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  •  i have a question (1+ / 0-)
    Recommended by:
    jnhobbs

    processing of flu samples is backlogged to, like, july, right?  so how can they be confident in saying there's been no mutation?

    thanks!

    I know reccing a diary feels like forwarding a funny email, but the rec list can only hold 8 items, unlike email inboxes. Think before you rec!

    by Cedwyn on Fri Nov 13, 2009 at 07:06:13 AM PST

    •  If they find there IS a mutation (1+ / 0-)
      Recommended by:
      riverlover

      in samples they have not yet tested, your options are the same: get the H1N1 vaccine if it's available to you.

      Also, viruses don't tend to mutate drastically in the middle of an epidemic.  Mutations tend to occur (or more accurately, are selected for) prior to an epidemic which is what causes epidemics to happen.  Once the virus moves efficiently from person to person that strain dominates.

      "All this marching up and down and cheering and waving flags is simply sex gone sour." -Julia, 1984

      by pullbackthecurtain on Fri Nov 13, 2009 at 07:17:16 AM PST

      [ Parent ]

      •  Huh? (2+ / 0-)
        Recommended by:
        Cedwyn, CMYK

        How do they find H1N1 in untested samples? If they're untested, they haven't looked in them.

        And your logic about mutation in epidemics doesn't work. While it's true that mutations in genes controlling transmission are what causes epidemics, there's nothing stopping other genes, that cause different symptoms (like death) from mutating. Indeed, during an epidemic the individual viruses vastly increase in number and therefore exposure to different environmental factors, which increases the chance of mutations. So epidemics are times when mutation frequency can increase.

        "When the going gets weird, the weird turn pro." - HST

        by DocGonzo on Fri Nov 13, 2009 at 07:33:33 AM PST

        [ Parent ]

        •  true, but most mutations in viruses as in (0+ / 0-)

          other organisms are either lethal to the virus, or indifferent in causing disease. It takes time for a more efficent mutation to take hold.

          Necessity is the argument of tyrants; it is the creed of slaves.-- Wm.Pitt the Younger

          by JeffSCinNY on Fri Nov 13, 2009 at 07:42:29 AM PST

          [ Parent ]

          •  True, But (1+ / 0-)
            Recommended by:
            CMYK

            That is always true of most genetic mutations. The occurrence of an epidemic does not slow or inhibit the rate of mutation, or discriminate among types of expressions of them (organism traits, like those that cause symptoms). Indeed, an epidemic offers an environment that can increase the frequency overall, and symptom-causing mutations along with it.

            "When the going gets weird, the weird turn pro." - HST

            by DocGonzo on Fri Nov 13, 2009 at 07:51:14 AM PST

            [ Parent ]

        •  sigh... (0+ / 0-)

          How do they find H1N1 in untested samples? If they're untested, they haven't looked in them.

          in samples they have not yet tested, your options are the same: get the H1N1 vaccine if it's available to you.

          The original poster was talking about a "back log" of samples.  Hence my use of the word YET which means 'something that will eventually occur but has not occurred at the present time'.

          there's nothing stopping other genes, that cause different symptoms (like death)

          would you care to let us know what gene causes the symptom of death?

          Genes encoding surface glycoproteins (what you call "genes controlling transmission") are what mutate.  These are HA and NA (and the first 23 amino acids of M2, the extracullular portion of the protein).  These are what are recognized by antibodies.  When a large portion of the population has antibodies that efficiently recognize epitopes the virus does not transmit effectively.  Mutations in these genes (genetic drift, point mutations) alter the antigenic signature.  When a mutant forms that is not easily recognized by previous antibodies, AND that binds to the cell surface receptor, then it can transmit effectively between people.  Internal proteins are not subject to this pressure as they are not recognized by neutralizing antibody.

          Yes, it's true the absolute number of viral particles in existence during an epidemic are greater and therefore, statistically speaking the number of mutant viruses are also greater.  But you are missing the point of epidemics and natural selection here.  One strain dominates because it is the most effectively transmitting and replicating virus.  the original poster was implying a possibility of ineffective vaccination due to mutant variants arising during the pandemic.

          I suggest you stop speaking as an authority on biology when you clearly are not.

