Aug 17 2009

H1N1 Vaccine and GBS

As most people have probably heard by now, we are in the midst of a pandemic – swine flu or H1N1. This is a strain of the Influenza A virus, which causes a severe respiratory infection. The virus evolves rapidly and each year new strains appear, causing the annual flu season which causes 30,000 deaths in the US and 500,000 world wide.  (The H and N refer to the two main proteins used to classify different strains of the virus – I wrote a more detailed summary here.)

Because the current pandemic is being caused by an H1N1 strain, the same strain that caused the 1918-1919 pandemic that killed millions, world health organizations are understandably concerned and they are tracking it carefully. There are also efforts underway to develop a vaccine. This further raises concerns because of the 1976 H1N1 pandemic – the vaccine given for that strain was linked to cases of Guillain-Barré Syndrome – GBS. Unfortunately, while the likely risk of GBS is much smaller than the risk from the flu itself, this risk has stoked the flames of fear-mongering about vaccines. This somewhat irresponsible article in the Daily Mail is a good example.


GBS is an autoimmune neurological disorder. It is a monophasic (one time process that gets worse then gets better) post-infectious illness. Essentially, an infection with a virus or bacteria triggers the immune system to have a second inflammatory response against myelin proteins. Myelin is the insulation around nerves – the inflammation inhibits nerve conduction, damages the myelin, and when severe can damage the underlying nerve fiber itself. This results in weakness, numbness, and autonomic dysfunction. The weakness, when very severe, can inhibit breathing resulting in the need for mechanical ventilation. Right now the greatest risk from the disease is the autonomic dysfunction which can cause a severe drop in blood pressure, among other symptoms.

If recognized early and treated properly, most patients with GBS have a short illness – days to weeks – and recover nearly fully. However, severe or untreated cases can result in permanent paralysis and there is a 3-4% death rate. (Although I have treated many cases, I have never seen a death from GBS – not even close. I suspect these cases result from a significant delay in treatment or improper treatment.)

GBS can not only be triggered by the flu or other infections, but also by vaccines used to prevent infections. This is because vaccines are designed to stimulate the immune system, to provoke an immune response – which is what causes GBS. The risk of getting GBS from the flu vaccine is about 1 in a million. This is very reliable data, as we have been using the same basic technology for the flu vaccine for decades and we have reliable statistics on GBS as treatment requires hospitalization. Some cases may be missed if they are very mild (probably rare, but also if a case is too mild to be recognized then who cares) or from misdiagnosis (also probably rare as it is fairly easy to eventually confirm the diagnosis even if it may be difficult initially).

Of note, GBS does not affect the brain (as the Daily Mail incorrectly reported) but only the peripheral nerves. Occasionally the spinal cord may also be affected, but generally speaking GBS is a peripheral disease.

H1N1 Flu Vaccine

As we gear up for the H1N1 flu vaccine there is much fear-mongering among the antivaccinationists, the usual conspiracy theorists and critics (usually competitors) with science-based medicine. The Daily Mail piece, unfortunately, plays into this fear mongering while burying any reasonable responses from scientists deep within the article. The reason the GBS concern is raised is because in 1976 the H1N1 or swine flu vaccine triggered a GBS outbreak, and it is estimated that about 10 in a million recipients came down with GBS. It also turns out that the 1976 pandemic fizzled, and turned out to be very mild.

The flu vaccine uses the same basic technology that has been used for decades, and therefore it is very reliable and the risks are fairly well known. Each year the vaccine has to be tweaked to target the likely strains of Influenza A that will be prominent that year. So the risks from the vaccine may vary slightly as new strains are being targeted, but over the last 30 years since the 1976 episode the risk of GBS has been steady at about 1 in a million – far less than the risk of the flu itself.

Therefore the accusation that the upcoming H1N1 flu vaccine is untested is not a fair or accurate statement. It is highly tested. But it is true that the particular strains targeted will be new. Some charge that therefore vaccinating the public will amount to a large “guinea pig” experiment. This is a naive and misleading statement, however. The fact is that every single medical intervention, every new drug on the market, is in the same situation. Even if we highly test a new drug or treatment in thousands of subjects, it may be marketed to millions. We cannot possibly know the statistical effects on millions of people until it happens. There is therefore nothing different about the H1N1 vaccine from any other mass medical intervention.

If anything, our experience is even greater because we have decades of experience vaccinating millions of people with very similar vaccines.

Even still, it makes sense to track new interventions  – to gather data about what happens when millions are treated. For that reason the British National Health Service has apparently asked neurologists to report new cases of GBS starting this summer. They want to establish a baseline rate of GBS using this reporting system so that if there is a spike of GBS following the H1N1 flu vaccine they will pick it up quickly and can make recommendations about whether or not to continue the vaccine or abort it. This makes sense.

But the Daily Mail is using this precautionary measure to scaremonger about the safety of the vaccine. This is like using the presence of seat-belts in cars to scaremonger about their safety.


The upcoming H1N1 vaccine is simply the regular flu vaccine targeted against the H1N1 proteins to cover the current pandemic strain. Because the pandemic will likely come in two waves, and we are between them right now, this gives us the opportunity to create a vaccine specific for the pandemic strain – rather than guessing, as we do each year for the regular flu season. We have a great deal of information about the safety of this vaccine, but it is always reasonable to track safety going forward. We also have a lot of information about the effectiveness of the flu vaccine – it is very effective. The vaccine itself is very effective, but the actual effectiveness each year varies from 60-80% depending upon whether or not the proper strains were targeted.

The risk of GBS from the flu vaccine has been around 1 in a million – a very rare complication. The risk may not be any higher for the H1N1 vaccine. It is actually not known why the 1976 vaccine had a higher rate of GBS, but it has not been repeated in the last 30 years. Perhaps there is something about H1N1 that increases the risk of GBS, and for this reason monitoring GBS as the vaccine is administered is reasonable. So far, in preliminary tests of thousands of individuals with the new vaccine there has not been any increased risk of GBS, but this process in ongoing.

