Outbreak of avian influenza H7N3- A mix of High & low pathogenic strain ?

[Mingus]

<dl class="PubmedArticle" id="dlPubmedArticle16997995"><dt class="head" id="head16997995">1: Vet Rec. 2006 Sep 23;159(13):403-5. <script language="JavaScript1.2"> <!-- var PopUpMenu2_LocalConfig_jsmenu3Config = [ ["ShowCloseIcon","yes"], ["Help","window.open('/entrez/query/static/popup.html','Links_Help','resizable=no,scrollbars=yes,toolbar=no,location=no,directories=no,status=no,menubar=no,copyhistory=no,alwaysRaised=no,depend=no,width=400,height=500');"], ["TitleText"," Links "] ] var jsmenu3Config = [ ["UseLocalConfig","jsmenu3Config","",""] ] //--> </script> <script language="JavaScript1.2"> <!-- var Menu16997995 = [ ["UseLocalConfig","jsmenu3Config","",""], ["Books","window.top.location='http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=pubmed_AbstractPlus&cmd=Retrieve&db=pubmed&list_uids=16997995&dopt=Books'","",""], ["LinkOut","window.top.location='http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=pubmed_AbstractPlus&cmd=Retrieve&db=pubmed&list_uids=16997995&dopt=ExternalLink'","",""] ] //--> </script> Links
</dt><dd class="abstract" id="abstract16997995">Outbreak of avian influenza H7N3 on a turkey farm in the Netherlands.

• Velkers FC,
• Bouma A,
• Matthijs MG,
• Koch G,
• Westendorp ST,
• Stegeman JA.

Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, po Box 80.151, 3508 td Utrecht, The Netherlands.
This case report describes the course of an outbreak of avian influenza on a Dutch turkey farm. When clinical signs were observed their cause remained unclear. However, serum samples taken for the monitoring campaign launched during the epidemic of highly pathogenic avian influenza in 2003, showed that all the remaining turkeys were seropositive against an h7 strain of avian influenza virus, and the virus was subsequently isolated from stored carcases. The results of a reverse-transcriptase pcr showed that a h7n3 strain was involved, and it was characterised as of low pathogenicity. However, its intravenous pathogenicity index was 2.4, characterising it as of high pathogenicity, suggesting that a mixture of strains of low and high pathogenicity may have been present in the isolate. The outbreak remained limited to three farms.
PMID: 16997995 [PubMed - in process]
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[Mingus]

Re: Outbreak of avian influenza H7N3- A mix of High & low pathogenic strain ?

So if a strain is on the way to high pathogenic revertance, the presence of a mix of strain may embloiled the sequencing data in a way we just see the low pathogenic sequence... if the low pathogenic is more expressed where it is swabbed.

It could be a real problem when the Quigai strain will encounter the now widespread north american Low path H5N1...
There is a strong possibility for false or irrepresentative sequencing data here.

 

[HenryN]

Re: Outbreak of avian influenza H7N3- A mix of High & low pathogenic strain ?

So if a strain is on the way to high pathogenic revertance, the presence of a mix of strain may embloiled the sequencing data in a way we just see the low pathogenic sequence... if the low pathogenic is more expressed where it is swabbed.

It could be a real problem when the Qinghai strain will encounter the now widespread north american Low path H5N1...
There is a strong possibility for false or irrepresentative sequencing data here.

Finding mixtures is common and the cloned serotype frequently does not match the original serotype as seen in the "notes" column on the wild bird isolates by OSU (who have the North American H5N1 from Maryland)

http://www.flutrackers.com/forum/showpost.php?p=34283&postcount=2