G158E H1N1 Low Reactor In South Korea

Recombinomics has the story

Recombinomics Commentary 23:54
March 9, 2010
Recently released NIID sequences at GISAID include A/GYEONGGI/4478/2009, which has G158E and was collected on 9/11.  When G158E was reported in sequences from Germany, the CDC and Mill Hill independently determined that the isolates were low reactors, which was linked to G158E since it was the only non-synonymous HA change.  NIID also released a series of more recently collected isolates in Japan which also had G158E, which dramatically increased the number of public sequences with G158E.  Included in the isolates from Japan were sequences with D225N or H274Y.  These low reactors with clinically significant markers were in addition to isolates with the combination of G158E and D225G found in Italy and Russia.

The jump in these low reactor markers in Asia adds to the jump reported in the United States.  In the latest CDC report, the number of low reactors increased from 2 to 5.  An increase in low reactors was expected, as more of the target population develops immunity against wild type H1N1.  However, the low reactor, receptor binding domain, and anti-viral markers have been actively jumping from one genetic background to another via recombination, which increases the number of different combinations on different genetic backgrounds.

This rapid evolution raises concerns that there will be widespread vaccine failure against isolates that have resistance to anti-virals and cause more severe and fatal infections.