There are no absolute guarantees in medicine – but the best evidence we have to date strongly suggests that the risk of the H1N1 flu is likely to be much greater than the risk of the vaccine itself. And the usual safety measures and testing are in place – in fact there is heightened safety monitoring. Medicine is a risk vs benefit assessment. But it is easy to fear monger by focusing only on the risk.

71 responses so far

71 thoughts on “H1N1 Vaccine and GBS”

  1. prunesrule says:

    Great article as always Steve. Living in the UK we do get sensationalist stories like this often. but it is in the daily mail, so I doubt their readership will make it past the headline and the pictures since it is not about Diana or immigration!

    Unfortunately this reason alone does not make the article wrong (a kind of anti-argument for authority) it is misleading, and I am glad we have people who understand what goes on to tell us the science behind these articles. I did feel compelled to leave a comment which may likely be moderated out, although I simply presented the science in a an eloquent way, this may be where the Mail falls down.

    When arguing against anti-vac people here in the UK blogs like this help provide information to answer their wild claims

  2. Jim Shaver says:

    Stoking public fear about the H1N1 flu vaccine, intentionally or otherwise, through sloppy, sensationalistic, scientifically weak, and poorly researched articles is journalistically substandard (or worse). Science and health writers for major publications have no excuses for such mediocrity. (The old phrase “yellow journalism” comes to mind.)

    However, I do understand the average person’s gut reaction and angst towards the idea that getting a shot that is supposed to protect him from infection has a small chance of triggering a serious reaction and illness. A person who gets GBS after receiving a vaccination when he was otherwise healthy is sure to regret that decision; the fact that his case represents a huge statistical minority does little to console him. If only he hadn’t let them give him that shot, he would be fine.

    I think this very natural fear of making what turns out to be a “bad decision” for oneself is what sustains much of the anti-vaccination movement. It’s like a reverse lottery, and we know how bad people are generally at understanding lottery odds when it comes to spending their hard-earned money.

    I can’t stand the vocal anti-science crowd any more than the average skeptic. But I wonder how or if we can ever get past that instinct we all have to weigh the risk of doing something to ourselves more heavily than we weigh the risk of doing nothing.

  3. superdave says:

    Thanks for this post as it clears up some confusion I had about what you said in the podcast. Also, is there any chance now that people won’t see that these autism advocates are simply anti vaccine now that they are protesting both gardisil and the H1N1 vaccine? Neither of these vaccines have any implications for childhood autism yet they vehemently oppose them. I think it is because if they can somehow prove that if any particular vaccine is dangerous it validates their conclusions that the MMR and other childhood vaccines are dangerous too.

  4. That is a good point – people do naturally fear causing harm more than they fear not preventing harm.

    That is why it is best to frame options in terms of risk – what is the risk of being vaccinated vs the risk of not being vaccinated.

  5. Joe B says:

    Daily Mail article says 40million vaccinated. 25 deaths, 500 GBS cases

    So that would be a 1 in 1.6million chance of dying from GBS from the vaccine and a 1 in 800,000 chance of GBS if the exact same vaccine was used.

    According to this:
    The odds of being hit by lightning are 1 in 700,000.

    So even if swine flu vaccines haven’t gotten any safer in 35 years, you are more likely to be hit by lightning than develop GBS from getting a swine flu vaccine.

    The USA Today story also puts a lightning strike as 4 times deadlier than GBS.

  6. artfulD says:

    What are the odds of dying from either GBS or swine flu if you don’t get vaccinated, that’s the real question.

  7. superdave says:

    It’s not that simple artfuld, getting vaccinated also makes you less likely to give the disease to someone who may be more vulnerable than you.

  8. artfulD says:

    Except that death has a way of conferring other vulnerabilities to one’s survivors and/or dependents.

  9. tmac57 says:

    “Except that death has a way of conferring other vulnerabilities to one’s survivors and/or dependents.”
    This is not an equivalent situation ,( if you are being serious) since one person becoming infected with the flu can exponentially spread it to countless numbers of people, not just a handful of relatives.

  10. dwayne says:

    “Therefore the accusation that the upcoming H1N1 flu vaccine is untested is not a fair or accurate statement.”

    Wanna know another thing that’s untested? NOT using the upcoming H1N1 flu vaccine against this season’s virus.

    (Yeah, I know, Shaver stole my thunder in a more eloquent way.)

  11. artfulD says:

    And who, if they are “exponentially” vulnerable, have more than just ourselves to be wary of such contact.

    And thus also having good reason to know what the odds are of any of them, relative or stranger, of dying from the above mentioned effects of vaccine compared to the present odds of dying from the disease itself.

    And as an aside, when we realistically consider the consequences of dying, we factor in or weigh the consequential fates of our relatives to a much greater extent than that of our neighbors.
    Whether or not that there’s anything wrong with that.

  12. tmac57 says:

    Looking at this site: (Flu Math), the author comes up with the odds of dying from the flu vs from the vaccine at about 80 to 1, and that was using conservative assertions. The potential variables make certainty impossible, but reasonable probabilities can be extrapolated from what we historically know about the disease and vaccine risk factors.

  13. alcareru says:

    Thanks for yet another great article. There aren’t nearly enough qualified people taking on this kind of hysteria.

    I wonder about the future of humanity when such nonsense can so easily propagate itself around the intertubes. At this rate we’ll end up back in the dark ages with praying, magic water and shamen waving their hands around instead of modern medicine.

  14. tmac57 says:

    alcareru-“…and shamen waving their hands around instead of modern medicine.” See: Therapeutic touch.

  15. s says:

    Well GBS is not the only risk, there is also the risk of other autoimmune disorders due to the “adjuvants”. So “afludiary” is not wholly correct. The question is of course if individuals having adverse vaccination reactions are the same that would get most ill from an infection?

