Epidemiology of Hospital Admissions with Influenza during the 2013/2014 Northern Hemisphere Influenza Season: Results from the Global Influenza Hospital Surveillance Network
Open Access
- 19 May 2016
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 11 (5), e0154970
- https://doi.org/10.1371/journal.pone.0154970
Abstract
The Global Influenza Hospital Surveillance Network was established in 2012 to obtain valid epidemiologic data on hospital admissions with influenza-like illness. Here we describe the epidemiology of admissions with influenza within the Northern Hemisphere sites during the 2013/2014 influenza season, identify risk factors for severe outcomes and complications, and assess the impact of different influenza viruses on clinically relevant outcomes in at-risk populations. Eligible consecutive admissions were screened for inclusion at 19 hospitals in Russia, Turkey, China, and Spain using a prospective, active surveillance approach. Patients that fulfilled a common case definition were enrolled and epidemiological data were collected. Risk factors for hospitalization with laboratory-confirmed influenza were identified by multivariable logistic regression. 5303 of 9507 consecutive admissions were included in the analysis. Of these, 1086 were influenza positive (534 A(H3N2), 362 A(H1N1), 130 B/Yamagata lineage, 3 B/Victoria lineage, 40 untyped A, and 18 untyped B). The risk of hospitalization with influenza (adjusted odds ratio [95% confidence interval]) was elevated for patients with cardiovascular disease (1.63 [1.33–2.02]), asthma (2.25 [1.67–3.03]), immunosuppression (2.25 [1.23–4.11]), renal disease (2.11 [1.48–3.01]), liver disease (1.94 [1.18–3.19], autoimmune disease (2.97 [1.58–5.59]), and pregnancy (3.84 [2.48–5.94]). Patients without comorbidities accounted for 60% of admissions with influenza. The need for intensive care or in-hospital death was not significantly different between patients with or without influenza. Influenza vaccination was associated with a lower risk of confirmed influenza (adjusted odds ratio = 0.61 [0.48–0.77]). Influenza infection was detected among hospital admissions with and without known risk factors. Pregnancy and underlying comorbidity increased the risk of detecting influenza virus in patients hospitalized with influenza-like illness. Our results support influenza vaccination as a measure for reducing the risk of influenza-associated hospital admission.This publication has 43 references indexed in Scilit:
- Influenza Vaccine Effectiveness against Hospitalisation with Confirmed Influenza in the 2010–11 Seasons: A Test-negative Observational StudyPLOS ONE, 2013
- Hospitalizations Associated With Influenza and Respiratory Syncytial Virus in the United States, 1993–2008Clinical Infectious Diseases, 2012
- Seasonal and pandemic influenza surveillance considerations for constructing multicomponent systemsInfluenza and Other Respiratory Viruses, 2009
- The Influenza Virus EnigmaCell, 2009
- Optimal Sampling Sites and Methods for Detection of Pathogens Possibly Causing Community-Acquired Lower Respiratory Tract InfectionsJournal of Clinical Microbiology, 2009
- Indicators of socioeconomic position (part 2)Journal of Epidemiology and Community Health, 2006
- Indicators of socioeconomic position (part 1)Journal of Epidemiology and Community Health, 2006
- Measuring inconsistency in meta-analysesBMJ, 2003
- Nasal Swab versus Nasopharyngeal Aspirate for Isolation of Respiratory VirusesJournal of Clinical Microbiology, 2002
- Quantifying heterogeneity in a meta-analysisStatistics in Medicine, 2002