More H7N9 cases can be expected in the next several weeks


Based on the reports from the People’s Republic of China (China), there is only limited human to human transmission of the novel A(H7N9) influenza virus.  However the number of sporadic cases reported by China is increasing dramatically.  The distribution of reported cases since November of 2013  has been increasing almost geometrically (graph below). Based on the trendline, between 30-40 cases per week may be expected within the next several weeks in China.


Graph notes: The weekly totals are counts based on reported onset dates for the 2013-2014 influenza season. The data do not include 18 cases announced in the past several days for which onset dates have not yet been reported.

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