    See my short comment in the “August Is Vaccine Awareness Month – Who Knew?” for some refs.

  16. s says:

    A small point of note the 1976 swine flu (A/New Jersey/76 (Hsw1N1)) *never* spread outside Fort Dix. So there was *never* a “1976 H1N1 pandemic”.

    In fact there was no influenza pandemic what so ever that year.

    This is concisely told on This Week in Virology #43 starting at about minute 31 by virology professor Vincent Racaniello (Virology Blog).

    Vincents “boss” at the time has also written shortly about 20th century pandemics and his role in the Fort Dix decisions (glossed over I’d say) on

  17. gflavius says:

    The author misses the point.
    GBS is not the major issue with the “swine-flu” vaccine.
    Try discounting the detailed and documented evidences in Jane Burgermiester’s legal injunction against Baxter in Austria.
    Good luck.

  18. cdnintel says:

    This is neither the time for fear mongering OR judging others.
    It is time to realize there are more important things occurring that deserve – at the very least – an open mind and the willingness to put in the time to decisively research real-world information prior to jumping to conclusions. This is not a “game”; in fact, this time it is much, much more. This is not simply about science, influenza or illness. It is broad in it’s scope, geopolitical, economic, our world is quite possibly about to change in a manner we could not even dream of in our worst nightmares. Please read on. I am not interested in battling with colleagues or inciting fear, but rather suggesting that each one of you conduct some research of your own if you are unaware of the serious ramifications of what is occurring all around us.

    The Novel H1N1 influenza originally released in an area just southof Mexico City, MX and which has subsequently spread to virtually all areas of the planet is absolutely laboratory developed. This is a weaponized virus. Conclusive independent research has proven to us that this strain is a “triple triple recombinant”, meaning that it is virtually impossible to develop naturally. Six to eight percent of viral DNA does not match with ANY VIRAL DATABASES and Blast Analysis of genetic codons done primarily by Alexander S. Jones and a team of virologists has proven this is an engineered virus with genes from four different sources of flu from three different continents, “ground zero” being just south of Baxter Laboratory facilities in Mexico City. Further, this influenza is almost positively a “bridge virus” (able to become much more lethal). It has, and will continue to recombine into more lethal recombinants that include the more lethal genes found in H5N1 (Avian Flu). In the next few weeks, its effect is going to become much more serious with the expectation being that it will become extremely serious. In fact, information in the public domain suggests repeatedly that this situation (or situations) are already extremely serious. If nothing else, the wide variation in information is enough to bring one to question what is going on here.

    While to date the Western nations have avoided confirming the inevitable and upcoming vaccinations to be mandatory, it is extremely important to note/understand that a plan was put in place in 2005 by ALL Western Nations (this does not preclude Eastern/Asian/European nations) to hand authority to the World Health Organization (W.H.O.) in order to implement MILITARY and MEDICAL Martial Law and to ENFORCE MANDATORY VACCINES, the latter of which includes authority to seize property in order to place people in civil detention camps if they refuse to be vaccinated. This is but ONE example of numerous possibilities that governments have suggested – again – in the public domain. Please note that much of this information becomes available in the public domain daily. I have in my possession documents from both public and inside secret sources that prove much of this with no doubt.

    Within the last 72 hours, France has publicly declared that – citing and in keeping with the treaty with the W.H.O. – beginning in September the country will convert to “Military Rule” (martial law, etc.). Numerous other threats upon the people of various nations have been forthcoming in recent days to ensure that all nationals submit to mandatory vaccinations. The importance of this lies in the understanding that the vaccinations themselves are to contain (Pharmaceutical companies such as GlaxoSmithKline, any many others admit) adjuvents that are widely known on a scientific and medical basis to be extremely toxic to humans. Such components of these vaccines, specifically, will be Squalene (extremely toxic when introduced into living organism) as well as toxic doses of mercury compounds to name just two. It is widely believed by a wide cross-section of doctors, virologists, military personnel and others too numerous to mention that the end-game scenario is literally to cull, or reduce the population of the earth. Research suggests that the PTB (“Powers That Be”) hope to end the lives of approximately five billion persons through this worldwide initiative. If you believe there are individuals in our midst that would (supposedly) fly large aircraft full of innocent people into buildings killing thousands on U.S. soil, why is it so far a stretch to entertain the possibility that there are equally sinister individuals on our planet with even greater sinister goals?

    While it is extremely common for the majority of individuals to respond to such a suggestion as absolutely preposterous, again, there is substantial well-developed information in the public domain to suggest this has been a plan in the making for many many years. Please do not hesitate to research this information I am providing yourself rather than dismissing it as ludicrous. WE ARE FACING THE MOST CRITICAL TIME ON EARTH THAT HUMANS HAVE FACED IN THE HISTORY OF MANKIND. This is but an introduction to the lengthy and evil situation occurring around the world right now. Again, it is IMPERATIVE that you research the preceding information yourself and ultimately inform others in your neighborhoods, cities, states, families, friends, associates, etc. and urge them to do so as well. Then PROTECT YOURSELVES (see research suggestions below to start). This is not a joke. Research. May all the protection of life attend you! TBB –

    Research Notes: Health- Vaccine ALTERNATIVES : Dr. John Waterman (U.S.A.) (Highly recommended)

    Military and Geopolitical Facts and much more: Dr. Bill (William) Deagle (U.S.A.) (Highly recommended) – Please research Dr. Deagle’s background as well.

    More information on a variety of pertinent studies:
    Dr. True Otte, ND, PhD
    Dr. Alexander S. Jones, Computer Technologist/Virus Expert
    Dr. Mayor Eisenstein, Chicago, Illinois Author “Don’t Vaccinate Until You Educate”
    Dr. R. Blaylock, CCN, Researcher of indigent components, mandatory vaccinations to occur this fall with total lack of testing (quote from July, 2009).

    I have provided you with some keys, it is up to you to insert them and open the doors.

