13 Recent H1N1 Deaths In Michigan Raise Concerns
Recombinomics Commentary February 11, 2010
Cumulative deaths associated with any influenza strain since Sept 1, 2009: 79The above comment in the most recent Michigan update describes a dramatic spike in H1N1 fatalities in the past 2 weeks in Michigan. This recent rate of approximately 1 death per day is in marked contrast to deaths between December 12, 2009 and January 19, 2010 when only 2 fatalities were reported. The spike in Michigan coincides with a spike in Pneumonia and Influenza deaths in the US, but in Michigan the spike was in lab confirmed H1N1, raising concerns that a new wave has begun in the US and is more lethal than the wave which largely ended in December and early January.The start of a new wave is not unexpected. Multiple waves within one pandemic seasonal have been noted previously, and the likelihood of a wave in early 2010 was increased by the early appearance of the fall wave, as well as the absence of seasonal influenza A. Moreover, the decline in wild type H1N1 provides an opportunity for the emergence and dominance of a new strain. Recent increases in the reporting of H1N1 sequences with D225G and D225N have raised concerns that this lethal strain could become more common leading to more severe and fatal cases.There has also been a recent surge in H1N1 confirmed fatalities in Mexico, raising additional concerns for the spread of D225G. In a recent series of 10 HA sequences from fatal cases in Mexico, 5 had D225G, D225N, or both. The two sequences with both were collected within a day of each other in San Luis Potosi, raising concerns of H225G/N transmission, which was recently seen in a death cluster at Duke Medical Center in North Carolina.