          "All this marching up and down and cheering and waving flags is simply sex gone sour." -Julia, 1984

          by pullbackthecurtain on Fri Nov 13, 2009 at 08:03:39 AM PST

          [ Parent ]

          •  Your Authority (0+ / 0-)

            Your first statement was probably just poorly articulated, since what you actually said was absurdly impossible. But that got me to thinking about the rest of what you said, which was that viruses don't mutate during epidemics because they mutated before the epidemic into a form fit enough to multiply enough to become an epidemic.

            Now you're going deeper into the mechanisms of transmission. But you're still ignoring (and implicitly denying) that the increased virus population during an epidemic offers increased chances for mutation. You're talking like the mutation achieving "success" in reproduction is some kind of protection against further mutations, which are random but proportional to the exposure of genomes to an environment that mutates them. Before the natural selection eliminates those that cannot reproduce, the number of mutations can increase because the number of mutable genomes is greater. There certainly is no inhibitor in the epidemic to further mutations. Which is all that I'm actually saying, and which is at odds with what you're saying: that viruses don't mutate during an epidemic.

            What I have said is valid. You have not even directly addressed what I've said, while trying to equate what I said with what another post said about vaccines, which is not correct. You haven't earned a condescending tone or any assumption of authority here, especially if your actual logic is as unconvincing as what you've wrapped in your unpersuasive rhetoric.

            "When the going gets weird, the weird turn pro." - HST

            by DocGonzo on Fri Nov 13, 2009 at 11:16:47 AM PST

            [ Parent ]

            •  my authority > your authority (0+ / 0-)

              increased virus population during an epidemic offers increased chances for mutation

              the chance of a mutation occuring in a piece of DNA is the same regardless of how many copies of the DNA are present.  It's based on the error rate of the polymerase during replication.

              What you mean here is because there are more viruses replicating (in more people) there are more errors created.  This is true.  But it has nothing to do with the "chance for mutation".

              Before the natural selection eliminates those that cannot reproduce

              Natural selection doesn't eliminate anything.  It NATURALLY SELECTS the one which has the best chance at survival.  All others sputter out as they can't compete.  And that virus that spreads like wildfire during an epidemic (not alone PANDEMIC)...guess what that is?!  Also, professor...viruses don't reproduce.  They replicate.

              There certainly is no inhibitor in the epidemic to further mutations.

              There is no inhibitor to mutations period.  Ever.  Mutations are just that-random unavoidable changes to genetic structure.  But again I think what you mean is not what you are saying.  I think you mean 'there is nothing stopping the virus from mutating further while an epidemic is going on'.  This is true.  But your definition of 'mutate' is probably different from mine.  You are probably thinking of the virus on a macro, population level.  Such as if the virus mutates you mean the PREVALENT virus which right now is A/CA/04/2009 or at least has its genetic identity.  Well here is where you're wrong (if that is indeed what you mean).  The influenza spreading around right now in 99.5% of the cases is A/CA/04/2009.  In week 44 alone there were 1,400 laboratory confirmed cases.  200,000 people will be hospitalized.  Those 200,000 people will spread it to countless others.  Yet you believe that somewhere out there a random mutation will occur which will allow it to spread even more efficiently to people?  Okay, lets say it does.  That one strain mutation then spreads to 20 other people.  Those 20 people spread it to 20 more.  In a completely naive population you would have the start of an epidemic.  But the problem is it has to compete with the one that has already been exposed to millions of people.  And those people will have antibodies to H1N1.  Human beings are the 'food' source if you will for the flu.  The virus spreading right now has emerged as the dominant virus and no other H1N1 can compete with it.  It's numerically impossible.  It can't be selected over by a mutant with such a close antigenic signature.  That is why the flu season is marked every year by ONE dominant strain.  

              And finally I'm not trying to persuade you with anything.  These replies are for the others reading this who may make the mistake of thinking you know what you are talking about.

              Again, go get an advanced degree in biology or immunology and then try to talk about something like this.  I did.

              "All this marching up and down and cheering and waving flags is simply sex gone sour." -Julia, 1984

              by pullbackthecurtain on Fri Nov 13, 2009 at 02:18:09 PM PST

              [ Parent ]

              •  Not So Smart (0+ / 0-)

                You're the one who tried to say that a virus that's succeeding in multiplying doesn't mutate during its successful period after the mutation that made it successful. That's wrong.

