Transmission of influenza A/H5N1 viruses in mammals

Influenza Virus Research Center, National Institute of Infectious Diseases, Musashimurayama, Tokyo 208-0011, Japan.
Virus Research (Impact Factor: 2.32). 08/2013; 178(1). DOI: 10.1016/j.virusres.2013.07.017
Source: PubMed


Highly pathogenic avian H5N1 influenza A viruses occasionally infect humans and cause severe respiratory disease and fatalities. Currently, these viruses are not efficiently transmitted from person to person, although limited human-to-human transmission may have occurred. Nevertheless, further adaptation of avian H5N1 influenza A viruses to humans and/or reassortment with human influenza A viruses may result in aerosol transmissible viruses with pandemic potential. Although the full range of factors that modulate the transmission and replication of influenza A viruses in humans are not yet known, we are beginning to understand some of the molecular changes that may allow H5N1 influenza A viruses to transmit via aerosols or respiratory droplets among mammals. A better understanding of the biological basis and genetic determinants that confer transmissibility to H5N1 influenza A viruses in mammals is important to enhance our pandemic preparedness.

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    • "In most cases, the individuals affected had been in close contact with infected poultry [1]. Concern exists that the virus could mutate to become more easily transmissible between humans, raising the possibility of an avian influenza pandemic for which the world is not adequately prepared [2]. Influenza A/H5N1 virus is one of the potential avian " pandemic " subtypes to which the majority of the human population has no preexisting antibodies and lacks immune memory [3]. "
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