Is H5N1 going to become our new ‘seasonal’ flu, like H1N1 has become since 1918?
If so, what are the implications?
Does it mean that unless you either become infected and survive, or receive a vaccine, you are vulnerable (no natural immunity) each and every ‘season’?
I hope I am very wrong on this, and if this has been discussed before, I apologize.
I think one of the implications is that the decision of which strains to include in the annual vaccine becomes that much more difficult. (Maybe an h5n1 strain is a no-brainer, but it knocks another one out.) Unless we have to line up for two vaccines because they can’t be combined.
The hope is that h5n1 virulence goes down over time so it becomes less important.
JWB – at 08:55
No, JWB, you’re not wrong. I asked this very question at a presentation last spring.
I was told by the epidemiologist that as in all previous pandemics, the new pandemic strain supplants the existing seasonal flu strain and becomes the new seasonal flu strain.
The subsequent few annual flu cycles, according to her, are generally much worse than normal flu seasons.
And yes, the only way to get around it is to get sick and survive or be vaccinated.
This is one reason why I have no illusions that SIP is the holy grail of surviving a pandemic. The threat will linger, and my only hope is that a vaccine is available within one or two years of the official pandemic passing.
I guess my first question should have been “Is H5N1 going to become ANOTHER ‘seasonal’ flu?
JWB. If you assume that H5N1 is going to break through and become etiology behind the next pandemic, then God rest our souls, it will do what H1N1 and the others have done which is become another seasonal flu.
However, if H5N1 does not become a pandemic virus but continues to circulate in pig populations…then it can become either a pandemic virus or a seasonal flu virus through reassortment or recombination with other human or animal viruses.
As far as the direct risk to health goes, as the ripples continue for decades away from the epicenter of the pandemic, the virulence of H5N1 will fall off precipitously. This could also just as easily occur after the first or second or third wave etc…
…there is a mystical component to influenza viruses because they know what they are doing but we…despite our advertised medical knowledge and technical expertise…don’t have a clue!!
The bottom line is that if you can avoid one or two waves in a pandemic, your risk from the virus could be greatly reduced…as historically speaking…virulence wanes over time.
Hope that helps.
Tom DVM – at 10:23
Thanks Tom. Yes, that helps. I was hoping you would jump on this thread. I am a devote reader of you postings. The deeper I look into this, well, you know. :-(
Tom DVM You said, “…as historically speaking…virulence wanes over time. “ Why is that? And with all the surprises so far with this virus, couldn’t it just as easily keep changing in the other direction?
JWB. I am probablly not the one to answer this question but Monotreme is. We will grab him and get him to comment later.
The experts appear to agree that as a highly transmissible virus runs through a population…it becomes more and more difficult to infect people because of rising immunity…so the virus evades the immune system by becoming less virulent and I guess in a sense more transmissible…I guess.
The problem is that some pathogens become less virulent with more passages (one way to produce vaccines) while other organisms become more virulent with more passages.
So like you, I find this less virulence over time argument a bit of a problem scientifically as well.
And there is something else related to this that I totally disagree with…attack rates.
The basis of a pandemic virus is no inherent immunity…none…zero. So if you tell me that 25 % are going to be infected…what protects the other 75%…this makes no sense…
…now, if you tell me 75% are affected and 25 % are not…that makes more sense but I come back to the same question…what stopped the 25% from not being infected.
The point is…once you say this virus is endemic in the world…which the WHO did last winter…then 100% of the population will eventually be infected…it may be ten years after the pandemic but they will be infected.
Thanks.
Tom DVM – at 11:54
Although my expertise is not in this field, my common sense says the same as you about attack rates. Thanks.
Question for Tom DVM and Monotreme:
Most of the concern about H5N1 affecting humans is about it becoming efficiently transmitted from human-to-human.
