@book{JRC47466, editor = {}, address = {Stockholm (Sweden)}, year = {2008}, author = {Weber T and Stilianakis N}, isbn = {}, abstract = {Three different, mutually non-exclusive modes of influenza transmission have been identified and controversially discussed so far: droplet, airborne and contact transmission. One factor contributing to the relative importance of each of the three transmission modes is the inactivation of influenza A viruses in different environmental media. We systematically review available information on the environmental inactivation of influenza A viruses and combine these data with information on infectious dose and with results from novel mathematical models to evaluate the relative importance transmission modes. Our analysis shows that daily inactivation rate constants differ by several orders of magnitude: on inanimate surfaces and in aerosols daily inactivation rates are in the order of 1 ¿ 102, on hands in the order of 103, i.e. influenza virus can survive in aerosols for several hours, on hands for a few minutes. Nasal infectious dose of influenza A is several orders of magnitude larger than airborne infectious dose. We conclude that the airborne route is a potentially important transmission pathway for influenza in indoor environments and that the importance of droplet transmission has to be reassessed. Contact transmission can be limited by fast inactivation of influenza virus on hands and is more so than aerosol transmission dependent on behavioural parameters. However, the potentially large inocula deposited in the environment through sneezing and the protective effect of nasal mucus on virus survival could make contact transmission a key transmission mode. }, title = {Inactivation of Influenza a Viruses in the Environment and Modes of Transmission}, url = {http://www.escaide.eu/en/articles/escaide/program-2.cfm}, volume = {}, number = {}, journal = {}, pages = {128}, issn = {}, publisher = {European Centre of Disease Prevention and Control (ECDC)}, doi = {}