Anditbody dependent enhancement and H1N1

[Captain.Sassy]

Hey guys,

I read an article on CBC news this morning that said that new Canadian research had shown a possible link between the seasonal flu vaccine and susceptibility to H1N1. Does anyone know where I might be able to find this research or a summary of it?

THanks in advance for your time and any suggestions!

CS

[Dymanic]

"This is some evidence that has been floated. It hasn't been validated yet, it's very preliminary," cautioned Dr. Don Low, microbiologist-in-chief at Mount Sinai Hospital in Toronto.
http://www.cbc.ca/health/story/2009/09/23/flu-shots-h1n1-seasonal.html

The studies are as yet unpublished, and haven't even completed peer review, so you're not going to find them, but I'd keep these things in mind: The proposed phenomenon has not previously been seen in influenza. The results have not been corroborated. They are not prospective randomized controlled studies (the gold standard of medical evidence).

[Ixion]

As Dymanic said, the studies have not been peer-reviewed nor corroborated, so there will be very little on this finding.

The phenomenon they are speaking of is one that is in the back of scientists' minds when they create a vaccine. The vaccine may stop a particular strain of bug, but it may stimulate the body to help with infection from related strains. It is a common phenomenon with Dengue Fever, which is one reason why no vaccine has been developed to it yet. A virus' goal is to get inside of cells and reproduce to spread. Antibodies made to the virus may neutralize that strain, but bind improperly to related strains and actually enhance those virii getting into cells (thus the term "Enhancing Antibodies" or Antibody_dependent_enhancement).

It has not been noted in influenza, and since the H1N1 vaccine is being hastily produced, long-term studies of that particular vaccine and its effects on overall influenza immunity have not yet been determined.

[Estellea]

ADE also occurred with the 1960's (American?) respiratory syncytial virus vaccine, that was also promptly abandoned. It appears to occur with several viruses with in vitro experiments but as Dymanic said, not observed thus far with influenza viruses although not outside the realm of possibility.

[kellyb]

They've seen it with flu in mice:
http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=236853&blobtype=pdf
Not sure how relevant that is to humans, though.

The CBC article implies that they didn't correct for any confounding factors, so it's not really very informative. Although, the age distribution of those most likely to be infected with H1N1v has made me wonder why teenagers are more susceptible than infants and toddlers. That sort of hints at (to me) a possible antibody mediated enhancement from previous infection with other flus.

[Estellea]

They've seen it with flu in mice:
http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=236853&blobtype=pdf
Not sure how relevant that is to humans, though.I should have delved deeper into the PubMed pages. It can have relevance to humans, ferrets may be better though, and even better would be to collect enough data, with sufficient parameters, on enough humans this upcoming flu season.

The CBC article implies that they didn't correct for any confounding factors, so it's not really very informative. Although, the age distribution of those most likely to be infected with H1N1v has made me wonder why teenagers are more susceptible than infants and toddlers. That sort of hints at (to me) a possible antibody mediated enhancement from previous infection with other flus.It's certainly possible and if the Canadian survey observations are real and it is ADE that is responsible, then their call to cease or delay seasonal vaccination could actually increase H1N1 cases.

[Captain.Sassy]

It's certainly possible and if the Canadian survey observations are real and it is ADE that is responsible, then their call to cease or delay seasonal vaccination could actually increase H1N1 cases.


I thought the article suggested that an ADE mechanism related to seasonal flu (H3N2?) immunity might be increasing the susceptibility to H1N1? So wouldn't ceasing seasonal flu vaccination potentially decrease H1N1 cases?

[Estellea]

Not necessarily Captain and in any event, ceasing or delaying seasonal flu vaccination is a hasty decision. ADE, at least as observed for dengue is most likely facilitated by low antibody:virus ratios, with higher titres neutralising, lower, enhancement. If this observation is a result of ADE, it also has to be determined if heterotypic immunity is responsible.

[Captain.Sassy]

If it's not too much to ask, would you be willing to elaborate on that comment?

[Estellea]

Captain, with dengue, it is not necessarily the presence of heterotypic or cross-reactive antibodies present that facilitates uptake of the virus, but rather how much antibody:virus there is. So when there is a high ratio of antibody:virus, neutralisation occurs; when there is a low ratio of antibody:virus, enhancement occurs.

