Slashdot Mirror
Seasonal Flu Shots Double Risk of Getting Swine Flu, Says New Study
krou writes "A Canadian study currently under peer review apparently suggests that individuals given seasonal flu shots are twice as likely to get swine flu. The 'perplexing' study has thrown influenza health plans into disarray, with Quebec, Alberta, Saskatchewan, Ontario and Nova Scotia all suspending seasonal flu shots for anyone under 65 years of age. The study appears to be confined to Canada; the US, Britain, and Australia have not reported the same problem, so some are suggesting that the research has 'study bias.' However, the research appears to be 'solid' according to Dr. Ethan Rubinstein, head of adult infectious diseases at the University of Manitoba. 'There are a large number of authors, all of them excellent and credible researchers. And the sample size is very large — 12 or 13 million people taken from the central reporting systems in three provinces.''
Flu shots are for people with weak immune systems and old people that are at higher risk to "die" from it. Never get one done if you don't _need it_. I've see more people almost die due to allergic reactions to shots than i have due to a bad case of the flu.
IF you have health problem, or a weak immunitary system, then you are likely to have had flu shots in the past, AND you are likely to catch swine flu now that a shot for it does not exist yet. So nothing particularly stunning here.
My first program:
Hell Segmentation fault
Don't get vaccinated for multiple strains that are more deadly because it makes you twice as likely to catch only one strain?
I can see several reasons that those who obtain flu vaccines are more likely to contract the swine flu (as well as all the other versions of the flu.) First there's the age issue. The elderly are more likely to obtain a flu vaccine and are a higher risk group to begin with. But you also have the problems of people choosing to obtain the vaccine or not. Those who have never had a problem with the flu aren't likely to vaccinate themselves while those who have are more likely to obtain the vaccination. So in general you would expect those who obtain the vaccine to have more problems with the flu than those who don't.
That said, it's entirely possible the study accounted for all that, but we have no way to know as the study hasn't been published yet . It's only been distributed for peer review at this point.Until the actual methods are available, I consider this just another example of media sensationalism regarding the swine flu.
I did a little googling, and found this via the who's article site: http://repository.searo.who.int/
http://www.ctv.ca/servlet/ArticleNews/story/CTVNews/20090930/h1n1_vaccine/20091001?hub=Health&s_name=
One day after the above article was published.
I think this is the case of the media reporting some scientific findings before it went completely through the peer review process. Sounds like it still isn't decided yet.
This is most likely a case of media hype driving public policy.
I heard a segment on NPR on this. Basically, it's just one study still in the very preliminary stages as studies go. Moreover, thee experts they interviewed said that there was no known biological reason why this would happen.
Given the amount of research into influenza, how to vaccinate against it, and how the bodies immune system responds to these vaccines, I think it's pretty safe to say that there won't be any medical surprises regarding the interaction between two such vaccines.
Until this is vigorously peer reviewed and at least another supporting study by other researchers is done, I call this a definite correlation (which we ALL know does not equal causation....right?).
Please consider the following from the article and the paper:
1) The vast majority of provinces have suspended vaccinations for people not over 65. These provinces likely have several individuals on their health boards with more qualifications than the average SD poster.
2) The sample size was 12 to 13 million people. The paper was written by a large group of very high level names, and the initial peer review results don't involve "sampling bias" or "conditional probability" attacks.
3) The vaccination DOES NOT boost the chances of normal flu, but DOES boosts the chances of swine flu. Accounting for age group and health differences, the trend still remains. People who have gotten vaccinated up to two years ago still show a statistically significant difference in their chance of catching swine flu.
4) Before the bandwagon leaves on the "people who are more likely to get sick are more likely to get vaccinated, accounting for the 100% increase", people who get vaccinations aren't twice as likely to catch flu as people who don't get vaccinations. There's definitely something going on here.
TLDR: This isn't some crackpot study or some anti-vaccination study. They noticed something weird, and like a good pack of scientists, are investigating it.
Signatures are the new names.
"'There are a large number of authors, all of them excellent and credible researchers. "
You do realize, sir, that this really proves little, right? I'd say around 90+% of scientists I know are credible and excellent researchers. We all *want* to do good work and few of us would willingly or knowingly compromise that.
This doesn't stop us from making honest, hard-to-spot mistakes. It's one thing to be sloppy (and that does happen sometimes) or to be dishonest (that also happens, rarely). But in any research, there will be factors you simply didn't know about and, let's be fair, shouldn't be expected to anticipate.
So saying that these are good researchers is, at best, suggesting that you think that they didn't lie or miss something obvious that they should have noticed. At worst, it sounds dangerously like an argument from authority.
This is not necessarily surprising or a new idea. A researcher at Rice University (Michael Deem, whom I have heard speak on this) studies the genetic basis for the vaccine and the resulting efficacy in any given year and there are MANY years in which getting a flu vaccine the previous year will actually increase your chances of getting the flu the next, or make it worse. You can find an interesting calculator here: http://www.mwdeem.rice.edu/pepitope/, where there is also a link to his most important paper on it at the bottom (no registration req.). Here is an excerpt:
Vaccine efficacy can even be negative, however, due to original antigenic sin [7-9], the tendency for antibodies produced in response to exposure to infl uenza vaccine antigens to suppress the creation of new, different antibodies in response to exposure to new versions of the infl uenza virus. The efficacy of the annual in fluenza vaccine, and whether original antigenic sin may occur, depends sensitively on how similar the vaccine and circulating viral strains are. Current state of the art measures of antigenic distance are based on ferret antisera hemagglutinin inhibition assays [10-12], and these distances are assumed to correlate well with vaccine efficacies in humans. However, to our knowledge no such good correlation has ever been shown for an experimental or theoretical measure of antigenic distance.