  19. keithgw says:

    Unfortunately, the human mind does not intuitively understand statistics. Rather, we are more easily persuaded by human interest stories and appeals to emotion. Is there a way to frame this argument in kind? Can we find a way to present this argument with an appeal to emotion? To me this seems an alternate and effective way to convince those who are antivax. It is not evidence and statistics that convinced them that vaccines are bad, it is the appeal to emotion – that MMR vaccines are falsely implied in autism and that the flu vaccine causes GBS. The above article goes a long way to convince me and other like-minded skeptics, but we need to find a way to present this information to the antivax community in a way that resonates with them. Any ideas?

  20. neurobsn says:

    I am a survivor of Guillain-Barre Syndrome. I had Guillain-Barre when I was 12 years-old (1992). I was on a ventilator. I remained hospitalized for a month. I had to learn how to walk again, which took me a year of physical and occupational therapy. Though the physicians were not for certain, they did seem to think that GBS may have been caused by a viral illness and a recent flu shot. Because of this information, I have been instructed not to receive the yearly flu shot.

    I have residuals from GBS. These include loss of sensation (hot/cold and sharp/dull) from my finger tips to my elbows and from toes to my knees. Neuropathy (tingling sensation) in my extremities as well. I have also been diagnosed with autoimmune hypothyroidism and polycystic ovarian disease. My endocrinologist thinks there is a link between GBS and these disorders as they are both autoimmune and so is GBS. This has caused trouble with my metabolism, my weight, and my reproductive abilities. I also have muscle and nerve loss.

    I am now a nurse and work in clinical research for pediatric brain tumors. Being a medical provider that deals with patients from all over the world, I am pretty certain the H1N1 vaccine will be a requirement.

    I am worried about receiving the vaccine as I have already dealt with GBS. It is horrible. I wouldn’t wish it on anyone. I was given an 82% chance that I would not survive it when I was 12.

    I have two children and worry that them receiving the vaccination could result in GBS. I am even hesitant to give them the regular flu vaccine. My now four year old received the flu mist vaccine last year, but I was even afraid of the consequences from that.

    I know that there are those people who are extremists and do do not vaccinate their children. I do vaccinate, but just not the flu shot. I will also not vaccinate for meningitis due to the risk of GBS that has been well published. Having been there and speaking from experience, there is still a fear for me. It is a justified fear. I hope people can understand where I am coming from.

    I do think getting the flu shot and the H1N1 vaccine is a personal choice. I also think people should make an informed decision for themselves and their family.

  21. neurobsn – sorry to hear about your GBS. However, your case highlights the risk of basing decisions on very limited experience, rather than statistical data. We all find our own personal experience very compelling, but it cannot be extrapolated to the population.

    What you describe is a very severe case of GBS – Most cases are not nearly as severe, and recovery is usually very good.

    In any case – the risk of GBS from the vaccine is about one in a million – which is the background rate of GBS. The risk of GBS from the flu is much higher, and the risk of dying from the flu is much higher.

    I agree that people should make informed decisions – informed by all the facts, not a few scary anecdotes.

  22. peterlee says:

    I suffered GBS nine years ago. I had received no injections prior to the diagnosis, but I regularly had close contact with others…I “caught something.” I was five thousand miles from my home as nausea and vomiting occupied me for twenty hours. The following day, I noticed difficulty in walking. The paralysis ascended, and it was diagnosed as GBS by physicians at a Kaiser Hospital. The condition is also known as “ascending-descending paralysis”, and indeed it ascended one night into my thighs. I began to give up hope, particularly after meeting a man who’d just spent a year on his back with maximum GBS. But three weeks of GBS…and my paralysis started descending. I was lucky.

    I had some time to read, and discovered that Guillain and Barre were two French physicians who first diagnosed this condition during World War One.

  23. peterlee says:

    Now I live a perplexing life during flu season. Do I lie to the staff about my GBS, so I can receive a flu shot (risking a re-occurrence), or do I worry about getting H1N1, since I’ve skipped the shot? I am not a lawsuit-prone patient, but what seems to be required of me to make this decision is some subterfuge.

  24. snowflake says:

    HI Steve,

    you correctly ask the most obvious question, one for which I have been seeking an answer:

    “That is why it is best to frame options in terms of risk – what is the risk of being vaccinated vs the risk of not being vaccinated.”

    Would you be able to answer this with numbers. THe risk of GBS is 1:1 million, as you state, or 1:100,000 according to the CDC.

    What are the risk (in numbers) of serious complication, including death, from the H2N3 and the H1N1 virus. H1N1 apparently affects more children than the H2N3, so separating the risks in children and adults would be useful.


  25. pastorman says:

    People mock those who play lottery games citing statistical data. For example, your chances of being in two plane crashes are better than your chances of winning the lottery. Yet, eventually someone wins… I am aware that not all lottery games are structured the same way and therefore have different odds… but I think the underlying point is clear.

    We can rationalize statistical data in hopes of allaying our own deep seated fears as much as we want; however, the fact remains that someone will be the ”loser” in this situation. That is, having a one in one million chance of developing a serious illness as a result of receiving a vaccination seems to be an acceptable risk… until you discover that you (or the person you care about most) are (or is) that one.

    neurobsn’s case is very relevant because she was that one… I do not believe that it is rational or in any way reasonable for us to talk about this in such inhuman (statistical) terms. The fact is, there is going to be a high cost to someone whether it is H1N1 or the vaccine used to prevent it. There is no such thing as an acceptable loss when you or someone you love represents that human cost.
    That said, this will be something that each individual will have to approach with careful consideration. From what I am seeing, most of the fear-mongering appears to be occurring on the internet and most of the reassuring on television (with some notable exceptions). I simply wish we could have an open, honest, two sided dialogue about this issue and that the population at large could have access to that information.

  26. peace says:

    You’ve all gone mad!