This, at least in mice, doesn't appear to be the case and cross-reactive antibodies often facilitate viral enhancement for influenza viral strains. This is a simplification based upon a single article and there are other factors involved with protective antibody that need to be considered before pulling the plug on seasonal influenza vaccination you know?

[Skeptic Ginger]

They've seen it with flu in mice:
http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=236853&blobtype=pdf
Not sure how relevant that is to humans, though.

The CBC article implies that they didn't correct for any confounding factors, so it's not really very informative. Although, the age distribution of those most likely to be infected with H1N1v has made me wonder why teenagers are more susceptible than infants and toddlers. That sort of hints at (to me) a possible antibody mediated enhancement from previous infection with other flus.


The enhanced cellular uptake they are referring to is in macrophages. IE the study explains cross immunity, not increased risk of cross infection. So I'm not clear what they mean by the title.Monto and Kendal reported that the frequency of infection, which was determined serologically by hemagglutinin inhibition in persons with high levels of preexisting naturally acquired antibody to N2 NA, was about one-half that of persons without antibody to N2 NA (13). They concluded that antibody against the NA of the influenza virus prevented or modified infection when there was no preexisting anti-H3 HA antibody. We speculate that antibody to NA might also have increased the number of antigenpositive APCs, thereby augmenting activation of influenza A virus-specific T cells....

FcR-bearing cells such as macrophages and B cells are APCs for T lymphocytes (1, 18). It was reported that T-cell responses were enhanced when FcR-bearing APCs were sensitized with antigen in the presence of antibody (4, 12, 20). Macrophages are not permissive for influenza A virus infection, but viral peptides are presented to T cells on the APC surface in association with major histocompatibility complex molecules. Cross-reactive, nonneutralizing antibodies to HA and NA bind to virus strains of other subtypes. This will result in an increase in the number of antigen-positive APCs and augmented activation of influenza virus-specific T cells.The abstract says: "Antibody-dependent enhancement of the uptake of influenza A virus by Fc receptor-bearing cells was analyzed" and the conclusion says "FcR-bearing cells such as macrophages and B cells are APCs for T lymphocytes." Those are immune response cells.


Unless you are talking about HIV where the cell site for initial infection is the immune system cells, this study is not all that relevant to the current unconfirmed observation. If the observation were confirmed, then this study might offer an hypothesis suggesting researchers look at infected cells for some antibody enhanced cell uptake.

Until it is confirmed, however, it is absurd to start worrying the seasonal vaccine is increasing the risk for the new strain. It is the absurd tendency of people to think of vaccines as dangerous. While it is possible, and needs to be checked out, but default position is past vaccination and past infection would produce similar antibodies.

[Skeptic Ginger]

Vaccine and past infection increasing new infection risk should have been seen in populations already. The H1N1 is not infecting the elderly as much as younger age groups. That's the opposite of what you would expect if the hypothesis is correct. The older one is, the more influenza exposure there would be in the population. They should be at greater risk, yet they aren't.

[Skeptic Ginger]

This irresponsible reporting drives me crazy. The news media is so quick to feed the vaccine fears of people it's nuts!

From the articleFour Canadian studies involved about 2,000 people, health officials told CBC News. Researchers found people who had received the seasonal flu vaccine in the past were more likely to get sick with the H1N1 virus.

Vaccine in the past!!!! Well d'uh! That would be all the younger people with flu virus risk factors for more serious disease.

[Skeptic Ginger]

There is nothing on this so far at any of the Ontario Public Health sites where Dr Low works. Sounds like the discussion was about changing the main focus to give the H1N1 vaccine first. Well the drug manufacturers have delayed their seasonal flu vaccine production here in the US and clinics are running out of vaccine. I'm sure the public health in Canada is dealing with the same thing. The news interview might really have been about getting your seasonal vaccine later and the reporter ran with this little side tidbit the Dr carelessly mentioned.

I say careless because he should have known better than to report on unpublished, unreviewed, unconfirmed findings given how the public and the news media react to those very dangerous vaccinations. :rolleyes:

[Skeptic Ginger]

This looks like a great source, BTW: The Ontario Public Health web page (http://www.oahpp.ca/SRI%20Bulletin.php) has a weekly review of the literature that looks to be very thorough.

