Commentary
H7 Q226L In Shanghai and Anhui H7N9 Cases
Recombinomics Commentary 20:15
April 1, 2013 The recent H7N9 cases in China have caused considerable concern. This serotype had never been found in humans previously and only one fatal bird flu case that was not H5N1 had been reported (H7N7 in The Netherlands in 2003. Two of the H7N9 cases were fatal (87M and 27M), while one was critical (35F).
The WHO Chinese Influenza Research Center released a full set of sequences for all three cases. Each had PB2 E627K, as well as a 15 BP deletion In N9. PB2 E627K is a mammalian adaptation and was present in both H5N1 transmission experiments (CDC and EMC) which used an avian PB2.
All three of the H5N1 transmission studies introduced the receptor bind domain change Q226L to increase affinity for mammalian receptors.
Q226L has never been reported in natural H5N1 isolates.
Two of the H7N9 cases, A/Shanghai/2/2013 and A/Anhui/1/2013 have Q226L, raising serious pandemic concerns.
Ho Hum
For all those who may be taking this lightly, we shouldn't discount the seriousness of this virus simply because we are seeing it so soon in its life. The speed of modern communication has somewhat unfortunately caused many of us to be cynical.
Ping! (Thanks Dr. Brian Kopp!)