Ever since I heard this talk, and learned that the flu vaccine is actually a random guess each year, I don't bother with it. I'm young, strong, and tough and very very unlikely to die, I figure.
"sometimes he felt that his whole life was a dream, and he wondered whose it was and whether they were enjoying it."
1. Look up Rhinovirus and Influenza.
2. Notice that they are not the same thing.
Disclaimer: I am not an anti-vaccination nutjob. The following post refers to the flu vaccination, and the flu vaccination only.
First off, with regard to TFA, this alone should not discourage people from getting the flu shot. The simple fact is that the "swine flu" is the same as the "regular flu" that we get every year. It is not particularly more infectious or deadly in any segment of the population than any other flu strain. The fear surrounding this particular strain is simply manufactured by the media. If the flu vaccine reduces the chance of getting the other 15-20 strains of flu by a significant amount, but doubles your risk of this particular strain, you still come out ahead.
However, most people should not even consider getting a flu shot in the first place. If you are between the ages of ~15 and ~60, and are in general good health, you should not get the flu shot. It terrifies me when I see flu shots being given out to students at local schools and colleges. These are the people who have absolutely zero risk of dying from the flu. None. Even if it leads to pneumonia, there is only a risk of death if proper medical treatment is not given. The worst that can happen is, well, that they catch the flu for a week or so.
The flu shot, on the other hand, can be extremely dangerous. My aunt was a nurse, and thus was required by her job to take the flu shot every year. She had been taking them for nearly a decade when, in her mid-thirties, she was paralyzed from the waist down by the side-effects of the flu shot. Had she not taken the shot, the worst that would have happened to her would have been simply getting the flu. She got a large settlement from the vaccine manufacturer and her employer. It was a rather fast process, as they knew beforehand that a certain percentage of people who take the flu shot would have this reaction. The cost of the settlements is simply rolled in to the cost of the vaccine. A couple of years later, a friend of the family suffered similar complications from the flu shot, and died. He was only 28 at the time, and in perfect health. Had he not taken the shot, the worst that would have happened to him would have been simply getting the flu.
The results of this study are interesting, but they make little difference. The vast majority of people should not be getting the flu shot in the first place. Taking it is simply rolling the dice unnecessarily. For those who are very young or old, the risks from the flu shot and the risks from the flu itself start to even out. In that case, the shot may indeed be a better idea. The results of this study do not change that fact.
There is a misconception that being "healthy" will prevent you from getting a primary viral infection, but this is not true. For example if you have never been exposed to varicella-zoster virus (the virus that causes both chicken pox and shingles) and if you inhale viral particles then you WILL come down with chicken pox - I don't care how "healthy" you think you are. Being healthy will, however, usually limit the severe the primary infection.
Being healthy will also allow you to build up a strong specific immune response after exposure to an antigen, so secondary infections by the same or similar viruses can be prevented. As we age and our immunity wanes then the varicella-zoster virus that has been stored in our nervous system for decades will have a chance to erupt again - now you have a case of shingles.
Being "healthy" can prevent a primary bacterial infection, just not a viral one.
If you are young and healthy and think that you don't need the vaccine because you "never get the flu" then you need to realize that you are actually the most likely person in the world to get the flu. Older people are more likely to be resistant to swine flu because many have been exposed before and they carry specific neutralizing antibodies.
So one of the reasons that the conclusion of the article is unlikely to hold up under analysis is that if you've never been exposed to the pandemic H1N1 virus then you are completely vulnerable. Getting the seasonal flu vaccine can't make you any more vulnerable than you already are. Actually I think that the best reason not to draw conclusions from the article is the fact that multiple other countries failed to observe what the Canadians observed.
There is so much paranoia about vaccines that people will seize on any bizarre pseudo-scientific reason not to get one. Unless you are anaphylactic to egg proteins (and I know you aren't) the only non-paranoid reason you should be giving for not getting vaccinated is that you are too lazy and unmotivated, or maybe you have a crippling phobia of needles. Everyone else who gives a different reason is just wearing a tin-foil hat.
This might have something to do with it:
http://en.wikipedia.org/wiki/Original_antigenic_sin
The idea is that if your immune system learns to recognize an antigen similar to, but not sufficiently similar to, the antigen of a new threat, then your body may mount a less effective immune defense against the variant than it already knows. In other words, your body learns to fight seasonal strain of flu, then encounters similar H1N1. Now your body produces antibodies to the original flu, which bind more weakly to H1N1 proteins than an antibody that would have been made especially for H1N1, leading to an overall more severe infection than you otherwise would have had.
~Ben
To me, the most logical explanation is that people who tend to get regular flu vaccines (e.g. teachers, etc.) are generally at higher risk of contracting the flu in the first place due to occupational risk factors, etc.
Kythe
I read up on the syndrome you described because I had never heard of it. It's Guillain-Barré (pronounced ghee-YAN bah-RAY) syndrome (GBS) and seems to manifest after a bacterial or viral infection, which can include a flu shot. Other than that, there's not much else known of the syndrome. For what it's worth, the CDC reports only one of many studies found that around one in one million vaccinated persons may be at risk for developing the syndrome.
Still very interesting. Thanks for pointing this out.
It's not just your health that you effect when you choose not to be vaccinated.
Bruce Perens.