[Estellea]

There is nothing on this so far at any of the Ontario Public Health sites where Dr Low works. Sounds like the discussion was about changing the main focus to give the H1N1 vaccine first. Well the drug manufacturers have delayed their seasonal flu vaccine production here in the US and clinics are running out of vaccine. I'm sure the public health in Canada is dealing with the same thing. The news interview might really have been about getting your seasonal vaccine later and the reporter ran with this little side tidbit the Dr carelessly mentioned.

I say careless because he should have known better than to report on unpublished, unreviewed, unconfirmed findings given how the public and the news media react to those very dangerous vaccinations. :rolleyes:Yes, but where's the fun in that? Your explanation sounds reasonable although Canada is getting different H1N1 vaccines, at least to some degree, than the U.S. They are based upon the pandemic flu platforms.

[kellyb]

The enhanced cellular uptake they are referring to is in macrophages. IE the study explains cross immunity, not increased risk of cross infection. [/B]

You're misreading. They are talking about non-neutralising antibodies. (bad, infection-enhancing ones.)


In addition,
antibody bound to virus particles can enhance uptake of virus
by FcR-bearing cells, such as antigen-presenting cells (APCs).
This phenomenon, which is called antibody-dependent enhancement
(ADE) of virus infection, has been described for
several viruses, including influenza A virus (3, 6-8, 14, 15, 17,
23).

Ochiai et al. also reported that cross-reactive hemagglutination
inhibition antibodies enhanced infection of influenza A virus
strains within the Hi subtype (15). Experiments using monoclonal
antibodies (MAbs) specific to the HA of influenza A
virus demonstrated that MAbs could be placed into three
groups based on their neutralization (N) and infection-enhancing
(E) activities: group I (N+E+), group II (N+E-), and
group III (N±E+)

[Skeptic Ginger]

Yes, but where's the fun in that? Your explanation sounds reasonable although Canada is getting different H1N1 vaccines, at least to some degree, than the U.S. They are based upon the pandemic flu platforms.While the supply differs because of different buildings, the companies are the same for the most part and acting under the same market forces.

[Skeptic Ginger]

You're misreading. They are talking about non-neutralising antibodies. (bad, infection-enhancing ones.)I didn't misread it. I looked at the significance of the results in the discussion.

The discussion was still about virus entering cells, which is labeled "infection". It is not about how sick an organism gets such as the mice in this case. It's interesting that antibody can facilitate a virus infecting a cell. But there is nothing in this study that suggests vaccines differ from natural infection. There's nothing in that study that suggests we are going to find seasonal flu vaccine makes anyone more susceptible to the 2009 H1N1 than if they were naturally infected without the vaccine.

[kellyb]

I didn't misread it.

Err...so you didn't really mean it when you said :

IE the study explains cross immunity, not increased risk of cross infection.
?

Coz they were talking about traditional infection enhancement from non-neutralizing antibodies as a result of previous flu infections.

Why did you say:

So I'm not clear what they mean by the title.

What is unclear to you? Do you think they were talking about "cross immunity", or non-neutralizing antibodies that cause infection enhancement?

Also, one of your earlier posts said:

Unless you are talking about HIV where the cell site for initial infection is the immune system cells, this study is not all that relevant to the current unconfirmed observation.

You are correct in that this study probably isn't relevant, but not because of anything having to do with HIV's particular affinity for immune system cells. One of the earliest findings in vaccinology was that low titre vaccines can cause disease enhancement. The pioneers of vaccinology saw it with rocky mountain spotted fever and the low titer vaccine. Later it was seen with the RSV vaccine and also the killed measles vaccine. None of these pathogens primarily target immune system cells like HIV does. What's going on is that, any time you have an immune system cell walking up to a virus, but unable to neutralize it, it's set up to become another virus factory. It doesn't have to be HIV. An "enhancement response" can be "primed" for any virus, in theory.

[Eos of the Eons]

An "enhancement response" can be "primed" for any virus, in theory.

Nach. OH, and source for this "theory" besides "cuz I said so"?

[Eos of the Eons]

okay, I can't find out who did the study mentioned in the OP, I just see comments by people about the study. WHO did the study?

