faulker024

On January 24 th ,   I posted a graph plotting the growth rate of H7N9 cases in China. Based on the trend (link), I estimated that between 30-40 cases of H7N9 would be reported in the coming weeks. Using current data for onset dates (through February 4, 2014), an updated plot indicates a total of 39 H7N9 cases for both Week 4 and Week 5. More than 30 H7N9 cases (without onset dates) have already been reported for Week 6. If the number of cases continues to increase at an exponential rate, more than 100 people a week will be reported as H7N9 cases by Week 7 or Week 8.   If the rate continues at its current pace, China will be experiencing an H7N9 epidemic within the near future. Current graph of H7N9 cases through Week 5.

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.