Aerosol transmission is an important mode of influenza A virus spread

School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, Hong Kong, China.
Nature Communications (Impact Factor: 11.47). 06/2013; 4:1935. DOI: 10.1038/ncomms2922
Source: PubMed


Influenza A viruses are believed to spread between humans through contact, large respiratory droplets and small particle droplet nuclei (aerosols), but the relative importance of each of these modes of transmission is unclear. Volunteer studies suggest that infections via aerosol transmission may have a higher risk of febrile illness. Here we apply a mathematical model to data from randomized controlled trials of hand hygiene and surgical face masks in Hong Kong and Bangkok households. In these particular environments, inferences on the relative importance of modes of transmission are facilitated by information on the timing of secondary infections and apparent differences in clinical presentation of secondary infections resulting from aerosol transmission. We find that aerosol transmission accounts for approximately half of all transmission events. This implies that measures to reduce transmission by contact or large droplets may not be sufficient to control influenza A virus transmission in households.

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Available from: Piyarat Suntarattiwong, Feb 04, 2014
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    • "We have gained extraordinarily detailed knowledge in the past decade about the molecular nature of influenza virus and other respiratory viruses yet surprisingly little is known about how respiratory viruses are transmitted from person to person. Mathematical modelling of households, containing infected individuals, showed aerosol transmission to be more significant than contact transmission for influenza virus and that airborne transmission may be a significant contributor [1, 2]. Recent reviews of the literature support this important possibility [3, 4]. "
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