Dengue fever causes other infections free entry? However, we know vaccination against one H1N1 virus (already in yearly flu vaccines along with 2 other strains) only primes the immune system against that one strain. Now people are trying to prove it allows free entry for another?

Skeptigirl:
Vaccine and past infection increasing new infection risk should have been seen in populations already. The H1N1 is not infecting the elderly as much as younger age groups. That's the opposite of what you would expect if the hypothesis is correct. The older one is, the more influenza exposure there would be in the population. They should be at greater risk, yet they aren't.

Every year there is an H1N1 strain in the vaccines, just not the pandemic strain until this year's pandemic vaccine to address it. So, if every year this H1N1 and other two covered strain is making people more susceptible to flu bugs, then why aren't flu cases and deaths going up exponentially every year?


There are three types of seasonal influenza – A, B and C. Type A influenza viruses are further typed into subtypes according to different kinds and combinations of virus surface proteins. Among many subtypes of influenza A viruses, currently influenza A(H1N1) and A(H3N2) subtypes are circulating among humans. Influenza viruses circulate in every part of the world. Type C influenza cases occur much less frequently than A and B. That is why only influenza A and B viruses are included in seasonal influenza vaccines.


http://www.who.int/mediacentre/factsheets/fs211/en/

[Eos of the Eons]

From CBC:

Four Canadian studies involved about 2,000 people, health (http://www.naturalnews.com/health.html) officials told CBC News. Researchers found people who had received the seasonal flu vaccine (http://www.naturalnews.com/flu_vaccine.html) in the past were more likely to get sick with the H1N1 (http://www.naturalnews.com/H1N1.html) virus."



All I can find is that quote and people commenting on that quote. No verification of who did the studies and what they were studying and why, and 2000 people is NOT that many! Four studies? By whom??? Who are these "health officials"?

"This is some evidence that has been floated. It hasn't been validated yet, it's very preliminary," cautioned Dr. Don Low, microbiologist-in-chief at Mount Sinai Hospital in Toronto.


So, Low is commenting on how this has been "floated", but there is nothing about his hospital doing the studies.

Who the heck is doing these studies and where can we access them?

Geez. I could send out a press release saying that 10 canadian studies on 500 people are showing that people who get the seasonal flu shot also get cancer, and the inference could be be they get more cancer (cuz older people are the target flu shot audience and my 500 people could all be 90 and all have cancer since 90 year olds are more likely to get cancer than a 20 year old!), and the CBC will eat it up and get opinions on others about my supposed studies to make my studies sound like they were actually done, but there is no evidence of my 5 studies!!


A panel of experts will look at unpublished Canadian data that suggest previous seasonal flu shots may put people at greater risk of catching swine flu, the World Health Organization said Thursday.

The UN health agency has already contacted researchers worldwide to try to corroborate the preliminary Canadian findings, but the effect has not been seen elsewhere, Marie-Paul Keany, WHO's vaccine research director, told a teleconference with reporters from Geneva.

http://ca.news.yahoo.com/s/cbc/090924/canada/canada_saskatchewan_saskatchewan_h1n1_seasonal_flu _suspend_mcmorris

So, people have been getting seasonal shots for years, but this year in Canada the shot won't be offered? Isn't it too late then? Why base your decisions on unpublished studies of only 2000 people overall?

Why not just stop vaccinating? This pandemic only shot, that they will now offer instead of the yearly vaccine, might just be as likely to be found to cause more cases of flu every year then with the way research is done here.

And if a flu strain is coming out of China again this year, as it does every year, then there will be no shot to cover it.
So, do the China strains make us more susceptible to this Mexic strain too then?

Leave it Canada to base policy on Crap!

[Dymanic]

Who the heck is doing these studies and where can we access them?
You can't access them. See my first response to the OP, post #2 to the thread.

[Eos of the Eons]

We can't access them, but Canadians are basing policy on them!!!

Oh, and since our Science and Technology Minister is a chiro, and happy to announce that xtian colleges are getting money...

I have to wonder who did the research!

http://www.edmontonjournal.com/news/Edmonton+Newman+Theological+College+gets/1858550/story.html?id=1858550

Edmonton’s Newman Theological College has been given more than $4 million in federal funding for expansion projects that include a new research library and additional classrooms.
The college will also be able to build a video conference centre with the money, which was announced Monday by Edmonton-Leduc MP James Rajotte, on behalf of the federal minister of state for science and technology, Gary Goodyear.

