Why the epidemiology of swine flu matters

If you are hesitating to be vaccinated for swine flu this year, perhaps this post will help you make up your mind. If it does, I hope it pushes you to get vaccinated, but whatever persuasion we attempt here will only be from a recital of what we know of the epidemiology of this pandemic. Because it is the different epidemiology that is the main feature, not the clinical characteristics or the virulence of the virus. So far this looks pretty much like a standard influenza A virus -- except for the epidemiology. Since I'm an epidemiologist, you might expect me to think this is important, and I do. Epidemiology is the public health science that studies the patterns of illness in populations. One kind of pattern we study is who is getting sick. And it is a change in this pattern that is one of the big differences between a pandemic strain and a seasonal strain.

Pandemic strains have a greater tendency to infect and make sicker much younger victims. In seasonal influenza it is the over 65 age group that contributes most of the serious illness and deaths, but with pandemic strains (not just the current one), lack of immunity in the population makes those under age 65 a bigger target and they sicken and die proportionately more than in a non-pandemic season. And that's exactly what we are seeing this year. The story that made the headlines on Friday was that 19 more pediatric deaths were added to the pediatric death toll in week 39, although not all of these children died in that week. The dates of death for the 19 stretched between July 19 and October 3 because of the way the tally is done. Starting in the 2003 - 2004 flu season deaths from influenza in people below the age of 18 became a nationally notifiable disease, reported to CDC through state epidemiologists. Each state has its own way of ascertaining the number. Some states are more complete and more timely than others, so notifications that come in a particular week can, and do, represent deaths that occurred over varying time periods, as in the instance of the 19 added this week. Still, it is clear that the young population is being hit particularly hard in comparison to the last three years for which we have data. 76 have died from swine flu since it made its first appearance in April, and 29 of those deaths have come since August 30, i.e., 29 in 5 weeks and those 5 weeks are extremely early in the flu season. In fact they occurred before the official administrative flu season even started (week 40).

The pattern of pediatric deaths and its difference from previous years is dramatically shown in this graph from CDC's weekly flu report:


The green bars are pediatric deaths from seasonal flu. You can see that in green bar terms, this flu season, which was not as bad as the previous year, was pretty typical. But this year, unlike previous years, there was a second flu season that started just as the usual one was finishing (the middle hump). We remarked on this back in July. Then there was a lull (we don't know why) and now we are into flu season and we see a third set of bars.

If you aren't in the pediatric population, here are some more patterns that may help convince you that getting vaccinated is a good idea. This comes from the Emerging Infections Program (EIP), another part of the multicomponent CDC flu surveillance system. These are lab confirmed influenza related hospitalizations in 60 counties in 12 metro areas of 10 states (San Francisco CA, Denver CO, New Haven CT, Atlanta GA, Baltimore MD, Minneapolis/St. Paul MN, Albuquerque NM, Las Cruces, NM, Albany NY, Rochester NY, Portland OR, and Nashville TN). It's a passive surveillance system where the data are obtained by record review of lab and hospital admissions databases and infection control logs. Each panel is an age group, with the top being babies and toddlers and the bottom one people over age 65 (you can see the original here if this is too small).


These are cumulative incidence rates. Think of them, at each week (the horizontal axis), as the chance that you will have gotten the flu by that time this year, i.e., if you look at week 37 the height of the curve reflects the probability that by week 37 you would have gotten flu at sometime before that (not necessarily that week). Obviously the curve can only go up, since it is cumulating (adding onto the pile of previously lab diagnosed hospitalized cases that have occurred up to that week). If you wonder how high it "should" go, based on the average of the last three flu seasons (October to April of each year) that level is the dashed horizontal line in each panel (NB: the scales are different for the top and bottom panels, because those are the age groups, the very young and the old, that usually have the highest risks so the curves wouldn't fit if the vertical scales of the other age groups was used). What this means for interpreting the curves is that if this year behaved like the average of the three previous years, the curve would slowly move upward until it reached the dashed line by the end of the flu season in April or May. Obviously this year is very different.

You once again see the altered age pattern, this time very dramatic when comparing the youngest age group with the oldest. For those of us in the over 65 age group, the seasonal has barely begun. We are just inching our way up from typical summer levels. There's a long way to go before we get to where we would usually be by the end of flu season. My age group looks pretty normal for this time of year. But if you look at the other panels you see that several have already exceeded, in the first week of the official flu season, the level of season risk we would have expected by the end of the season. Babies and toddlers are two thirds of the way there already (remember the scale is different for them so the same height is a higher risk than compared to the 2 to 4 year olds). The 2 to 4 year olds are already there and everyone between 5 and 49 years old has already exceeded their year end risk at a time when the season is usually just starting. The 50-44 year old group is already at seasonal average and then there's the over 65 age group, the exception that proves the rule: this is a pandemic strain.

Where and when it will peak we don't know but there's a long, long way until whatever causes flu to be seasonal is ended (usually sometime in April or May). Swine flu could burn itself out before then (but not before taking more children and adults with it); or it could keep going for the whole flu season; or it could co-circulate with the seasonal flu H1N1 and H3N2 strains. The assumption that swine flu will completely crowd out seasonal flu strains is premature and we could have a normal seasonal flu pattern in the over 65 age group appearing later. Or not. We still don't understand flu well enough to predict with any confidence what is going to happen.

The seasonal and swine flu vaccines are not intrinsically different except for the flu strains they contain. We change flu strains every couple of years routinely and these vaccines are made in the same way as we have been making them for many years. The only difference is a strain change, which is routine. This means that we have had extensive experience with the swine flu vaccine already, extending over years and hundreds of millions of delivered doses. It is not untested. Far from it.

