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Confirmation of Avian Influenza H7N2 Infection in Wales

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  • #16
    Re: Confirmation of Avian Influenza H7N2 Infection

    Originally posted by Niko View Post
    If H7N2 were to combine with H5N1, would it result in a new (H?N?) avian influenza virus or would it be a new strain of H7N2 or H5N1? How different would the recombined virus need to be in order to be reclassified as a new virus? Please explain answer in lay terms, as much as possible. Thank you!
    The most common recombination events end up with the acquisition of a short region (either because the acquisition is short, or the new portion is trimmed back to a small region). Any recombinant has to compete with the two parental strains, so large acquisitions may not be very competitive.

    In the past I described the concurrent acquistion by a single nucleotide polymorphisms (the difference of one letter) onto multiple genetic backgrounds in Egypt, Russia, and Ghana. In each case the single nucleotide was appeneded onto the genetic background in the given region. This addition was on 11 sequences representing 6 H5N1 backgrounds.

    The same thing happened with M230I. In one series, the sequencing encoding the M230I on the H5N1 in Egypt matched the sequence in H7N3, so the acquisition of M230I involve a single nucleotide and the the amino acid at position 230 changed from M to I.

    It is this type of change that would convert H5N1 to a more efficient transmitter. In Egypt, there were 5 human isolates with M230I (4 had the coding seen in H5N1 in Germany, and 1 had the coding seen in H7N3 seen in England last year). There were also H5N1 poultry isolates with M230I. Most had the version seen in H7N3.

    In addition to the efficient transmission in the Gharbiya cluster, all human cases with H5N1 containing M230I were fatal.
    Last edited by HenryN; May 28, 2007, 03:46 PM.

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    • #17
      Re: Confirmation of Avian Influenza H7N2 Infection

      if H7 or H5 wanted to recombine, it looks more natural they
      would do it with other H7 or H5, not mixed.
      They can not gain much by mixing.

      If there are single-nucleotide-"recombination" (IMO random mutations),
      then why don't we
      see longer (2,3,..)-nucleotide-changes-recombinations ?
      I'm interested in expert panflu damage estimates
      my current links: http://bit.ly/hFI7H ILI-charts: http://bit.ly/CcRgT

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      • #18
        Re: Confirmation of Avian Influenza H7N2 Infection

        Originally posted by gsgs View Post
        if H7 or H5 wanted to recombine, it looks more natural they
        would do it with other H7 or H5, not mixed.
        They can not gain much by mixing.

        If there are single-nucleotide-"recombination" (IMO random mutations),
        then why don't we
        see longer (2,3,..)-nucleotide-changes-recombinations ?
        The M230I in most of the poutry in H5N1 in Egypt has the coding that matches H7N3, not H5N1.

        H5N1 knows how the game is played, and the story is VERY clear in the sequences.

        Here it is color coded. Position 754.

        White = H7N3

        Blue = H5N1

        Gold is wild type (230 is M)

        If you are not color blind, it is an easy call

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        • #19
          Re: Confirmation of Avian Influenza H7N2 Infection

          Originally posted by Commonground View Post
          I'm starting to write down the cases.
          I have positive: The pupil today, 2 from Wales and 2 from N. England. No names. Is that correct?
          I don't think it is clear that the pupil today isn't one of the two from Wales (the one with no poultry contact).

          If I had to guess, I would say the child's parent is the local vet who called in reinforcements (from north west England), so the four cases would be the vet and child from Wales, and two investigators from north west England.

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          • #20
            Re: Confirmation of Avian Influenza H7N2 Infection

            Avian influenza A virus (H7N7) associated with human conjunctivitis and a fatal case of acute respiratory distress syndrome





            link to the full article is below,not sure if this helps sorry if im barking up the wrong tree.