Yeah, so let's the world in antivaccine rhetoric too! Gotta love where our funding dollars go in this country.

Just Thursday I signed a document stating that I indeed am not Roman Catholic, so my tax dollars won't be designated to the Catholic school. It's a Canadian law that Roman Catholics must have their tax dollars allocated to Catholic schools. It's a LAW. It said so on the form I signed!



That individuals who are Roman Catholic must direct their taxes in support of schools to the Roman Catholic separate school district. A Roman Catholic is defined as an individual who recognizes the Pope as head of the Church (i.e. Roman Catholic, Greek Catholic, Ukrainian Catholic).


http://education.alberta.ca/media/305739/revised_form_6a.pdf

Canada sucks, and so does our non-peer reviewed "research".

[Eos of the Eons]

Funny how published research never makes headlines:
http://news.bio-medicine.org/medicine-news-2/Annual-vaccination-against-influenza-associated-with-decreased-risk-of-death-in-elderly-2021-1/


A study from the Netherlands suggests that elderly persons who receive a yearly influenza vaccination have reduced risk of death from all causes, according to a study in the November 3 issue of JAMA.

Natural news won't be headlining this kind of research either, unlike the spin they were too happy to put on the unpublished research that can't actually be looked at to verify anything.

[Dymanic]

We can't access them, but Canadians are basing policy on them!!!I could be wrong, but the impression I got when I first heard that there was talk about suspending the seasonal vaccination campaign in Canada was that the thinking behind it had more to do with the pandemic strain being expected to continue to dominate over the seasonal strains. I could see the logic: why bother dedicating resources to vaccinating against strains that are likely to barely make an appearance (if at all), just because you can -- especially considering that doing so will probably serve to reinforce the decision a lot of people seem to be making to go for the seasonal vax and skip the pandemic vax, even though the best bet would be to do it the other way around?

I dunno. I can't figure Americans, much less Canadians.

[Eos of the Eons]

The impression I get from the news articles everyone is bleating about is that the pandemic vaccine is untested and will contain cancer causing toxins, so don't get it. Now the annual flu vaccine will hinder your immune system and make you more likelty to get the pandemic vaccine. So, don't get either. Vaccines are all bad.

Especially don't offer something that is going to weaken the immune system against the main strain!

http://www.thestar.com/news/canada/article/701433


It did so partly in response to preliminary Canadian research that suggests a seasonal flu shot may increase the risk of catching the H1N1 virus. The research has not yet been published or independently validated through peer review.



CTV Ottawa has learned the Ontario government will only vaccinate those 65 years and older for the seasonal flu this year.


http://ottawa.ctv.ca/servlet/an/local/CTVNews/20090923/OTT_Swine_McGuinty_090923/20090923/?hub=OttawaHome



In an interview with The Associated Press, Fukuda warned about the potential dangers of untested vaccines, although he stopped short of criticizing Europe's approach outright.
http://www.cbc.ca/health/story/2009/07/27/swine-flu-vaccine.html

Our news media seems to be completely incapable of reporting the fact that the pandemic vaccine is tested, since it is the same vaccine used every year, tested every year, just with a different strain of virus.

Our news media panders to the altie viewpoint, they might as well just ask astrologers about space missions!!

Canada is now a leader on basing policy on crap. We Canadians have no choice but to listen to it and not have any other viewpoint on it. We also have no choice but to think the vaccines are unsafe and untested and a really stupid idea.

[Skeptic Ginger]

I could be wrong, but the impression I got when I first heard that there was talk about suspending the seasonal vaccination campaign in Canada....It varies by province. Even the Canadian public health officials are not in agreement on this.

[Eos of the Eons]

It varies by province. Even the Canadian public health officials are not in agreement on this. It is because of our politics. Check out what party is leading what province and you'll get a clear picture. Our conservatives lead the federal gov't and Alberta. Here is more about what they are up to in Alberta:


http://www.edmontonjournal.com/health/health+hotseat/1898527/story.html

We can thank the conservatives and their elected woo woos for this current mess. Politics always trumps science. BC is a crazy too, but their policies are supported by the current feds. Very anti-science.

