Laboratory-confirmed Respiratory Virus Infection Research Articles

Prolonged lymphopenia and prognoses among inpatients with different respiratory virus infections: A retrospective cohort study

BackgroundLymphopenia is common in respiratory viral infection. However, no studies elucidated the impact of prolonged lymphopenia on worse outcome in the way of quantitative risk. MethodsAdult patients with laboratory-confirmed respiratory virus infection (influenza, SARS-CoV-2, and other viruses) between January 1st, 2016, and February 1st, 2023 were enrolled in this retrospective cohort study. Serial data of laboratory examination during hospitalization were acquired. The primary outcome was in-hospital all-cause death, and all information was obtained from the electronic medical records system. Legendre orthogonal polynomials (LOP), restricted cubic splines, and multivariable logistic regression were performed. ResultsFinally, 2388 inpatients were involved in this study, including 436 patients with influenza, 1397 with SARS-CoV-2, and 319 with other respiratory virus infections. After being adjusted for age, corticosteroids, chronic kidney disease, chronic respiratory disease, cardiovascular disease, lymphopenia on admission and length of hospital stay, prolonged lymphopenia was significantly associated with death in influenza (OR 7.20, 95 % CI 2.27–22.77, p = 0. 0008 for lasting for 3–7 days; OR 17.80, 95 % CI 5.21–60.82, p < 0.0001 for lasting for more than 7 days) and SARS-CoV-2 (OR 3.07, 95 % CI 1.89–5.01, p < 0.0001 for lasting for 3–7 days; OR 6.28, 95 % CI 3.53–11.18, p < 0.0001 for lasting for more than 7 days), compared with a transient lymphopenia of 1–2 days, while no significant association was found in other respiratory viruses. Prolonged lymphopenia was also associated with multi-organ damage in influenza and SARS-CoV-2 infections. ConclusionsProlonged lymphopenia was significantly associated with worse clinical prognoses in influenza and SARS-CoV-2 infections, but not in other respiratory virus infections.

A meta-analysis evaluating the effect of N95 respirators in healthcare and non-healthcare providers on laboratory-confirmed respiratory virus infection

A meta-analysis evaluating the effect of N95 respirators in healthcare and non-healthcare providers on laboratory-confirmed respiratory virus infection

Protective efficient comparisons among all kinds of respirators and masks for health-care workers against respiratory viruses: A PRISMA-compliant network meta-analysis.

Background:There is no definite conclusion about comparison of better effectiveness between N95 respirators and medical masks in preventing health-care workers (HCWs) from respiratory infectious diseases, so that conflicting results and recommendations regarding the protective effects may cause difficulties for selection and compliance of respiratory personal protective equipment use for HCWs, especially facing with pandemics of corona virus disease 2019.Methods:We systematically searched MEDLINE, Embase, PubMed, China National Knowledge Infrastructure, Wanfang, medRxiv, and Google Scholar from initiation to November 10, 2020 for randomized controlled trials, case-control studies, cohort studies, and cross-sectional studies that reported protective effects of masks or respirators for HCWs against respiratory infectious diseases. We gathered data and pooled differences in protective effects according to different types of masks, pathogens, occupations, concurrent measures, and clinical settings. The study protocol is registered with PROSPERO (registration number: 42020173279).Results:We identified 4165 articles, reviewed the full text of 66 articles selected by abstracts. Six randomized clinical trials and 26 observational studies were included finally. By 2 separate conventional meta-analyses of randomized clinical trials of common respiratory viruses and observational studies of pandemic H1N1, pooled effects show no significant difference between N95 respirators and medical masks against common respiratory viruses for laboratory-confirmed respiratory virus infection (risk ratio 0.99, 95% confidence interval [CI] 0.86–1.13, I2 = 0.0%), clinical respiratory illness (risk ratio 0.89, 95% CI 0.45–1.09, I2 = 83.7%, P = .002), influenza-like illness (risk ratio 0.75, 95% CI 0.54–1.05, I2 = 0.0%), and pandemic H1N1 for laboratory-confirmed respiratory virus infection (odds ratio 0.92, 95% CI 0.49–1.70, I2 = 0.0%, P = .967). But by network meta-analysis, N95 respirators has a significantly stronger protection for HCWs from betacoronaviruses of severe acute respiratory syndrome, middle east respiratory syndrome, and corona virus disease 2019 (odds ratio 0.43, 95% CI 0.20–0.94).Conclusions:Our results provide moderate and very-low quality evidence of no significant difference between N95 respirators and medical masks for common respiratory viruses and pandemic H1N1, respectively. And we found low quality evidence that N95 respirators had a stronger protective effectiveness for HCWs against betacoronaviruses causative diseases compared to medical masks. The evidence of comparison between N95 respirators and medical masks for corona virus disease 2019 is open to question and needs further study.

