The 2011 H3N2pdm11 Pandemic Puzzle
November 29, 2011
WHO trying to hit the sweet spot in responding to puzzling new flu virus
The spread of an odd new flu virus that has been jumping from pigs to people in parts of the United States has the World Health Organization gearing up its response planning, a senior official of the agency says.
The above title and introduction are from a Helen Branswell piece on WHO preparations for the 2011 trH3N2 pandemic. The virus itself is not puzzling (or odd). In the US this trH3N2 was first reported in a Riley County fair attendee (12M) and the full sequence, A/Kansas/13/2009 was published at GISAIID followed by an EID report and release at Genbank.
Subsequent release of sequences from the human cases in 2009 and 2010 (A/Iowa/16/2009, A/Minnesota/09/2010, A/Wisconsin/12/2010, A/Pennsylvania/14/2010, and A/Minnesota/11/2010 led to a prediction of the trH3N2 pandemic on December 17,2010 and that prediction was reinforced by each announcement of trH3N2 cases in 2011,.
The large Iowa cluster, in the absence of swine exposure, was expected as was the WHO response. Similarly, the naming of the novel trH3N2 is also straightforward. The triple reassortant that cases the 2009 pandemic is named H1N1pdm09 (representing the H1N1 serotype and the year of the pandemic) and the novel trH3N2 causing the 2011 pandemic should be called H3N2pdm11.