[Captain.Sassy]

I could be wrong, but the impression I got when I first heard that there was talk about suspending the seasonal vaccination campaign in Canada was that the thinking behind it had more to do with the pandemic strain being expected to continue to dominate over the seasonal strains.

Yup, this is indeed the case from what I know.

I don't think anyone in PHAC is basing policy on the preliminary findings of the study. They just mentioned it in the article.

[Eos of the Eons]

Yup, this is indeed the case from what I know.

I don't think anyone in PHAC is basing policy on the preliminary findings of the study. They just mentioned it in the article.
Just for the delight of antivaxxers? The policy makers are quoted as saying they did base their decisions partly on the research. This dissappoints me immensely, as does any mention of crappy non-peer reviewed unreplicated "research".

[Skeptic Ginger]

This little paragraph in the Branswell authored news report on this subject (http://www.google.com/hostednews/canadianpress/article/ALeqM5g-jBo3N9xWt8pxrXRQvzljFetL0g) seems to be getting very little attention:The link, if real, is to mild disease. One person who has seen the study says it seems to suggest that those who got a seasonal flu shot were less likely to develop severe disease if they became infected than those who hadn't received the shot.

[Captain.Sassy]

Just for the delight of antivaxxers? The policy makers are quoted as saying they did base their decisions partly on the research. This dissappoints me immensely, as does any mention of crappy non-peer reviewed unreplicated "research".

Could be, but that wasn't my interpretation of that article.

Skeptigirl's article certainly seems to suggest that provincial public health agencies actually are basing their seasonal flu vaccine decisions at least in part on the study's findings. But I think I heard something about rolling back the seasonal flu vaccine, in Ontario, before this study, because pandemic H1N1 was supposed to be the dominant virus.

Anyone think they'll have the vaccine out in time?

[Eos of the Eons]

Though few people appear to have seen the data, word of the findings has spread like ripples in a pond in recent weeks.

Ontario announced it would vaccinate seniors against seasonal flu in October, but delay the bulk of its seasonal program until later in the winter. Saskatchewan said it may cancel its seasonal campaign altogether. And Manitoba said it is planning for the seasonal program to run as scheduled, but building in the capacity to change course if need be.

Oh yeah, they are not basing policy on this ridonculous "research" at all. *rolls eyes*

If anything it seems people who haven't seen it are putting their own spin on it and ignoring even what you quoted.

Is this an excuse to cheap out on not providing the regular shot, I mean we are to now ignore anything coming at us from China and pretend other flu strains don't exist or at the very least won't infect/affect anyone under 65.


Complicating the issue is the fact that scientists elsewhere have looked for a similar effect but have failed to see it. The U.S. Centers for Disease Control has said it finds no evidence of this and Kieny said British and Australian researchers have also drawn a blank when they searched their data.


Oh gee, we're starting to see evidence that the research is not replicable.

[Kuko 4000]

SBM just posted this:

http://www.sciencebasedmedicine.org/?p=1940#more-1940

[Skeptic Ginger]

Anyone think they'll have the vaccine out in time?No, we won't. The 2009H1N1 is already circulating widely and most of our vaccine is not yet ready.

Apparently Australia just started their vaccine program. Ours is supposed to start mid-October and Canada reports planning on starting in November.

[sol invictus]

A “perplexing” Canadian study linking H1N1 to seasonal flu shots is throwing national influenza plans into disarray and testing public faith in the government agencies responsible for protecting the nation's health.

Distributed for peer review last week, the study confounded infectious-disease experts in suggesting that people vaccinated against seasonal flu are twice as likely to catch swine flu.

<snip>

Met with intense early skepticism both in Canada and abroad, the paper has since convinced several provincial health agencies to announce hasty suspensions of seasonal flu vaccinations, long-held fixtures of public-health planning.

<snip>

“There are a large number of authors, all of them excellent and credible researchers,” he said. “And the sample size is very large – 12 or 13 million people taken from the central reporting systems in three provinces. The research is solid.”

http://www.theglobeandmail.com/news/technology/science/study-prompts-provinces-to-rethink-flu-p%3E%20lan/article1303330/

It hasn't completed peer review, but if several provinces have suspended flu shots they're clearly taking it very seriously.