                Which is more important than whether I say "reproduce" instead of "replicate". Which is how viruses reproduce, despite your failed attempt to make a semantic argument. Now tell me that you're not a PhD linguist or something to excuse your failed attack on that line.

                More viruses in the environment increase the chance of mutation, because the randomness of mutation has a frequency that's proportional to the number of virus particles exposed to mutagens. Mutations happen during lifecycle phases other than transcription, but even so more viruses means more chances for whatever causes a mutation to cause it.

                Here's another lesson for you, hacker: natural selection eliminates those not selected. That's how selection works. The ones that fail to reproduce because the environment prevented them (AKA they were unfit to reproduce in that environment, usually because the environment killed them - or otherwise destroyed their perpetuation, since you'll whine that viruses aren't really "alive") are eliminated. The elimination of the unfit is as important as the survival and reproduction of the fit. So indeed natural selection eliminates just as it preserves.

                Here's some more free clues for you. I'm the one that said there's no inhibitor to mutation. You're the one who implied that epidemic multiplication comes with some inhibitor to mutation, the entire root of this subthread (in which you're faring increasingly poorly). You go to great lengths to put words in my mouth - a strawman - when all I'm saying is that viruses do mutate during epidemics, and indeed epidemics offer even more chances for mutation than lesser scale multiplication. I never said a mutation would dominate and eliminate the old dominant strain - you did. Go argue with some AIDS patients about how they can't have a mutated HIV during the epidemic. They'd be very happy if you could prove their doctors wrong. But you can't, so don't bother them. Leave that for me, who can handle people like you.

                People who pretend they're not trying to persuade me of anything, just because you can't, because your reasoning is faulty. If your reasoning were correct, there would be only one flu, but there's the ordinary seasonal one overlapping with the H1N1 in this epidemic. You're not going to impress an audience if all you're doing is grandstanding for them, without meeting my arguments with anything but fallacies - and lies about who said what.

                Your "argument from authority" (look it up) doesn't make you right. Your certifications just make you more wrong. Spending time getting them instead of learning to be right, or at least to learn when you're wrong.

                Viruses can mutate after they've already mutated to a form that enables an epidemic. You said they don't. You're wrong. Get on the right track by admitting it already. Your piece of paper that you think says your right isn't impressed, either.

                "When the going gets weird, the weird turn pro." - HST

                by DocGonzo on Sun Nov 15, 2009 at 09:16:39 PM PST

                [ Parent ]

                •  ... (0+ / 0-)

                  who is putting up strawmen again?

                  You from above:

                  But you're still ignoring (and implicitly denying) that the increased virus population during an epidemic offers increased chances for mutation.

                  You:

                  You're the one who implied that epidemic multiplication comes with some inhibitor to mutation

                  Must be real easy to argue against me on things I never said by just throwing the phrase 'you implied' in front of it.  The reason you believe I implied it is either because you don't understand what it is you're reading or because you need something to argue against rather than what I'm ACTUALLY saying.

                  As for your little linky of someone writing the word 'reproduce' in the same sentence with the word 'virus' so what.  I can give you a link to a UC Berkley Professor that claims HIV doesn't cause AIDS.  That doesn't make him any less a fool for saying it.  Reproduction (sexual and asexual) is how an organism passes it's genes on to progeny.  Viruses are not organisms.  Now, to save you and google the time there is no shortage of people out there who incorrectly call them organisms.  But they are not.  Viruses are mobile genetic elements surrounded in a protein coat.  They evolved from transposons (genes within mammalian DNA that make copies of themselves and move to other places within the genome).  Just because someone says 'viruses need host cells to reproduce' doesn't mean viruses actually propagate via reproduction.  If we are going to start claiming that viruses reproduce inside cells then I guess we could also say that some loose DNA in my saliva also reproduces if I put it in a tube with some Taq polymerase and some dNTPs.  It's an example of people using words incorrectly and is how misinformation gets passed around.

                  If your reasoning were correct, there would be only one flu, but there's the ordinary seasonal one overlapping with the H1N1 in this epidemic.

