Abstract
BackgroundEstimates of influenza and respiratory syncytial virus (RSV) burden must be periodically updated to inform public health strategies. We estimated seasonal influenza- and RSV-attributable hospitalizations in the US from 1997 to 2009 according to age and risk status (NCT01599390).MethodsMultiple linear regression modelling was used to attribute hospitalizations to influenza or RSV using virological surveillance and hospitalization data. Hospitalization data were obtained from the US Nationwide Inpatient Sample and virology data were obtained from FluView (Centers for Disease Control and Prevention). Outcomes included any mention of ICD-coded respiratory disease and cardiorespiratory disease diagnoses. We also explored a broader definition of respiratory disease that included mention of relevant respiratory sign/symptoms and viral infection (“respiratory broad”).ResultsApplying the respiratory broad outcome, our model attributed ~300,000 and ~200,000 hospitalizations to influenza and RSV, respectively. Influenza A/H3N2 was the predominant cause of influenza-related hospitalizations in most seasons, except in three seasons when influenza B was dominant; likewise, A/H3N2 caused most influenza-related hospitalizations in all age segments, except in children <18 years where the relative contribution of A/H3N2 and B was similar. Most influenza A- and B-related hospitalizations occurred in seniors while approximately one half and one third of all RSV-related events occurred in children 0–4 years and seniors 65+ years, respectively. High-risk status was associated with higher risk of both influenza- and RSV-attributable hospitalizations in adults, but not in children.ConclusionsOur study assessed the burden of influenza and RSV, information that is important for both cost effectiveness studies and for prioritization of the development of antivirals and vaccines. For seniors, we found that the burdens of influenza and RSV were both substantial. Among children <18 years, about half of all influenza hospitalizations were due to influenza B, most occurring in children without noted risk conditions. RSV hospitalizations among children were confined to those 0–4 years. Our study also demonstrated the importance of the outcome used to estimate hospitalization burden. Our findings highlight the burden of influenza among children regardless of risk status and underscore the prevalence of RSV infections among both young children and older adults.
Highlights
Estimates of influenza and respiratory syncytial virus (RSV) burden must be periodically updated to inform public health strategies
Estimates of hospitalization burden using various outcomes Outcomes with the relevant International Classification of Disease (ICD) codes among any of the discharge diagnoses (“any mention”) Over the 12 winter seasons during 1997–2009, the model estimated an average seasonal burden of 297,548 influenza-attributable hospitalizations when applied to time series using the respiratory broad outcome; this is equivalent to a mean annual rate of 102 per 100,000 population (Table 2)
It is more likely that co-circulating strains could result in a reduction of the burden due to cross-protection [39], competitive exclusion or both. This makes the additive model more plausible from a biological and epidemiological perspective [38,39,40]. This is the first study to model estimates of influenzaand RSV-attributable hospitalizations in the US according to a novel outcome, and to use expanded age groups and risk based status across all age groups
Summary
Estimates of influenza and respiratory syncytial virus (RSV) burden must be periodically updated to inform public health strategies. We estimated seasonal influenza- and RSV-attributable hospitalizations in the US from 1997 to 2009 according to age and risk status (NCT01599390). Viral respiratory illnesses such as influenza and respiratory syncytial virus (RSV) impose a substantial burden of hospitalization [1,2,3,4,5]. Influenza has a disproportionate impact on the young, older adults, and persons with underlying high risk medical conditions [1, 2]. Clinical manifestations of RSV infection range from sinusitis and otitis media to bronchiolitis and pneumonia
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
