Two Tamiflu-resistant swine flu cases reported in Washington

[HenryN]

Re: Two Tamiflu-resistant swine flu cases reported in WA

I take it by this very surprising response that it is your view that the existing Swine Flu cannot reassort with Seasonal Flu to acquire only the NA segment making it Tamiflu resistant.

Otherwise, none of this makes any sense, or you have just misinterpreted the question posed.

Many of us in our responses agree with you on your recombination theory of Tamiflu resistance acquisition, but a reader would not necessarily get that impression by the way you respond to our posts on this forum. You simply say "no" or "wrong" to anything anyone else posts.

There is quite a bit of data on swine H1N1 acquiring H and N human genes. I don't know of any instance where one was acquired without the other, Swine H3N2 is now fairly widespread and both the H3 and N2 are human. In the earlier series on Canadian swine in 2003/2004, most isolates had human PB1 with seven other swine genes. Two had human H and N (I believe they were both H1N2), and one had all 8 gene segments (thus none had a human H with a swine N or a human N and a swine H). Same is true for the recent "novel" isolate in Sasketchewan. It was a triple reassortant (it wasn't clear if it was H3N2 or H1N1 prior to the acquisition of human H1 and N1) and acquired Bribane/59 H1 AND N1 (and the N1 had H274Y).
I didn't say that picking up N1 without H1 was likely and I know of any such example (human N1 with swine H1 or swine H3).
If you know of such and example, post it. I asked GS for an example and he posted ZERO.
I didn't say human N1 with swine H1 made sense. WHO and CDC did, as did media reports, but they are fixated on reassortment and as seen by the nonsense about a concern that acquisition of N1 from brisbane/59, they have no current examples (without also acquiring a human H1), and I doubt that they have any prior examples.

[HenryN]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

I admit to being confused even after Niman explained.

By the little summary I posted, I thought it was clear that the resistance developed "in" both people and was not the result of seasonal combining with panflu (or silent spreading). Considering that a certain percent of people will normally develop a resistance to Tamiflu, I just imagined this was much better than if it had combined.

It wasn't at all clear that the resistance developed "in" the patient. It just expanded in the patients (like Singapore, were the resistance was present 2-3 days after the start of treatment - too soon for de novo H274Y).

[DrRugby]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

OK, let's review some basic science influenza epidemiology.

First, influenza is unique in many ways but the reassortment into a novel virus has never been documented in human beings, chickens nor domesticated ducks.

It is hypothesized that it might occur in swine, though it is known to widely occur in certain duck species, mallard being the best documented.

This is because, for re assortment into a viable virus to occur, the host must not have an immune response to either the progenitor viruses nor the product virus.Otherwise, it would never survive to adequate quantities to be spread from the re assortment organism.

More later, got to go see some patients.

[DrRugby]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

Where was we? Oh yeah.

The 3 elements of influenza evolution.

The mixing bowl and intercontinental transport: the wild mallard and a few other species of intercontinental travel. (Have to not have any immune reaction to influenza, other wise dead birds don't fly very far. Exception, H5 is so pathogenic that even the transport birds seldom complete their migration before mounting some sort of reaction. Remember, with influenza it is not the VIRUS that kills, it is the body's immune reaction that kills the patient.)

The ultimate recipient of interest to us, meaning, us, humans.

The middle man species- swine, domesticated ducks, turkeys, ferrets, chickens, crows, grouse, some pigeons. They have to have both upper respiratory receptors for human and the migrating, mixing bowl species. If not they, the virus selected can not be guaranteed to infect humans. THIS is why we have not had a bird flu, H5, pandemic yet.

Over 460 persons have been infected with H5 thus far but this is due to the heavy innoculum received from long time proximity to the infected domesticated birds & ducks. So heavy is the infection that it has to reach the lower respiratory receptors in sufficient quantity to cause infection.

The same probably occured with some of the H1N1 with the slaughter houses in Mexico and in Canda on the swine farms.

Remember, contagious goes both ways, swine/bird to human and human to swine/bird. BIG danger on swine farms for true reassortment in pigs naive to this novel H1N1, or in visiting wild ducks among the herds. It has been clearly documented to occur humans to chickens.

Now, that is an awful lot. Get me back on track. Does any of this apply to your topics? If not, please excuse my ramblings.

[mixin]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

It wasn't at all clear that the resistance developed "in" the patient. It just expanded in the patients (like Singapore, were the resistance was present 2-3 days after the start of treatment - too soon for de novo H274Y).

Sequencing showed susceptibility initially and resistance later, so I assumed it developed in the patient.

Are you saying the intitial sequencing could not detect resistance?

Did the Singapore sequence initially show susceptibility and resistance later?

[Mamabird]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

Where was we? Oh yeah.

