Recombinomics | Elegant Evolution






Home Founder What's New In The News Consulting





























H1N1 Consulting

Paradigm Shift

Viral Evolution

Intervention Monitoring

Vaccine Screening

Vaccine Development

Expression Profiling

Drug Discovery

Custom Therapies

Patents 




A/V Dec18 Dec22 Dec31 Jan9 RSS Feed twitterNews Now                         

Commentary

Fujian H5N1 Reassortant In Whatcom County Washington
Recombinomics Commentary
January 21, 2015 23:45

As part of the increased AI surveillance of wild birds (performed by testing hunter harvested birds), another Eurasian H5 clade 2.3.4.4 virus has been identified through whole genome sequencing of the virus isolate. Introduction of the Eurasian (EA) H5N8 virus into the Pacific Flyway sometime during late 2014 has allowed mixing with North American (AM) lineage viruses and generated new combinations with genes from both EA and AM origin (or “reassortant” viruses) such as the EA/AM H5N2-reassortant detected in Canada and the United States. Such findings are not unexpected as the EA-H5N8 virus continues to circulate. A novel EA/AM H5N1-reassortant clade 2.3.4.4 was isolated from an American green-winged teal in Whatcom County, Washington. This H5N1 subtype is different from strain circulating in Asia. The gene constellation is as follows: Eurasian lineage genes (PB2, H5, NP, MP >99% identical to A/gyrfalcon/WA/41088/2014 H5N8); North American lineage genes (PB1 {98% identical to A/Northern pintail/Washington/40964/2014 H5N2}, PA, N1, NS of North American LPAI wild bird lineage. The HA cleavage site is compatible with strains that are highly pathogenic. This novel HPAI EA/AM H5N1-reassortant virus has NOT been found in commercial poultry anywhere in the United States.

The above comments from today’s OIE report on the detection of H5N1 in a wild American green winged teal near Sumas in Whatcom County, Washington (see map) is the first reported case with this sero-type as well as the first complete description of the constellation of gene segments.  Prior comments on the H5N2 reassortant in Canada noted a constellation of 5 Eurasian gene segments, including the H5, and 3 North American gene segments, including the N2, which gave the ratios, but failed to designate the origins for the six internal gene segments.  Moreover, subsequent descriptions by the CFIA were silent on the constellation ratios, raising the possibility of multiple constellations with the H5N2 sero-type.

The above description of the novel reassortant with four Eurasian gene segments (PB2, H5, NP, MP) and four from North America (PB1, PA, N1, NS) increases the likelihood that there are multiple constellations for H5N2 and H5N1, as well as additional H5 serotypes.  This possibility is support by three reported sero-types in Taiwan (H5N2, H5N3, H5N8) all of which have a Fujian H5 (clade 2.3.4.4, formerly called 2.3.4.6) closely related to the H5 in the H5N8 reported in the Korean outbreak in early 2014.  The N2 and N3 in Taiwan have Eurasian origins, highlighting the high frequency of reassortment.  Like the H5N2 in North America, detail on the constellations of the various isolates has not been released.

Two of the Eurasian segments in the H5N1 reassortant (H5 and MP) trace back to Fujian H5N1, while the other two (PB2 and NP) are found in H6N1 wild birds in Eurasia.  The gene segments may facilitate a high rate of reassortment, and the migration of H5N8 to North America allows for a wide diversity in constellations, including additional serotypes.
More information on constellation and release of sequences from Genbank would be useful.

Media Link

Recombinomics Presentations

Recombinomics Publications

Recombinomics Paper at Nature Precedings















Home | Founder | What's New | In The News | Contact Us

Webmaster: webmaster@recombinomics.com
© 2015 Recombinomics.  All rights reserved.