                  There is no ORDINARY SEASONAL flu overlapping right now.  If people are getting the flu...its the H1N1.  This doesn't mean it's not possible for an H3N2 or an H2N2 to also spread.  They are antigenically different enough that one will not preclude the other from causing an epidemic.  So you're correct that H1N1 CAN coincide with an H3N2 (what you call ordinary seasonal) but you're wrong in assuming it's going around.  Because it JUST isn't:

                  CDC:

                  All subtyped influenza A viruses being reported to CDC were 2009 influenza A (H1N1) viruses.

                  You're saying nothing stops a virus from mutating during an epidemic.  I'm NOT disagreeing with you.  You're saying more total viruses present offers greater chances for mutation.  I'm disagreeing with you because the "chance" for mutation doesn't change anymore than the chance that a coin flip will land 'heads up' after tossing it in the air 5 times versus 50 million times.  It's always 50%.  When you say "chance for mutation" I think what you mean is the genetic identity of the virus currently spreading amongst the population.  Like some sort of science fiction movie where halfway through the movie things go from bad to worse when 'the virus mutates!' and suddenly it's worse.  That won't happen because the current virus already spreads very efficiently that there is little to no improvement that could be made.  It's nearly perfect.  And even if it DID improve in how it could spread it STILL COULDN'T compete with A/CA/04/2009 because it will have the same antigenic signature and therefore the vaccine, and all the H1N1 already out there will be inducing neutralizing antibodies in tens of millions of people.  It simply can't catch up.

                  This all takes us back to my orignial comment when you started trolling with your idiocy:

                  Also, viruses don't tend to mutate drastically in the middle of an epidemic.  Mutations tend to occur (or more accurately, are selected for) prior to an epidemic which is what causes epidemics to happen.  Once the virus moves efficiently from person to person that strain dominates.

                  The virus mutated, became A/CA/04/2009, spread efficiently from human to human, and has dominated ever since.

                  You can type all the bullshit you want, throw all the 'you implied' in there you want, claim my education is bunk all you want, and claim I'm "faring poorly" all you want.  You don't know what you're talking about and the more you try to defend your ignorance the more I will continue to point it out.

                  "All this marching up and down and cheering and waving flags is simply sex gone sour." -Julia, 1984

                  by pullbackthecurtain on Mon Nov 16, 2009 at 09:16:46 AM PST

                  [ Parent ]

                  •  Bunk (0+ / 0-)

                    You:

                    Mutations tend to occur (or more accurately, are selected for) prior to an epidemic which is what causes epidemics to happen.

                    That's where you imply that mutations are more frequent before an epidemic than during one. That's wrong, and illogical. You refuse to acknowledge that the increased exposure of the virus genome to a consistently mutagenic environment increases the chances of any single mutation event, therefore an increased probability of mutation, therefore an increased mutation rate. Not the chance of an individual mutation, that I never said, but the overall chances and therefore rates of any mutation in the genome everwhere it's reproducing, which is what I actually said. Strawman after strawman.

                    As I said, replication is a virus' way of reproducing. You're not getting anywhere denying the credibility of a scientist using "virus reproduction" in a scientific journal that has no other question as to its credibility, while citing your own credentials as proof you're right, when other questions about your credibility have such damning answers.

                    "When the going gets weird, the weird turn pro." - HST

                    by DocGonzo on Mon Nov 16, 2009 at 10:31:17 AM PST

                    [ Parent ]

                    •  That's not a scientific journal you cited (0+ / 0-)

                      its a FAQ sheet from a medical awareness .org site.

                      "Imply" is another word for 'I think you mean' which is serving you to continue this ridiculous tantrum.  Everything with you is 'imply'.

                      Virus genomes are not being exposed to mutagenic environments.  They mutate as a result of random errors in the replication process from the host cell polymerase.  Mutagenic environments, or mutagens, are chemicals or energy that alter DNA.  It is associated with cell damage due to things like UV light, free radicals or fixatives.  When people talk about 'mutagens' or 'mutagenic environments' that does not apply to viruses in a host cell.  Those genomes are subject to mutation via RNA and DNA polymerase error rate, not chemicals or radiation.  Chemicals and radiation mutate cellular DNA by crosslinking nucleotides (that would kill a virus) or replacing bases with incorrect ones according to the replication sequence (aka a polymerase or proofreading error).  People and their cells are exposed to mutagens and mutagenic environments, viruses are subject only to the polymerases.