The 3 elements of influenza evolution.

The mixing bowl and intercontinental transport: the wild mallard and a few other species of intercontinental travel. (Have to not have any immune reaction to influenza, other wise dead birds don't fly very far. Exception, H5 is so pathogenic that even the transport birds seldom complete their migration before mounting some sort of reaction. Remember, with influenza it is not the VIRUS that kills, it is the body's immune reaction that kills the patient.)

The ultimate recipient of interest to us, meaning, us, humans.

The middle man species- swine, domesticated ducks, turkeys, ferrets, chickens, crows, grouse, some pigeons. They have to have both upper respiratory receptors for human and the migrating, mixing bowl species. If not they, the virus selected can not be guaranteed to infect humans. THIS is why we have not had a bird flu, H5, pandemic yet.

Over 460 persons have been infected with H5 thus far but this is due to the heavy innoculum received from long time proximity to the infected domesticated birds & ducks. So heavy is the infection that it has to reach the lower respiratory receptors in sufficient quantity to cause infection.

The same probably occured with some of the H1N1 with the slaughter houses in Mexico and in Canda on the swine farms.

Remember, contagious goes both ways, swine/bird to human and human to swine/bird. BIG danger on swine farms for true reassortment in pigs naive to this novel H1N1, or in visiting wild ducks among the herds. It has been clearly documented to occur humans to chickens.

Now, that is an awful lot. Get me back on track. Does any of this apply to your topics? If not, please excuse my ramblings.

OK, then numerous other viral experts are completely wrong and we do not have much to worry about, unless of course we get additional reassortment in the friendly accommodating pig.

[Mamabird]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

It wasn't at all clear that the resistance developed "in" the patient. It just expanded in the patients (like Singapore, were the resistance was present 2-3 days after the start of treatment - too soon for de novo H274Y).

Are we just making this up as we go along?

Please provide some scientific basis to go along with this novel theory to go along with our continuing spreading and ever more resistant novel virus.

[Snowy Owl]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

Please confer to

US swine flu patients on immunosuppressant drugs develop Tamiflu resistance

Snowy

[mixin]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

Snowy,
About all I got from that blog was this:

But giving them the drugs raises at least the theoretical risk that they will develop and spread antiviral resistant strains of the novel H1N1 flu.

The more we talk about this, the less clear the issue becomes to me. People talk about this like it's a reality but here he calls the risk theoretical. It can't be both.

[Snowy Owl]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

Sorry just got 90 minutes ago the confirmation, you will see confirmation in the next two weeks.

I am uncomfortable because it target specific people again.

Snowy

[HenryN]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

Sequencing showed susceptibility initially and resistance later, so I assumed it developed in the patient.

Are you saying the intitial sequencing could not detect resistance?

Did the Singapore sequence initially show susceptibility and resistance later?

Yes. Singapore was sensitive on May 28 and resistant on May 30.

[Mamabird]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

Snowy,
About all I got from that blog was this:

The more we talk about this, the less clear the issue becomes to me. People talk about this like it's a reality but here he calls the risk theoretical. It can't be both.

There is a ton of evidence from Japan that shows when you take Tamiflu, the target virus soon learns how to wire around the meds and become resistant. This is especially true for children (who normally have immature immune systems) that have been given the drug. Even Roche, the manufacturer of the drug admits to this and even provides a percentage of how often it occurs.

The "new" theory is that the resistance has just been silently hiding in the background all along, and therefore was not previously detectable.

[HenryN]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

Are we just making this up as we go along?

Please provide some scientific basis to go along with this novel theory to go along with our continuing spreading and ever more resistant novel virus.

To distinguish between a de novo mutation instead the selection of a minor population requires some tight collection dates. In Singapore the patient developed symptoms on May 26, was hospitalized on May 27, and was tamiflu sensitive on May 28. Treatment began on May 27 or 28 and collection on May 30 was resistant. The 2-3 period is too short for detection of de novo resistance. The patient was infected with a mixture and the H274Y was obvious (no wild type detected) a few days after the start of Tamiflu treatment.

[sharon sanders]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

I will make one comment. Everyone is aware of the "issue" that we have with Niman and the name of his mapping project.

Also, I have forbid him from using the words "Please" and "Nonsense" to attack other posters.

However, if I see any "Niman baiting" I will impose sanctions on those posters.

Do not mistake a disagreement with Niman for a license to provoke him into displaying "bad behavior".

We are a charity. We are interested in the pursuit of the truth - where ever it takes us.


Thanks everyone for a great discussion!

[mixin]

Re: Two Tamiflu-resistant swine flu cases reported in Washington

...The patient was infected with a mixture ...

What do you mean "a mixture"? Are you saying she had 2 different viral strains at once?