Remember the 2009 H1N1 influenza pandemic?  That brand new virus that caused the pandemic was a combination of RNA from four different flu viruses – North American swine influenza, North American avian influenza, human influenza, and swine influenza virus typically found in Asia and Europe.  The natural laboratories for new influenza viruses that end up causing pandemics (like the ’09 pandemic) are birds and pigs- so it’s important to pay attention to new viruses that emerge in these species so interventions can be implemented to manage outbreaks and potentially prevent human outbreaks or even pandemics. 

Last week Mexican veterinary authorities found a new strain of influenza virus called H7N3 that has been infecting and killing large numbers of poultry at several large commercial farms.  This is the first major outbreak in Mexican flocks since the country battled H5N2 influenza virus in the mid 1990s.  Luckily, there are no human cases and no suggestion yet that it is a kind of virus that can infect humans- but it’s still important to follow up on  Follow-up report No. 1 (25/06/2012)

By the way- the Influenza virus strains get their names from compounds called hemagglutinin and neuraminidase.  The H in the name refers to the kind Hemagglutinin on the virus and the N stands for the strain of Neuraminidase on the virus.