  27. sama says:


    In canada the adjuvanted H1n1 vaccine being administered is called arepanrix, produced by glaxo smith kline. In their product information leaflet on page 23 it states this:

    Very Rare (may occur with up to 1 in 10,000 doses):
    • •
    Vasculitis (inflammation of the blood vessels which can cause skin rashes, joint pain and kidney problems)
    Neurological disorders such as encephalomyelitis (inflammation of the central nervous system), neuritis (inflammation of nerves) and a type of paralysis known a Guillain-Barré Syndrome

    to view please go to:

    please explain

  28. vaccine patient says:

    I received the H1N1 vaccine on monday nov 2nd, by mid day nov 4th I had numb fingers on one side of my body, then the following day numb fingers on the other side of my body. by thursday night I had numbness in both feet and both sides of my face.

    I am a healthy male in my 30’s. I received the h1n1 shot to protect my children from h1n1 exposure.

    I am currently writing this from a hospital bed in a major hospital in toronto.

    I am hospitalized with what is probably GBS. The only way they can now diagnose this properly is with some invasive tests.

    The risks of getting GBS are real. I think the issue is, how many patients get a life threatening form of GBS vs. a mild form.

    How many patients are educated enough to know the symptoms of GBS? If you are reading this, do you know the symptoms? do you know what to look for?

    I still believe that the rewards of the vaccine outweigh the risk, but the public should know the risk. The public should know that it is not fearmongering.

    I am in the hospital so that i can be treated if the disease progresses. I can look forward to numbness moving up my legs and arms, leg cramps (i started to get those this morning), if it moves to my chest I may need a ventilator.

    If this can happen to me, it can happen to anyone.

    Thankfully i’m being taken care of a team of doctors and specialists who recognize GBS is real and can be a side effect of the H1N1 vaccine.

  29. The problem with all stories such as yours is that they are anecdotal. Millions of people get the flu vaccine, and by chance alone some will come down will illnesses following the injection. We cannot assume cause and effect. We need large statistics to do this.

    Evidence over the last 30 years is inconclusive as to whether or not there is any risk of GBS from the flu vaccine. Worst case scenario, there have been 1 excess case per million vaccines.

    GBS associated with H1N1 will be closely monitored this season, so if the risk is greater we should detect it early.

  30. vaccine patient says:

    the problem with my story is that it is anecdotal?

    I am not stating that it is not safe. I am not stating that people should not get it. I am not stating the risk outweights the benefit.

    The reality is GBS is a real risk. How many people do you think get a mild form of GBS that goes away within a few days or few weeks of getting the shot that never need or seek medical care?

    The problem lies with the information given to the public that there is not a risk. The stats also say that it’s 10-20 per million, so it’s really 1 or 2 per 100 000.

    I’m not here to debate this. i don’t need to. i’m sitting here in a hospital with numb legs, arms, face and the GBS symptoms are increasing. Am I really a 1 in a million pheonomena?

    The problem is that only a small percentage of people have been vaccinated and from the people vaccinated there are many who have sought medical treatment. You have not heard that in the media yet….but you will.

  31. vaccine patient says:

    In a previous post if I read it correctly Steven Novella is a neurologist. Dr. Novella, I appologize if my prior post seemed rude. It was not my intention. May i ask where you are a neurologist? Perhaps the specifics of my case may be of interest to you. I may be interested in going into more detail with you outside of a public forum.

  32. sama says:

    question for steven novella

    Why would glaxo smith kline put in their product information leaflet on arepanrix which also can be viewed on health canada’s website at:

    The media, DR’s, you are all saying that potential for neurological damage is extremely rare. then why does GSK in their section for on side effects for consumers report this:

    Uncommon (may occur with up to 1 in 100 doses):
    Tingling or numbness of the hands or feet

    Rare (may occur with up to 1 in 1000 doses):
    Severe stabbing or throbbing pain along one or more nerves

    Very Rare (may occur with up to 1 in 10,000 doses):

    * Vasculitis (inflammation of the blood vessels which can cause skin rashes, joint pain and kidney problems)
    * Neurological disorders such as encephalomyelitis (inflammation of the central nervous system), neuritis (inflammation of nerves) and a type of paralysis known a Guillain-Barré Syndrome

    Steven – 1 in 10000 doses is a big difference than 1 in a million. 1 in a 100 doses could get numbness and tingling of hands and feet?? 1 in a 1000 could get fits. This all sounds neurological to me. As I asked before please explain why the vaccine could be causing this. why the discrepancy between what the media and Dr.’s are saying and what the company who made the vaccine is saying. It is GSK information and health canada’s admission in the beginning of the document that have given me pause “Health Canada has authorized the sale of Arepanrix™ H1N1 based on limited clinical testing in humans” I am healthy and would rather get the flu than have a new vaccine that has had limited clinical testing.

  33. sama says:

    question for steven novella

    Why would glaxo smith kline put in their product information leaflet on arepanrix which also can be viewed on health canada’s website at:

    The media, DR’s, you are all saying that potential for neurological damage is extremely rare. then why does GSK in their section on side effects for consumers report this:

    Uncommon (may occur with up to 1 in 100 doses):
    Tingling or numbness of the hands or feet

    Rare (may occur with up to 1 in 1000 doses):
    Severe stabbing or throbbing pain along one or more nerves

    Very Rare (may occur with up to 1 in 10,000 doses):

    * Vasculitis (inflammation of the blood vessels which can cause skin rashes, joint pain and kidney problems)
    * Neurological disorders such as encephalomyelitis (inflammation of the central nervous system), neuritis (inflammation of nerves) and a type of paralysis known a Guillain-Barré Syndrome

    Steven – 1 in 10000 doses is a big difference than 1 in a million. 1 in a 100 doses could get numbness and tingling of hands and feet?? 1 in a 1000 could get fits??? This all sounds neurological to me. As I asked before please explain why the vaccine could be causing this. why the discrepancy between what the media and Dr.’s are saying and what the company who made the vaccine is saying. It is GSK information and health canada’s admission in the beginning of the document that have given me pause “Health Canada has authorized the sale of Arepanrix™ H1N1 based on limited clinical testing in humans” I am healthy and would rather get the flu than have a new vaccine that has had limited clinical testing.