So how could it be that a flu vaccine raises the risk for another strain? The obvious guess is bias (for example that those getting the vaccine are weaker on average and therefore at higher risk for any other disease, including swine flu), but surely that was controlled for in the study, and with 12-13 million patients the statistics should be excellent.

Comments?

[Dymanic]

There's a thread on it already:

http://forums.randi.org/showthread.php?t=154778

[Skeptic Ginger]

http://www.theglobeandmail.com/news/technology/science/study-prompts-provinces-to-rethink-flu-p%3E%20lan/article1303330/

It hasn't completed peer review, but if several provinces have suspended flu shots they're clearly taking it very seriously.

So how could it be that a flu vaccine raises the risk for another strain? The obvious guess is bias (for example that those getting the vaccine are weaker on average and therefore at higher risk for any other disease, including swine flu), but surely that was controlled for in the study, and with 12-13 million patients the statistics should be excellent.

Comments?From your link:Met with intense early skepticism both in Canada and abroad, the paper has since convinced several provincial health agencies to announce hasty suspensions of seasonal flu vaccinations, long-held fixtures of public-health planning.This is false. Those provincial health agencies have not seen the paper either. They are merely acting on the news leak, as far as I know.

Also:“There are a large number of authors, all of them excellent and credible researchers,” he said. “And the sample size is very large – 12 or 13 million people taken from the central reporting systems in three provinces. The research is solid.”This is misleading since the number of flu cases they are talking about here is only a couple thousand. I don't think Canada has had even a million cases of 2009H1N1.


And this statement is an outright falsehood as well:The vaccine suspensions do not apply for people over 65. Seniors are considered more susceptible to severe seasonal flu symptoms. At the same time, they carry antibodies from a 1957 pandemic that seem to neutralize the current version of H1N1.There's no way that has been established.


That's particularly piss-poor reporting.

[Eos of the Eons]

My province is thankfully saying they looked at all available information and are finding the stupid study wanting. yay!!! We get both shots if we want them!


Canada's chief public health officer, Dr. David Butler-Jones, said Wednesday there appears to be no increased risk of severe disease from the H1N1 virus among people who received seasonal flu shots.
"Those who have severe disease have the same rate of having been immunized with seasonal vaccine as the general population," Butler-Jones said. "So the seasonal vaccine is not a contributor or a cause of severe disease or illness in those people."
He hypothesized that people who got seasonal flu shots may have been more likely to go to their doctor to get tested for H1N1.

http://www.cbc.ca/canada/edmonton/story/2009/10/01/calgary-swine-flu-h1n1-clinics.html
Other countries are reporting contradictory evidence too.

[Skeptic Ginger]

From Flutracker today: (http://flutracker.rhizalabs.com/)

Suspected Cases: 239
Confirmed Cases: 9810
Fatal Cases: 46
This is an aggregate data point for Canada. So if the sample size from the study was "large – 12 or 13 million" taken from only 3 provinces, and Canada has 12 provinces, then you might have a few thousand flu cases in that sample. Actually that is consistent with an earlier news article by Branswell that said a couple thousand flu cases were in the study sample.

Those cases would be the more severe and/or the ones who sought medical care. We quit confirming mild cases a while ago and I'm sure Canada did the same. So the researchers would have to have a large enough sample to rule out the fact that people who got the flu vaccine last year who were under age 65 may have a disproportionate number of people at increased risk of flu for some reason. Either they were more likely to show up for care if infected, or they were more likely to be infected such as daycare workers and kids in daycare, teachers, health care workers, and so on.

And on top of all this there was that little mentioned fact I noted that while being more likely to get infected, one was also more likely to have milder disease.



I should also add a bit of the politics here regarding Canadian health care decisions to delay seasonal flu vaccines. There is also a delay in production of seasonal flu vaccine. How convenient to now have a reason to delay some of the vaccinations.

[sol invictus]

There's a thread on it already:

http://forums.randi.org/showthread.php?t=154778

Sorry about that - I ran a search for "swine flu" in thread titles and missed this one.

Anyway it sounds like the study is probably wrong, and it is in fact a selection effect. It must be really difficult to be an epidemiologist, there are so many confounding factors to control for...