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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.
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.
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.
Though it isn't exactly spelled out in TFA, I would _hope_ that their conclusion was drawn after noticing the trend in ordinary / normally healthy people. I think what they mean is, ordinary / healthy people who get the flu shot seem to be twice as likely to contract Swine Flu.
Not a lot of information regarding the study itself is in the TFA, unfortunately. Most of the article just states current and potential ramifications.
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.
In addition to the selection bias already mentioned (people more likely to get the flu are more likely to get flu shots), there's another good reason why it might be that people who didn't get the seasonal flu vaccine are less likely to have gotten the H1N1 flu--that's because they're far more likely to have gotten the regular ("seasonal") flu instead! Turns out that whenever we get a viral illness, our bodies ramp up production of interferons and generally "batten down the hatches" to make us more resistant to viral illnesses in general for a short period of time (weeks) afterwards.
If I'm right, then the powers-that-be in the Canadian health system may be wearing a lot of egg on their faces in the next few months, as the "real" (northern hemisphere) flu season hits. Over time, the unvaccinated people who initially resisted H1N1 because they caught a seasonal flu will once more become fully susceptible to the H1N1 strain as well.
Listen to what I say, not what I mean...
So... which is it? 12.. or 13? Thats a million person difference. Why the hell is this number not solidly reported?
Basically the issue with flu vaccination is this: it's recommended for the elderly and other more-susceptible people, because they have the most to lose if they get influenza. A relatively modest reduction in influenza incidence in this population will save many lives. Young healthy people getting the flu vaccine, unless you are caring for this susceptible population, matters less.
Now, what about H1N1 strain? The elderly actually have some immunity to this strain. Us younger folks have never encountered it before. This is probably why it's mostly younger people falling to H1N1, more so than older folk.
The vaccination recommendation put forth where I live?... Elderly people should get the "regular" seasonal flu vaccine (ie protection against what has always been a great cause of morbidity and mortality in this population), and everyone else should get the H1N1-specific vaccine, because this population is quite susceptible to it. Makes sense, I think.
One mechanism that could account for this is "risky behaviour", which is flu-vaccinated people being less concerned about being in contact with symptomatic people due to their perceived protection through the vaccine. Since the regular flu vaccine does not protect against "swine flu", vaccinated people are more likely to get it. The flip-side being unvaccinated people go out of their way to stay away from symptomatic people, and so are less likely to contract it.
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
In that timeframe, I actually had 3 annual flu shots. Every single time I got the shots, I was ill within about 8 hours and it stayed very sick for about 72 hours.
If a placebo can make you feel better - it strikes me that fear can make you sick.
Or it could be that while you are in line for the shot, somebody else is in line with the misguided idea that vaccines cure instead of prevent and is quietly giving you and the rest of the queue what he thought was just the flu.
I've seen a lot of people come down with the flu after hanging out in a waiting room with a bunch of sneezers. My doc's waiting room now has a sign: "flu-symptoms? Use side door".
Why exactly is that unethical? A double-blind study doesn't mean you have to test on an unsuspecting public. It just means neither the "patients" or the people directly tending to them don't know who got the real vaccine. You can do this with volunteers. What seems unethical is pushing so hard to vaccinate the public *without* doing such a study.
Actually in many cases it's a quite disgusting reality. We have a chain of hospitals locally that have really great TV commercials - they essentially say "If you don't have one of our doctors, you'll fucking DIE". They're really dramatic and obviously designed to instil fear in the audience.
No, the large number of people who dislike the medical establishment should be taken as an indicator of something. Could be anything from bad P.R. to misunderstanding to actual bad practice. Don't rail against these folks, behind such a "movement" there is always some grain of truth.
I think you are onto a good theory there. After all, the body has an end game resource limit, so it tends to put the response where it seems to do the most good. If it perceives an attack by the seasonal version, it quite likely won't react fast enough when H1N1 comes calling.
I found it interesting that us old farts, those of us that managed to survive the 1957 swine flu are said to be less susceptable by a large margin to the current H1N1. I survived it, on a just barely basis I think, the landlady found me buck naked on the bathroom floor where I had passed out after emptying both ends of the system, drug me back to bed, and fed me chicken soup for a couple of days. Chicken soup cures just about anything. ;-) I had been one sick puppy for about 2 days prior to that.
Now 75, and diabetic but otherwise in decent shape for the miles, I haven't gone after the seasonal shot yet, but based on previous exposure to H1N1 giving me some protection from it, I probably will get the seasonal shot in the next week or 2 even if it does raise the risk.
Those old farts reading this that _didn't_ have the 1957 flu would be advised to stock up on canned food and hibernate the rest of the winter, or plan on getting only the H1N1 as early as you can, and the seasonal shot 6 weeks down the road after the first shot has stabilized. H1N1, from my experience with its kin in 1957, is the bigger danger.
But a disclaimer, I'm not a doctor, just a survivor of the original 1957 version and applying Grandpa Gene's common sense. You should apply yours too, its your life.
Cheers, Gene
There was something odd about the Spanish Flu, which was a more deadly version of H1N1. It attacked and killed the healthy and young far more than the sick and the weak, the very young and the elderly.
Now, the report, below says that the two H1N1's are "distant cousins" and "totally not related", but...
The newer "swine flu" H1N1 strain also seems to be following that pattern -- killing teens and "the very healthy" more than the old or young people, in spite of their relative health.
The Spanish Flu made the body attack itself -- the healthier you were, the worse the reaction Click Here:
Main article: 1918 flu pandemic
The Spanish flu, also known as La Gripe Española, or La Pesadilla, was an unusually severe and deadly strain of avian influenza, a viral infectious disease, that killed some 50 million to 100 million people worldwide over about a year in 1918 and 1919. It is thought to be one of the most deadly pandemics in human history. It was caused by the H1N1 type of influenza virus.[4]
The 1918 flu caused an unusual number of deaths, possibly due to it causing a cytokine storm in the body.[5][6] (The current H5N1 bird flu, also an Influenza A virus, has a similar effect.)[7] The Spanish flu virus infected lung cells, leading to overstimulation of the immune system via release of cytokines into the lung tissue. This leads to extensive leukocyte migration towards the lungs, causing destruction of lung tissue and secretion of liquid into the organ. This makes it difficult for the patient to breathe. In contrast to other pandemics, which mostly kill the old and the very young, the 1918 pandemic killed unusual numbers of young adults, which may have been due to their healthy immune systems mounting a too-strong and damaging response to the infection.[2]
The term "Spanish" flu was coined because Spain was at the time the only European country where the press were printing reports of the outbreak, which had killed thousands in the armies fighting World War I. Other countries suppressed the news in order to protect morale.[8]
Perhaps there is something to this study. Now, I don't believe studies as a rule and I have criticized the same, but logic and history seem to add evidence to the *strong* correlation.
As to this study, I think it's a lot closer to being airtight than most (very large sample size, fractional percent margin of error, good science, peer reviews, findings being scrutinized and met with skepticism):
Sadly, I'm not as dubious of this Canadian study as others and will weigh my options for my family.... :-(