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            • #21
              Re: Confirmation of Avian Influenza H7N2 Infection

              Originally posted by vinny View Post
              Avian influenza A virus (H7N7) associated with human conjunctivitis and a fatal case of acute respiratory distress syndrome

              link to the full article is below,not sure if this helps sorry if im barking up the wrong tree.

              http://www.pubmedcentral.nih.gov/art...i?artid=337057
              The article's abstract mentions the possibility of an H7 pandemic.

              The acute respiratory distress syndrome brings back memories of SARS from a coronovirus.

              So an H7 or any other strain of virus that creates a pandemic, plus another opportunistic virus, suggests a pandemic with localized fatal outbreaks before the development of a more severe, or new strain, pandemic.

              That's different from the generaly assumed fowl-mammal-H2H local - H2H mass proliferation model.

              FT is justified, therefore, in closely following the development of other viral diseases. (aside from humanitarian grounds)


              J.

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              • #22
                Re: Confirmation of Avian Influenza H7N2 Infection

                Originally posted by cartski View Post
                The article's abstract mentions the possibility of an H7 pandemic.

                The acute respiratory distress syndrome brings back memories of SARS from a coronovirus.

                So an H7 or any other strain of virus that creates a pandemic, plus another opportunistic virus, suggests a pandemic with localized fatal outbreaks before the development of a more severe, or new strain, pandemic.

                That's different from the generaly assumed fowl-mammal-H2H local - H2H mass proliferation model.

                FT is justified, therefore, in closely following the development of other viral diseases. (aside from humanitarian grounds)


                J.
                H7 has always been a concern because of H2H, media reports and government pronouncements not withstanding. The linked article was on those positive for H7N7 sequences. The number positive for H7 antibodies was MUCH higher (over a thousand and counting when they stopped testing).

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                • #23
                  Re: Confirmation of Avian Influenza H7N2 Infection

                  Originally posted by cartski View Post
                  The article's abstract mentions the possibility of an H7 pandemic.

                  The acute respiratory distress syndrome brings back memories of SARS from a coronovirus.

                  So an H7 or any other strain of virus that creates a pandemic, plus another opportunistic virus, suggests a pandemic with localized fatal outbreaks before the development of a more severe, or new strain, pandemic.

                  That's different from the generaly assumed fowl-mammal-H2H local - H2H mass proliferation model.

                  FT is justified, therefore, in closely following the development of other viral diseases. (aside from humanitarian grounds)


                  J.
                  Influenza causes acute respiatory distress. In fact some investigators were looking at SARS because they initially thought it was avian influenza (the family from Hong Kong who visited Fujian province developed symptoms in early 2003, when the SARS coronavirus was taking off).

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                  • #24
                    Re: Confirmation of Avian Influenza H7N2 Infection

                    H7 viruses are also a concern, becuase, like H5 viruses they can convert into highly pathogenic forms quite readily, but not as readily as H5 viruses. H7 viruses will only become more pathogenic when additional amino acids are added to the cleavage site, whereas LPAI H5 viruses can become HPAI viruses by either an addition of an amino acid to the cleavage site or by substitution of an amino acid within the existing cleavage site.

                    Just becase its not particularly 'bad' at present, does not mean it will remain that way.

                    An H7N2 reassortment with H5N1 could be very bad indeed.

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                    • #25
                      Re: Confirmation of Avian Influenza H7N2 Infection

                      Originally posted by Vibrant62 View Post
                      H7 viruses are also a concern, becuase, like H5 viruses they can convert into highly pathogenic forms quite readily, but not as readily as H5 viruses. H7 viruses will only become more pathogenic when additional amino acids are added to the cleavage site, whereas LPAI H5 viruses can become HPAI viruses by either an addition of an amino acid to the cleavage site or by substitution of an amino acid within the existing cleavage site.

                      Just becase its not particularly 'bad' at present, does not mean it will remain that way.

                      An H7N2 reassortment with H5N1 could be very bad indeed.
                      That is incorrect. Both H5 and H7 can convert by adding or changing amino acids at the cleavage site.