    Again please comment

  34. vaccine patient says:

    still in the hospital….my reflexes are less reactive….the numbness is going up my arms and limbs……I am not having some muscle weakness.

  35. vaccine patient says:

    last post should have said

    i am NOW having some muscle weakness

  36. daedalus2u says:

    sama, it is statistics. These particular formulations have not been tested in sufficient numbers of patients to put lower limits on the chances of adverse effects. If it has only been tested in ~10,000 patients; you can’t put a limit different than 1 in 10,000 unless you do many times 10,000 patients.

    Other flu vaccines have been tested in more patients and so other vaccines do have higher limits. There are many things that can cause GBS.

    This paper does talk about some of the epidemiology of GBS. The “normal” incidence is 1-3 cases per 100,000 per year. Some data suggests that there is an increased risk in the 6 weeks following some types of vaccination, but even if that risk were ~8x higher during that period, the total risk per year is only changed slightly ( TR/yr = (8*(6/52)+1*(46/52))*(1-3) = 1.8-5.4 per 100,000). That increased risk would be hard to see unless you had millions of patients.

    The chances of getting GBS from a C jejuni infection are estimated at 1 in 1058 and for a specific serotype (O:I9) 1 in 158. Other infections cause GBS too. Flu might cause GBS. GBS does occur after an infection, including respiratory infections, including flu-like infections and (apparently) following actual flu. This study was based on another type of flu, not H1N1. Will H1N1 be better or worse? We won’t know until next year when it will be too late.

    Package inserts are not “scientific” documents; they are “legal” and “marketing” documents. What is said in them is not determined by “scientific” considerations but by legal and marketing considerations. A Canadian package insert is regulated according to Canadian law.

    This particular formulation of vaccine does have limited in human testing. This particular strain of H1N1 flu also has limited in human testing. So far, it looks like the risks of this strain of H1N1 flu greatly exceed the risks of the vaccine, especially for children and pregnant women.

    I don’t understand what basis you are using to determine your preference for the unknown effects of the flu vs. the unknown effects of the vaccine.

  37. weing says:

    By their definition rare events are those that occur less than 1 in 10000. It is in the same category if it occurs 1 in 10 million. So if an event occurs up to 1 in 10000 it’s considered rare.

  38. sama – in addition to what Daedalus wrote – transient tingling in the hands is not the same as GBS.

    There are many published studies on GBS following vaccines. These report rates of from 0.4 to 1.7 cases of GBS per million following flu vaccines, and 0.75 cases per million for all vaccines.

    The background rate of GBS is about 1 per 100,000 per year – or about 10 per million per year, which is about one case per million every 5-6 weeks.

    So, by chance alone, we would expect many of these cases of background GBS to occur within 6 weeks of a flu or other vaccine.

    There is some evidence of increased risk of GBS in the 6 weeks following a flu vaccine.

    So – (the evidence being imperfect) it is unclear if there is a real increase in risk in GBS from the vaccine, but being maximally conservative there may be an excess of 1 GBS case per million vaccines.


  39. vaccine patient says:

    Dr. Novella, have you got the h1n1 shot?

    If not, please do and document your reaction

  40. pnnash says:

    I had a seasonal flu vaccine October 5th and an H1N1 vaccine two days ago (Sunday). I am now experiencing tingling in my fingers and toes.

    I went to my primary practitioner yesterday who told me to “sit and wait” to see if anything develops. He admits that he has no exposure or experience with GBS.

    In your opinion, is there anything else I should be doing? I feel like a sitting duck that could be doing something more proactive to insure this tingling doesn’t turn into a more severe problem.

  41. provaxmom says:

    vaccine patient:

    Is your question a lame attempt at a “gotcha!”? Seeing as Dr. N works in health care, I would think getting it to protect his patients would be valuable. Otoh, seeing as there is a shortage right now and he is in a low-risk group (can only judge age by photo on here 😉 ) not getting it at this point in time is a legitimate argument. There are still thousands and thousands of asthmatics and preggos in this country who can’t find it, it almost would be irresponsible for Dr. N to use one up right now.

  42. My clinic is currently out of the vaccine. As soon as they get in new supplies I will be lining up to get both H1N1 and seasonal flu vaccines. I will certainly report on my experience – but I caution that anyone’s anecdotal experience is of extremely limited utility.

    My daughters are both signed up to get the H1N1 vaccine at their school – again, as soon as they come in.

  43. pnnash – Many people report transient tingling in the hands or feet after vaccines. Very few of them go on to develop GBS. There is nothing to do but monitor symptoms. If they progress, especially if they evolve into weakness or numbness, then the thing to do is to seek immediate medical attention for further evaluation.

    But keep in mind – GBS should follow an infection (or vaccine) by at least several weeks. It is a secondary immune response. Immediate symptoms following the vaccine are not very worrisome for GBS, and are likely just transient symptoms.

  44. pnnash says:

    So it sounds as if I should just watch for numbness or weakness. I would guess at that point I should seek the attention of a neurologist and not just my primary care doctor.

    I wonder how much thinking about this is making everything worse!?!? My husband tells me to stop worrying, which is hard to do when your body is responding in a way it normally doesn’t.

    I get a seasonal flu shot each year and chose to get the H1N1 shot because I had pneumonia two years in a row. Personally, I don’t think I will again.

