Abysmal H3N2pdm11 Surveillance Raises Pandemic Concerns



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H1N1 Consulting Paradigm Shift Viral Evolution Intervention Monitoring Vaccine Screening Vaccine Development Expression Profiling Drug Discovery Custom Therapies Patents	Audio:Sep5 Sep15 Nov17 Dec1 twitter Commentary Abysmal H3N2pdm11Surveillance Raises Pandemic Concerns Recombinomics Commentary 21:00 December 09, 2011 Human infections with novel influenza A viruses normally found in swine are rare events. Recently, however, the frequency of such detections has increased. This could be occurring for a number of reasons, including one or more of the following factors: First, laboratory methods for testing for these viruses in the United States were improved following the 2009 H1N1 pandemic. These improvements may be resulting in viruses being identified now that would have gone undetected previously. Second, this could be due to increased surveillance in the United States for influenza at this time of year. CDC has requested that states analyze, and then send, their first influenza virus specimens of the season for seasonal influenza surveillance purposes. This practice, coupled with very low levels of seasonal flu activity at this time, could mean that sporadic novel influenza infections are more likely to be tested. Third, it is possible that the increased frequency of detection of novel influenza viruses with swine origins identified by CDC represents a true increase in the number of such cases, possibly occurring from exposure to infected swine or through subsequent, limited human-to-human transmission. The above comments from today’s CDC “Have You Heard” on the two novel human cases, trH1N2 (A/Minnesota/19/2011) and trH3N2 (A/West Virginia/06/2011) list possibilities for the increased detection of novel H1 and H3 triple reassortants, which ignores the sequence similarities between these isolates with the prior 2011 cases, H3N2pdm11. Other than the H1, all other gene segments in the H1N2 case are closely related to the 2010 human trH3N2 cases or the 2011 H3N2pdm11 cases. Similarly, the trH3N2 case matches the prior 2011 cases in all genes except the H2, which is closely related to swine H3N2 sequences. Thus, the close relationship between these human cases and the prior cases indicates several different triple reassortants are circulating in humans, and the abysmal surveillance described above, which target one case per state, limits the true picture of the frequencies, which appear to be alarmingly high in US children under the age of 10. Yesterday, the CDC released four more sequences from influenza A positive cases and all four were seasonal H3N2. However, the age was given for 3 of the 4 and all three were adults. In contrast, the two sets of sequences released today were from children under the age of 5 (the West Virginia case was 1F). These two cases raise the number sequenced under 10 influenza A cases to 14, and 11 of the 14 were closely related novel triple reassortants. Moreover, the five most recent cases had no swine exposure, and none of the prior 2011 cases have been linked to swine with confirmed SOIV infections. Thus, the current rate of infection in US children under the age of 10 is 79%, based on public sequences, yet there has been no enhanced surveillance of this demographic. The CDC continues to focus on targeting those with “swine exposure” and accidentally finding the widespread novel triple reassortants (trH1N2 and trH3N2), which now have been identified in 6 six states, in spite of abysmal surveillance. An active surveillance including sequencing of influenza A positive cases under the age of 10 is long overdue. Media Link Recombinomics Presentations Recombinomics Publications Recombinomics Paper at Nature Precedings

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