                      I indeed chose my words poorly when I typed

                      Mutations tend to occur

                      as the individual mutations occur at the same rate regardless.  I have since chosen my words much more carefully as I've repeated over and over again in all the subsequent posts about how the rate doesn't change.  It's a constant.  What increases is the likelihood of a highly transmissible variant to emerge and be capable of spreading throughout a population.  But in an environment where a similar virus is already spreading rampantly throughout a population, such variants cannot compete for all the reasons you continue to ignore as you defend your poor use of scientific terms.

                      So if you're abandoning all your substantive arguments in favor of defending your poor use of scientific nomenclature and pointing out that one sentence in my original post that was poorly worded then kudos to you.  You've succeeded.

                      I particularly liked your last sentence where you waved your hands and a FAQ sheet became a 'scientific journal' while another waving of your hands and suddenly questions of my credibility have "damning answers".  Those are very impressive and most definitely 'words'!  How very convenient for you that you can create fact out of thin air just by typing!

                      Any comment on your claim that seasonal influenza is going around concurrently with H1N1?  

                      Any examples you'd like to cite where another virus enters into the population, is passed easily from person to person and yet phenotypically distinct mutants emerge from it whose antigenic characteristics are maintained?

                      Would you like to comment on what the chances for mutation of influenza virus are during replication when there is no epidemic?  Ok, and what are those chances DURING pandemic?  I want numbers here, not hand waving and links to FAQ sheets.  If you think I'm giving you an impossible task with this last one I'd be happy to post them if you don't.

                      "All this marching up and down and cheering and waving flags is simply sex gone sour." -Julia, 1984

                      by pullbackthecurtain on Mon Nov 16, 2009 at 12:25:22 PM PST

                      [ Parent ]

                      •  That's Enough (0+ / 0-)

                        Finally:

                        I indeed chose my words poorly when I typed

                        Mutations tend to occur

                        as the individual mutations occur at the same rate regardless.

                        That's good enough for me.

                        The rest of the blather I get from you isn't. And no sign of anything better to come. Goodbye.

                        "When the going gets weird, the weird turn pro." - HST

                        by DocGonzo on Mon Nov 16, 2009 at 12:57:38 PM PST

                        [ Parent ]

                        •  A simple mind (0+ / 0-)

                          satisfied with a simple victory.

                          Now you can go back to being entertained by shiny things!

                          For anyone else following along the chance for mutation of influenza virus normally is:

                          1 in 200,000  

                          During an epidemic the chance is 1 in 200,000.

                          Source: a REAL scientific journal

                          Parvin et. al. J. Virology 1986. 377-383

                          "All this marching up and down and cheering and waving flags is simply sex gone sour." -Julia, 1984

                          by pullbackthecurtain on Mon Nov 16, 2009 at 01:46:21 PM PST

                          [ Parent ]

                          •  Simplicity (0+ / 0-)

                            Yes, I was satisfied with getting you to finally admit that you "chose your words poorly", AKA, were wrong.

                            Anyone else reading this thread will surely notice that you're still insisting that they weren't wrong.

                            Simple minds like mine don't keep arguing with people who contradict themself so blatantly. Too dark for me.

                            You may now continue to take cheap but meaningless shots in my presumed absence.

                            "When the going gets weird, the weird turn pro." - HST

                            by DocGonzo on Mon Nov 16, 2009 at 06:15:06 PM PST

                            [ Parent ]

    •  they sample virus from all over (1+ / 0-)
      Recommended by:
      jnhobbs

      and so does Europe, and there isn't a backlog form July. The backlog is run in the following weeks, on an ongoing basis, in  a rolling fashion.

      "Politics is the art of looking for trouble, finding it everywhere, diagnosing it incorrectly and applying the wrong remedies." - Groucho Marx

      by Greg Dworkin on Fri Nov 13, 2009 at 07:22:38 AM PST

      [ Parent ]

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