                      There is no evidence that an H5/H7 reassortant would be bad.

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                      • #26
                        Re: Confirmation of Avian Influenza H7N2 Infection

                        Originally posted by niman View Post
                        That is incorrect. Both H5 and H7 can convert by adding or changing amino acids at the cleavage site.

                        There is no evidence that an H5/H7 reassortant would be bad.
                        Can you qualify "bad"? For instance, I would consider any novel virus that spreads easily H2H as "bad" regardless of mortality rate.
                        "In the beginning of change, the patriot is a scarce man (or woman https://flutrackers.com/forum/core/i...ilies/wink.png), and brave, and hated and scorned. When his cause succeeds, the timid join him, for it then costs nothing to be a patriot."- Mark TwainReason obeys itself; and ignorance submits to whatever is dictated to it. -Thomas Paine

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                        • #27
                          Re: Confirmation of Avian Influenza H7N2 Infection

                          Hi. Looking at the latest update from the National Public Health Service for Wales http://www.wales.nhs.uk/sites3/news....contentid=6796 Only two tests for H7N2 so far have been positive. I know initially they said there were four positives. I'm just wondering whether these other two might have been positive for type-A flu, but not an H7 subtype..? KBD

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                          • #28
                            Re: Confirmation of Avian Influenza H7N2 Infection

                            The first news release refers to H7N2 and specifies 4 persons. It could be badly written?

                            "...The Health Protection Agency is providing expert support and advice to the National Public Health Service for Wales after an H7N2 avian influenza infection was found in birds on a small farm in north Wales. The Agency has carried out tests on specimens from nine people associated with the incident; seven are from Wales and two were from north west England.
                            Four of the test results were positive - two of these were from Wales and two were from north west England.The remaining five test results came back as negative. However because these five cases were associated with the birds and had a compatible illness, they are being treated as a precaution.
                            H7N2 is a low pathogenic strain of avian flu...."

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                            • #29
                              Re: Confirmation of Avian Influenza H7N2 Infection

                              Originally posted by KBD View Post
                              Hi. Looking at the latest update from the National Public Health Service for Wales http://www.wales.nhs.uk/sites3/news....contentid=6796 Only two tests for H7N2 so far have been positive. I know initially they said there were four positives. I'm just wondering whether these other two might have been positive for type-A flu, but not an H7 subtype..? KBD
                              Two were positive in Wales and the other two were from north west England (so not covered by the Wales info). I have seen no hints that the two in north west England were not H7, which is a pretty specific assay and not easily confused with H1 or H3. Assuming the H7 positives in the north are false is a step beyond speculation, unless there has been a specific announcement to that effect.
                              Last edited by HenryN; May 29, 2007, 02:16 AM.

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                              • #30
                                Re: Confirmation of Avian Influenza H7N2 Infection

                                Originally posted by Florida1 View Post
                                The first news release refers to H7N2 and specifies 4 persons. It could be badly written?

                                "...The Health Protection Agency is providing expert support and advice to the National Public Health Service for Wales after an H7N2 avian influenza infection was found in birds on a small farm in north Wales. The Agency has carried out tests on specimens from nine people associated with the incident; seven are from Wales and two were from north west England.
                                Four of the test results were positive - two of these were from Wales and two were from north west England.The remaining five test results came back as negative. However because these five cases were associated with the birds and had a compatible illness, they are being treated as a precaution.
                                H7N2 is a low pathogenic strain of avian flu...."
                                It's not the press release that was badly written. It was quite clear that two were from the north west and two were from Wales.

                                I suspect the two from Wales were the vet and a family member (as in child), while the two from the north west were investigators called in by the local vet.

                                I am sure that the child's classmate know the student's identity and relationship to the farm. Since media reports also indicate that the farm owners initially had symptoms, they may have infected the child. Since the owners were tested late, they had probably already cleared the virus, so they were negative, but will almost certainly be positive in a convalescent antibody test.

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