Influenza and other respiratory viral infections associated with absence from school among schoolchildren in Pittsburgh, Pennsylvania, USA: a cohort study

BackgroundInformation on the etiology and age-specific burden of respiratory viral infections among school-aged children remains limited. Though school aged children are often recognized as driving the transmission of influenza as well as other respiratory viruses, little detailed information is available on the distribution of respiratory infections among children of different ages within this group. Factors other than age including gender and time spent in school may also be important in determining risk of infection but have been little studied in this age group.MethodsWe conducted a cohort study to determine the etiology of influenza like illness (ILI) among 2519 K–12 students during the 2012–13 influenza season. We obtained nasal swabs from students with ILI-related absences. Generalized linear mixed-effect regressions determined associations of outcomes, including ILI and laboratory-confirmed respiratory virus infection, with school grade and other covariates.ResultsOverall, 459 swabs were obtained from 552 ILI–related absences. Respiratory viruses were found in 292 (63.6%) samples. Influenza was found in 189 (41.2%) samples. With influenza B found in 134 (70.9%). Rates of influenza B were significantly higher in grades 1 (10.1, 95% CI 6.8–14.4%), 2 (9.7, 6.6–13.6%), 3 (9.3, 6.3–13.2%), and 4 (9.9, 6.8–13.8%) than in kindergarteners (3.2, 1.5–6.0%). After accounting for grade, sex and self-reported vaccination status, influenza B infection risk was lower among kindergarteners in half-day programs compared to kindergarteners in full-day programs (OR = 0.19; 95% CI 0.08–0.45).ConclusionsILI and influenza infection is concentrated in younger schoolchildren. Reduced infection by respiratory viruses is associated with a truncated school day for kindergarteners but this finding requires further investigation in other grades and populations.

A cluster randomized clinical trial comparing fit-tested and non-fit-tested N95 respirators to medical masks to prevent respiratory virus infection in health care workers

Please cite this paper as: MacIntyre et al. (2011) A cluster randomized clinical trial comparing fit‐tested and non‐fit‐tested N95 respirators to medical masks to prevent respiratory virus infection in health care workers. Influenza and Other Respiratory Viruses DOI: 10.1111/j.1750‐2659.2010.00198.x. Background We compared the efficacy of medical masks, N95 respirators (fit tested and non fit tested), in health care workers (HCWs). Methods A cluster randomized clinical trial (RCT) of 1441 HCWs in 15 Beijing hospitals was performed during the 2008/2009 winter. Participants wore masks or respirators during the entire work shift for 4 weeks. Outcomes included clinical respiratory illness (CRI), influenza‐like illness (ILI), laboratory‐confirmed respiratory virus infection and influenza. A convenience no‐mask/respirator group of 481 health workers from nine hospitals was compared. Findings The rates of CRI (3·9% versus 6·7%), ILI (0·3% versus 0·6%), laboratory‐confirmed respiratory virus (1·4% versus 2·6%) and influenza (0·3% versus 1%) infection were consistently lower for the N95 group compared to medical masks. By intention‐to‐treat analysis, when P values were adjusted for clustering, non‐fit‐tested N95 respirators were significantly more protective than medical masks against CRI, but no other outcomes were significant. The rates of all outcomes were higher in the convenience no‐mask group compared to the intervention arms. There was no significant difference in outcomes between the N95 arms with and without fit testing. Rates of fit test failure were low. In a post hoc analysis adjusted for potential confounders, N95 masks and hospital level were significant, but medical masks, vaccination, handwashing and high‐risk procedures were not. Interpretation Rates of infection in the medical mask group were double that in the N95 group. A benefit of respirators is suggested but would need to be confirmed by a larger trial, as this study may have been underpowered. The finding on fit testing is specific to the type of respirator used in the study and cannot be generalized to other respirators. Trial registration Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN: ACTRN12609000257268 (http://www.anzctr.org.au).