Canberra, ACT, Australia Transmission of Influenza Virus by Inhalation pathways – An Occupational Hygienists ’ view.

A cursory look into the infection control literature on the airborne transmission of infectious agents can make even the most hardened occupational hygienist wince. In a field that is currently highly controversial, this paper will review the background to some longstanding tenants in the field applied specifically to the transmission of Influenza virus. The published literature on modes of transmission, particularly the interface between airborne particle (<5micron) and droplet (>5micron) modes are examined. Coupled with experimental studies of bioaerosol generation and removal in a variety of environments, this demarcation on the grounds of particle size appears to abandon basic principles of aerosol physics. When viewed alongside recent work on the measurement of influenza virus particles in aerosol samples, an opinion based on occupational hygiene principles develops that supports the hypothesis that influenza virus may be transmitted via the airborne route