  45. johnma says:

    Steven, you make reference above to “neurobsn” case of gbs being very severe. I don’t agree with this. I contracted gbs on Nov 2002 and became completely paralysed within a few days. I spent the next 8 months in ICU on a ventilator and the following 10 months in other wards including the rehab ward. When I left hospital 18 months later I still had virtually no movement in my legs and hands and full or partial paralysis of every other muscle in my body including vocal cords, tongue, face muscles and diaphram.
    I have improved since then but still have no muscle movement below the knees and still have full or partial paralysis of everything else. I have managed to ditch the wheelchair for a seat walker and am at a stage where life is great compared to where I was. During my time in hospital (Canberra, Australia) and since then I encountered several other GBS patients who were very severely affected including another young medical student who has a nearly identical story as me except his legs didn’t improve too well and he uses a wheelchair permanently. I am only mentioning this so your other readers are aware of what very severe GBS is!

  46. sama says:


    thank for your earlier reply.I stand firm in my reservations at health canada’s declaration that this vaccine has had limited clinical testing done on humans. I feel much more comfortable waiting it out this year to see how others who choose to get the vaccine respond.

    What I am really interested in understanding is, why someone would experience numbness and tingling at all. what is happening physiologically post vaccination that would cause such a reaction? why and how is the nervous systembeing affected by a vaccine in such a manner as to cause N&T or fits, let alone GBS?


  47. johnma – see the links I provide above. In a review of cases of GBS following vaccination, the death rate was 3.2% and the rate of disability was 16.7%. Those are the stats – and they are fairly consistent among studies.

    I am sorry you had a severe case – but you cannot make conclusions about the natural history of GBS from your anecdotal experience and random encounters with other patients.

    80% of GBS patients have complete or near complete recovery.

  48. sama – it is probably from a transient immune activation, which is known to occur with vaccination. Many people (myself included) will get similar symptoms with a viral illness such as a cold.

    Also, keep in mind – this vaccine is the same flu vaccine that has been used for decades. It is just targeted at the current H1N1. We have decades of experience and millions of doses of flu vaccine given with this same technology.

  49. pnnash says:

    Steven- Going to see neurologist today. Tingling still transient, but also now experiencing twinges in my legs, feet and back. No muscle weakness. Have you experienced the body being able to “kick” something like this on its own? Still concerned…

  50. Such episodes are usually monophasic – they last for 2-3 weeks then resolve on their own. However, if they are significant, treatment can minimize damage during the episode.

    Seeing a neurologist is a good idea. I can only give general advice remotely.

  51. pnnash says:


    Thanks for your input and quick response. Saw a neurologist today. Exam was normal. Passed all reflex tests etc. His thought was just to wait it out as well. He said the same thing- normally within 2-3 weeks things subside. Didn’t seem to think it was showing itself as GBS due to normal motor functioning, but of course said to follow-up if I loose muscle control, have double vision etc. Also gave me Lyrica to help subside uncomfortable nerve feeling.

    I always seem to find myself in the “undiagnosed” category.

  52. pnnash says:

    Great… new symptoms include twinges around my sides and left calf with right calf and thigh feeling “odd”. Feet still sore. Back still sore. This is odd.

  53. pnnash says:


    I thought you might find this link interesting:–Vaccine-/Tingling-after-Swine-Flu-Vaccine/show/1092119

    Do you think all of these people are just coincidentally experiencing symptoms like mine?

    I am obviously not the only one who is experiencing this, which is oddly comforting. But it doesn’t of course fix the problem.

  54. daedalus2u says:

    I have a question for Dr Novella, is the mechanism for transient tingling following a vaccination known? I have been reading up on GBS, and it is due to the formation of antibodies that attack nerves and so affect their conduction.

    Antibodies take a certain period of time to form, the antigen has to be taken up and various immune cell things have to happen and then the antibody producing cells have to clonally expand until they start producing enough antibody to have the effects, so prompt neurological effects (few days) are almost certainly not GBS (unless coincidental with an earlier infection and unrelated to the vaccination).

    Antibodies are not the only mechanism by which inflammation can be caused. There are plenty of pro-inflammatory cytokines that are promptly released in response to immune system activation. I suspect that those other pro-inflammatory cytokines would be the cause of tingling from vaccines.

    I am always interested in nitric oxide effects, and during conditions such as sepsis, the NO level becomes very high, high enough to cause systemic hypotension. NO also inhibits mitochondria by inhibiting the binding of O2 to cytochrome c oxidase. During sepsis, in muscle cells (measured by biopsy and I think the same thing happens in essentially all non-nerve cells), mitochondria are “off” due to the high NO levels (which also causes high ATP (via sGC) which also turns off mitochondria). In nerve cells, mitochondria can’t be turned “off” because nerve cells don’t do glycolysis to make ATP. In nerves, the NO level at the location of the mitochondria has to be kept below a certain level (so that the mitochondria remain on). One way to do that is to produce neuroinflammation on the outside of the nerves, so that the NO gets consumed before it can diffuse inside. The myelin coating of nerves is transparent to NO, but the alternating layers of lipid and aqueous phases would significantly spread that NO out along the length of the nerve (NO is 10x more soluble in lipid than aqueous). This would allow a few NO sinks along the axon to control the NO concentration along the length of the axon.

    There are some other neurological conditions caused by antibodies, for example Sydenham’s chorea which is caused by anti-strep antibodies (which is why it is always important to treat strep infections with antibiotics before a high titer of antibodies can form). A significant cause of death before antibiotics was strep infection, in particular puerperal fever. Nitric oxide prevents Strep (and other bacteria) from forming a biofilm, which I think is the reason that sepsis evolved to be a very high NO state. Having bacteria floating around in your blood stream is bad, if they attach and form a biofilm your chances of survival have gone down at least an order of magnitude. Avoiding a 95% chance of death (bacteria forming a biofilm) with a process that has a 50% chance of death (septic shock) is a great evolutionary trade-off.

    A major cause of headache is migraine which is known to be due to ischemic preconditioning brought on by superoxide, by neuroinflammation. The headache of fever might similarly be due to neuroinflammation to protect the CNS from too high a NO level. Blocking that neuroinflammation might block the pain, but might also exacerbate potentially damaging high NO effects (because blocking the inflammation allows for higher NO levels). In the context of vaccination, “stress” does act as an adjuvant and so causes the vaccine to produce a more severe immune response and results in a higher antibody titer.

