10th International Aerosol Conference
September 2 - September 7, 2018
America's Center Convention Complex
St. Louis, Missouri, USA

Abstract View


Influenza Virus Maintains Infectivity in Droplets and Aerosols Independent of Relative Humidity

Karen Kormuth, Kaisen Lin, Aaron Prussin II, Eric Vejerano, Andrea Tiwari, Steve Cox, Mike Myerburg, Seema Lakdawala, LINSEY MARR, Virginia Tech

     Abstract Number: 60
     Working Group: Infectious Bioaerosol

Abstract
Previous studies have suggested that humidity contributes to the seasonality of influenza because the virus appears to survive better in droplets and aerosols under cold, dry conditions. However, there are conflicting findings about virus viability across the full range of relative humidities (RHs). Our objective is to determine the relationship between RH and influenza virus viability in droplets and aerosols of physiologically realistic composition. We exposed a circulating strain of influenza virus (2009 pandemic H1N1) in both stationary droplets and suspended aerosols to RHs ranging from 23% to 98%. The virus was prepared in a 1:10 mixture of human bronchial epithelial extracellular material and L-15 media. Over the 1-hour exposure period, the virus did not lose infectivity at any of the RHs tested. Our data suggest, for the first time, that influenza viruses remain highly stable and infectious in aerosols, independent of RH. When the extracellular material was heat-treated to denature proteins, the virus did not survive as well, particularly at RHs around 50%, as seen in prior studies. A parallel experiment with the enveloped bacteriophage Phi6 showed that the human bronchial epithelial extracellular matrix conferred a protective effect on this virus, too, and confirmed that viability in stationary droplets was similar to that in suspended aerosols. These results have significant implications for understanding the mechanisms of transmission of influenza and its seasonality.