I rarely hear any concern about it becoming massively more efficient as a zoonotic virus — that is, more efficiently-transmitted from animal-to-person. I have certainly never heard of a previous flu virus becoming a major zoonotic problem (as opposed to an occasional problem as we have seen in several strains since 1997).
Is there truly no reason to be concerned about a possible flu panzoonotic? It doesn’t seem to be on anyone’s radar screen, but my husband and I keep wondering why not.
And while I am obsessing: Is there any evidence that birds and poultry can catch influenza from humans? I keep telling people that once a pandemic starts, it won’t be about the birds any more. But am I right about that?
Thanks in advance —
TomDVM:
You have to believe at least three things about the people who don’t get sick from a virulent virus:
They experienced symptoms so mild they wouldn’t if asked even think they were sick.
They naturally practice social distancing with the same ease as breathing. I see these people from time to time. They don’t mouth breath especially in crowds, they take stairs not elevators, they wash hands frequently and always before meals. I think they were raised with good hygiene habits.
From the earliest recordings there have been people who naturally resisted disease and I think this is the luck of the draw in the genetic pool. Every single scientist who brings up genetics for either catching the flu or avoiding it gets shouted down that they are racist in some manner. Therefore, the findings of genetic links don’t make the news as they should. We hear about specific cells in the throat that encourage H5N1 etc, but I’m guessing that’s a genetic construct. I think this group would more than account for the 25%, not the 75%.
I’ll bet virology becomes the hot new career of the future.
Leo 7. Good to read you again. I think you’re right about virology.
I believe H5N1 is a ‘freak of nature’ and it is difficult to find anything in our collective memory to compare its real menace to but there are a few…
In the animal population distemper is known to previously untouched species…the latest incarnation almost wiped out racoons in Ontario Canada about ten years ago…I have been waiting for it to affect humans but if it ever did, vaccines work (in contrast to influenza vaccines)…
The other example would be smallpox in previously untouched Native North Americans.
In both these instances the survival rates were in the range of 5–15%….
…survival could be due to genetic factors or environmental factors or a combination of both but this 5–15% is pretty consistent across animal and humans under this particular situation.
So I agree with you that there is a natural resistance to infection but it is not 75% as the World Health Organization supposes…it will land somewhere between 5 and 15 percent.
Leo7 – at 14:28 There is only one good possible outcome of this pending nightmare. Once the masses realize that this is THE most important thing in their lives, the amount of money, effort, and most importantly ideas, will be unprecedented.
Let’s hope that the grids stay up and the future viral Einstein doesn’t get wiped out in the first wave. We may just end up defeating more than just H5N1.
TomDVM: I’ve been keeping up with you! You have been surfing the grid!
I’ve come to realize that vaccines may have reached the same terminal point of antibiotics-they’ve been overused in both people and animals. Bacteria and viruses have broken out from this medicinal bandage, and mutated, reassorted and recombined. Even if H5N1 doesn’t jump we will be dealing with major epidemics from reorganized viri and bacteria. My hope is that the concept of public health will return, because its a shame we lost it on the road to progress. I’ve been watching for new antiviral drug development but nothing seems ready to go out to prescription. Sadly, it will take a freak of nature to change the status quo.
JWB: I hope there is a future viral Einstein slaving over a microscope! At this point the only thing that will wake up those who slumber is for the grid to go out and stay out! I know, I’m trying to be more optimistic but read the school thread. It’s depressing.
Leo7 I agree. I should have put in a disclaimer in my last post. “…but I doubt we will have the time.”
JWB at 15:08 “Once the masses realize that this is THE most important thing in their lives, the amount of money, effort, and most importantly ideas, will be unprecedented.” I think the politico hot air will be unprecedented. Money will appear to be approved by Congress but little spent.
I think there is very little the feds can do about a pandemic, but if new vaccine production methods are established that would be a good outcome. The bright ideas about how to do it still have to be there, though. And the private sector must be willing to make the investments, including the manufacturing plants.
In many ways, we’re still on our own.
Bump