    We know there is nothing unique about vaccines that would specifically affect nerves. In particular if there were some sort of “toxin” in a vaccine, at the injection site the level is at least hundreds of times higher than what would occur elsewhere, if there are no local effects on nerves and mitochondria local to the injection site, it is very doubtful that there could be effects remote from the site other than via immune system effects.

    Vibration does cause local production of NO. I have an idea that the nerve problems and Raynaud’s following chronic vibration (as in occupational exposure to vibration such as jackhammer use) may be due to a compensatory reduction in NO levels inside nerves to compensate for the chronic local increased NO due to the vibration. The NO/superoxide balance has to be pretty exact to balance each other, and if they get out of whack tingling might be the result.

  55. pnnash says:

    Had a thought this morning…

    I received both my seasonal flu shot and H1N1 shot using the new PharmaJet technology, which is a needless system of injecting the vaccine. The jet injectors create a fine stream of pressurized liquid that penetrates the skin to deliver the vaccine.

    I wonder if there has been any common thread of increased tingling/nerve pain from those that had a PharmaJet delivery?

  56. daedalus2u says:

    pnnash, I really doubt that. That technology is similar to what was used a lot do administer smallpox vaccine by the millions in rural Africa because it didn’t require needles.

    At most it could have a local effect at the site where there was tissue damage. Any effects remote from that site (and I assume the nerve tingling was remote), have to be mediated by a mechanism that is either local to the site of tingling, or a mechanism that affects the neural pathway back to the brain.

    Maybe the dosing is not as precise as with injection via needles, but it is hard to imagine it being off by even a factor of two. Maybe there is some difference in how the dose distributes itself in the tissues, as a single large bolus (via needle injection) or with lots of little microtraumas (the jet injection).

    When cells are damaged and spill their contents into the extravascular space, some of those cellular contents do act as adjuvants. Maybe there is a difference between the immunological effects of a jet administered vaccine compared to a needle administered vaccine. When the jet device was FDA approved, what drugs were administered with it to show equivalence to needle injection? I presume things like insulin which have to be injected multiple times per day, rather than vaccines which (mostly) are injected only once in a person’s lifetime.

  57. daedalus2u says:

    I looked a little into jet injections. One technique Pharmajet does say that it takes reduced quantities of vaccine to produce the same antibody titer, sometimes as little as 1/5 the quantity of vaccine produces equivalent antibody titers.

    To me, this suggests that the skin trauma from the jet injection is acting as an adjuvant.

  58. pnnash says:


    So I likely had a reduced quantity of the vaccine with the PharmaJet, but may have had a larger antibody reaction due to method it was administered? Is that correct?

  59. daedalus2u says:

    pnnash, you might have had the same amount of vaccine (half a mL), but you might have had 5x the response. You might have had the equivalent immune response to receiving 5 vaccinations simultaneously. This is all highly speculative based on casual marketing remarks on the Pharmajet website.

    I suspect that some of this is because doing this kind of research is pretty difficult. Mice and rats have different skin thickness than do humans, so doing vaccine comparisons by delivery mechanism (needle vs Pharmajet) is tricky and problematic because the length scale is important and is different in mice and rats vs in humans.

    I was surprised when I looked at the applications section that they were focused on vaccines and not on daily injectable meds like insulin. In thinking about it more, I think it is due to marketing by the suppliers of the daily injectable meds. They don’t want to lose control of the delivery mechanism by allowing non-needle injection.

    This different delivery mechanism probably requires new clinical trials for use in insulin. A 5x difference in biological effectiveness in insulin would be a gigantic deal and could even kill people. Vaccines have a much wider acceptable dose range.

    The antibody reaction is still going to take the same time scale, so what Dr Novella said about it not being GBS is probably still true. No matter how many vaccines you get it still takes a while to develop the antibodies. You might develop more antibodies but the time scale would still be weeks. But the non-antibody immune response might be higher and that is probably what caused the prompt effects. If so, then worrying about it will likely only make it worse. (stress all by itself acts as an adjuvant).

  60. pnnash says:


    Thanks so much for your insight.

    Still brings me back to a thought I had- Do you think it could be a coincidence that the symptoms began the evening I received the H1N1 shot (11/8), but that it was in fact the seasonal vaccine (10/5) that triggered the issue?

    I am still experiencing the tingling (radiates sporadically though body), light spasm/muscle cramping (calf, axilla, feet) and just feel “off”. I am going back to the neurologist tomorrow.

    Is there anything specific you (or anyone participating in the is blog) would recommend they look for/test for at this point?

  61. daedalus2u says:

    I think what you need is rest and to let your body re-adjust its physiology. I suspect but IANAD that you are very far from a condition that is considered pathological enough to treat, and that until your body has gone through the process of responding immunologically to the vaccine, that there is nothing that any reputable doctor would do. Stress and worry is probably the worst thing you can do for it. What you need is rest and relaxation.

    Again, IANAD, but from what Dr Novella has said, transient nervous-system-like reactions are not unheard of. Serious and long term reactons are very rare and worrying about very rare events usually does more harm than good.

    But listen to what your neurologist tells you, not what random anonomous people say over the internet 😉

  62. gers says:

    I am a layman in this field so forgive me if I forget some elements in my question: This article has shown that risks of GBS are low enough to discard. But the main question was, as far as I understand, that the virus could mutate and had a risk of becoming dangerous, hence the decisions by governments to invest in massive vaccine production as part of a precautionary principle.
    Now that we are in november, and that the virus has proved not as dangerous as we originally feared, is it fair to say that there is less relevance to get a shot of the N1H1 vaccine?

  63. cwmoore says:

    I had GBS 17 years ago after having a virus. My case was not caused by the flu vaccine, but my neurologist still told me to never again get a flu vaccine.
    That was a long time ago, medically speaking. Is this information still valid?

    My question: should I get the flu shot now?

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