Prevalence and contribution of respiratory viruses in the community to rates of emergency department visits and hospitalizations with respiratory tract infections, chronic obstructive pulmonary disease and asthma.

BACKGROUND

The individual and combined contribution of viral prevalence in the community to Emergency Department (ED) visits and hospitalizations with respiratory tract infections (RTIs), chronic obstructive pulmonary disease (COPD) and asthma is unclear.

METHODS

A retrospective analysis on daily viral positive tests and daily ED visits and hospitalizations between 01/01/2003 to 31/12/2013 in Ontario, Canada. Viral data was collected from the Centre for Immunization and Respiratory Infectious Diseases (CIRID). The Canadian Institute for Health Information reports daily ED visits and hospitalizations for RTIs, COPD and asthma as a primary diagnosis.

RESULTS

There were 4,365,578 ED visits with RTIs of which 321,719 (7.4%) were admitted to hospital; 817,141 ED visits for COPD of which 260,665 (31.9%) were admitted and 649,666 ED visits with asthma of which 68,626 (10.6%) were admitted. The percentage of positive tests to influenza A and B, respiratory syncytial virus (RSV), parainfluenza and adenovirus prevalence explained 57.4% of ED visits and 63.8% of hospitalizations for RTI, 41.4% of ED visits and 39.2% of hospitalizations with COPD but only 1.5% of ED visits and 2.7% of hospitalizations for asthma. The further addition of human metapneumovirus, rhinovirus and coronavirus over the final 3 years accounted for 66.7% of ED visits and 74.4% of hospitalizations for RTI, 52.5% of visits and 48.2% of hospitalizations for COPD, and only 13.3% of visits and 10.4% of hospitalizations for asthma.

CONCLUSIONS

Community respiratory viral epidemics are major drivers of ED visits and hospitalizations with RTIs and COPD but only a modest contributor to asthma.

Déclaration de conflit d'intérêts

IS reports grant from the ERS RESPIRE3 Marie Curie Award, BMA James Trust Award, North West Lung Centre Grant, personal fees from Merck MSD, AstraZenca, GSK, sponsorship to attend conference meetings, outside the submitted work; RC, JMG, KJK, NJ have no disclosures. PMO reports personal fees from oversight committee for LABA safety study, consulting fees from AstraZeneca, GSK, Merck, Boehringer, grants from AstraZeneca, Genentech, outside the submitted work. The research reported in this article was funded by an unrestricted grant from AstraZeneca Canada to PMO with no input in data collection, analysis, interpretation or writing of the manuscript. This does not alter our adherence to PLOS ONE policies on sharing data and materials.