in the emergency unit of a tertiary hospital. Multiplex PCR results for 496 patients were available in 24 hours (intervention group) and those for the remaining 502 patients were available in 7 days (control group). Our primary outcome measures were the duration of hospitalization and the consumption of antibiotics within 30 days of enrolment.

Results

In all, 841 of 998 (84%) patients had respiratory symptoms at study entry. A respiratory virus was detected in 175 (17.5%). The mean duration of hospitalization was 4.2 days (SD 5.4) in the intervention group and 4.1 days (SD 4.9) in the control group (difference 0.1, 95% CI –0.5 to 0.6, p 0.810). The mean days on antibiotics were 11.3 days (SD 12.6) in the intervention group and 10.4 days (SD 11.4) in the control group (difference 0.9, 95% CI –0.6 to 2.4, p 0.235).

Conclusions

Multiplex PCR testing for respiratory viruses with results available within 24 hours did not reduce the consumption of bacterial antibiotics or the length of hospital stay in adults presenting with respiratory symptoms, fever, chest pain or reduced general condition in acute care.

Community-acquired Pneumonia and Hospital-acquired Pneumonia

Pneumonia is among the leading causes of morbidity and mortality worldwide. Although Streptococcus pneumoniae is the most likely cause in most cases, the variety of potential pathogens can make choosing a management strategy a complex endeavor. The setting in which pneumonia is acquired heavily influences diagnostic and therapeutic choices. Because the causative organism is typically unknown early on, timely administration of empiric antibiotics is a cornerstone of pneumonia management. Disease severity and rates of antibiotic resistance should be carefully considered when choosing an empiric regimen. When complications arise, further work-up and consultation with a pulmonary specialist may be necessary.

Epidemiology and outcomes of hospitalized adults with respiratory syncytial virus: A 6-year retrospective study

Objectives

Respiratory syncytial virus (RSV) is an important cause of morbidity and mortality in adults. Existing studies are limited by the number of seasons studied and most have focused on the immunocompromised.

Methods

A retrospective cohort study was conducted on all adults (≥18 years) with a positive RSV molecular test admitted from 2009 to 2015 to one hospital in Chicago, IL. Epidemiologic and outcomes data were collected after IRB approval.

Results

Of the 489 eligible patients, 227 had RSV A and 262 had RSV B. Patients had a median age of 61 years and comorbidity (eg, chronic lung disease [40.6%], obesity [37.8%], and cardiac disease [34.3%]). On presentation, most had cough (86.5%), fever (42.4%), and shortness of breath (38.2%). Severe disease was present in 27.6% of patients. Antibiotic was used in 76.3% inpatients and 45.8% at discharged despite few patients (4.7%) having documented bacterial infections. Supplemental oxygen and mechanical ventilation were utilized in 44.6% and 12.3%, respectively, while ICU level care was required in 26.9%. Most patients were discharged home (82.7%). Most deaths (68.4%, 13/19) were attributed to pneumonia or hypoxemia likely from RSV. Most fatal cases were seen in those with recent cancer treatment and older adults.

Conclusions

Respiratory syncytial virus in hospitalized adults is associated with significant morbidity and mortality with 26.9% requiring ICU level care. Antibiotics are commonly prescribed to patients with documented RSV, and antibiotics are frequently continued after diagnosis. Novel antiviral therapies are needed for RSV to improve outcomes and potentially improve antibiotic stewardship in patients without a bacterial infection.

Pneumonia severity index in viral community acquired pneumonia in adults

Pneumonia severity index (PSI) is an important scoring system that can assess the severity of community acquired pneumonia and determine admission status. However, there is a lack of research on whether this scoring system can be applied to viral community acquired pneumonia. The purpose of this study was to evaluate the usefulness of PSI in viral community acquired pneumonia. This retrospective cohort study included 1,434 adult patients (aged ≥18 years) who were admitted to the emergency department of a university hospital during 2013–2015 because of community-acquired pneumonia. Viral infections were diagnosed by multiplex PCR. Patients diagnosed with non-viral community-acquired pneumonia were included in the control group (N = 1,173). The main outcome was 30-day all-cause mortality. multivariate Cox regression analyses were performed to calculate the risk of death. Respiratory viruses were detected in 261 (18.2%) patients with community-acquired pneumonia. Two types of respiratory viruses were detected in 7 cases. Of the 254 cases detected with only one virus, 62 were influenza A, 18 were influenza B, 65 were rhinovirus, 35 were respiratory syncytial virus, 25 were metapneumovirus, 20 were parainfluenza, 17 were coronavirus, 7 were bocavirus, and 5 were adenovirus. Mortality was not significantly different between patients with respiratory virus and those without respiratory virus; the 30-day all-cause mortality rates were 20.3% and 22.4%, respectively (P = 0.45). Mortality rate increased with an increasing PSI score with or without respiratory viral infection. Pulmonary severity index was significantly associated with mortality adjusted for respiratory virus detection (hazard ratio = 1.024, 95% confidence interval = 1.020–1.028). Pneumonia severity index score is an important factor for assessing the prognosis of patients with community-acquired pneumonia, regardless of respiratory virus detection.

Differential Diagnosis of Asthma

Asthma is one of the most common chronic syndromes worldwide (Moorman et al., Vital Health Stat 3(35), 2012). It is not a diagnosis but a clinical syndrome based on a constellation of signs and symptoms (Li et al., Ann Allergy Asthma Immunol 81:415–420(IIa), 1998). The classic symptoms of asthma include chest tightness, wheeze, cough, and dyspnea (Moorman et al., Vital Health Stat 3(35), 2012). The term asthma encompasses a spectrum of pulmonary diseases sharing the hallmark of reversible airway obstruction and can be classified as allergic or non-allergic (Löwhagen, J Asthma. 52(6):538–44, 2015). Asthma designated allergic is due to an immunoglobulin E (IgE)-mediated process, but as noted not all asthma is allergic in etiology (Romanet-Manent et al., Allergy 57:607–13, 2002). The differential diagnosis for asthma is broad and requires a detailed history with supportive pulmonary function tests to be properly diagnosed.

An international perspective on hospitalized patients with viral community-acquired pneumonia

BACKGROUND

Who should be tested for viruses in patients with community acquired pneumonia (CAP), prevalence and risk factors for viral CAP are still debated. We evaluated the frequency of viral testing, virus prevalence, risk factors and treatment coverage with oseltamivir in patients admitted for CAP.

METHODS

Secondary analysis of GLIMP, an international, multicenter, point-prevalence study of hospitalized adults with CAP. Testing frequency, prevalence of viral CAP and treatment with oseltamivir were assessed among patients who underwent a viral swab. Univariate and multivariate analysis was used to evaluate risk factors.

RESULTS

553 (14.9%) patients with CAP underwent nasal swab. Viral CAP was diagnosed in 157 (28.4%) patients. Influenza virus was isolated in 80.9% of cases. Testing frequency and viral CAP prevalence were inhomogeneous across the participating centers. Obesity (OR 1.59, 95%CI: 1.01-2.48; p = 0.043) and need for invasive mechanical ventilation (OR 1.62, 95%CI: 1.02-2.56; p = 0.040) were independently associated with viral CAP. Prevalence of empirical treatment with oseltamivir was 5.1%.

CONCLUSION

In an international scenario, testing frequency for viruses in CAP is very low. The most common cause of viral CAP is Influenza virus. Obesity and need for invasive ventilation represent independent risk factors for viral CAP. Adherence to recommendations for treatment with oseltamivir is poor.