The most rational thing to do at this moment, given what we know and don't know, is to get vaccinated with both seasonal flu and swine flu vaccines. That's what I'm going to do. I already got my seasonal flu shot and I'll wait in line for my turn for the swine flu vaccine and get it as soon as I can. You not only protect yourself but you help prevent spread of flu to others.

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"The seasonal and swine flu vaccines are not intrinsically different except for the flu strains they contain. We change flu strains every couple of years routinely and these vaccines are made in the same way as we have been making them for many years. The only difference is a strain change, which is routine."

I wish you would make it clear that this does not apply in Canada, or in Europe, where the adjuvant AS03 will be added to the vaccine for the first time.

The Same age-pattern is observable in Germany (Figure 1 here: http://www.scienceblogs.de/weitergen/2009/10/impfempfehlung-gegen-schwe…). Note that young age-groups are subdivided, therefore the peak of new H1N1 influenza infections is more drastic than depicted in the graph.

The German commission for vaccination issued a document last Friday recommending vaccinations for medical personal, chronically sick and pregnant women (link in the blogpost above). Generally the vaccination of a large portion of the population is seen more critical in Germany, largely because the H1N1 vaccines contain higher concentrations of adjuvants.

Stoker: You are correct, although I am not very concerned about the adjuvants. But that's a personal opinion.

Tobias: Danke. Very interesting. The lack of risk in the older age group is even more dramatic and in comparison to seasonal flu extraordinary.

I am asking the next question to prepare, not panic.
With the rise in hospital admittance - will our hospitals fill up? If so when?
With that said - what can be done now (actions, plans or coversations) to deal with this?
H1N1 has shown up in Alabama, Florida and Virginia - as well as more than 50% of US college campus.
If vaccinations start next week on Oct 15th - should that have any bearing on "Trick or Treat" where kids go from house to house collecting things??

As always - thanks for the blog.

Those who forward joke emails should forward this information as well.

I understand the numbers depicted in the graphs but I am still asking myself to what degree the graphs are influenced by deaths amongst high risk patients with underlying conditions. Your comments would be more persuasive if we could see results just from average health individuals. I am inclined to believe the present results are skewed by high risk cases. No doubt h1n1 is a threat to such persons but we must take care about gereralizing for the rest of the healthy population.

I'me with revere here on the matter of the AS03 adjuvant. This adjuvant is nothing more than water mixed with squalene + tocopherol (vitamin E) + polysorbate 80. Squalene is found in all kinds of animal and vegetal foods, especially fish liver and olive oil. Polysorbate is an emulsifier already used in a lot of pharmaceutical and food preparation. Vitamin E... Well, I think the name says all!

Moreover, AS03 has recently been used in a malaria vaccine study including 3700 children and infants.

GSK reports that the AS03 adjuvant was also used in clinical trials for flu vaccines involving more than 39,000 people. GSKâs pre-pandemic and pandemic avian flu vaccines, both of which contain AS03, have received regulatory approvals in both the European Union and some Asian countries.

FYI the lower graph does not represent deaths, only hospitalizations per 10,000 population.

Regardless of healthy or "at-risk" status the numbers we see on the graph should tell us that we will have a much larger number of hospitalizations by the end of the season (if the trend continues). If you're in either of these populations and you receive the vaccine you cut down on the number of primary and secondary infections that may require hospitalization, and do a service to those most at risk from you being the reason they are put in hospital.

In Australia and NZ 20% of ICU hospital beds were taken with flu patients. I'm sure that backlogged elective procedures and took a toll on resources

Irene:Merci bien for the citations/links. I dealt with the squalene issue in Gulf War research. There is always some risk (in my view negligible, but others are more noncommital) but the world is at much greater risk from a lack of viral antigen. Adjuvants decrease that risk to the world. In the US, however, the anti-vaccination movement would use it to argue against all kinds of vaccinations, so it isn't a clear cut issue, even assuming the adjuvant is acceptably safe (and I do believe it is). So in my view the anti-vax movement is not only putting US children at risk but the people of the world.

As with Graeme,I appreciate the graphwork but for the profundity to really get my attention I would like to see the same data for "normal healthy" vs. compromised individuals.

As a layperson, if this is inconsequential, it would be helpful if you could explain to me why it is so.

I'm trying to get my brain around all that I read here, to make better decisions for myself and loved ones....
annnnddd, argue more effectively with the growing number of anti vaxer tinhatters around me that seem to suck up every negative, poorly substantiated, hack fact that then somehow becomes the new Gospel for those REALLY "in the know".

glock, Graeme: These graphs are from a population-based surveillance system so it is meant to indicate what was going on in the community. What it is showing is that hospitalized cases and pediatric deaths are being strongly affected by the virus. The hospitalized cases also provide some indication how likely you are to wind up hospitalized, but it doesn't take account of risk factors. We know what some of the risk factors are (chronic lung disease and asthma, pregnancy, etc.) but about a third of ICU cases in the southern hemisphere had no discernible risk factors. So you are worse off if you have a risk factor (that's what it means to be a risk factor) but if you don't have one, you are still at considerably greater risk than during the usual flu season if you are in the right age group (i.e., baby, toddler, young adult, etc.). Of course I'd love to be able to tell you your individual risk, but we can't do that yet (I'm not een sure what it would mean), but the general population risk is increased. And flu is a lousy disease, which, like an auto accident, has the unpredictable potential to cripple or kill you.

Another question maybe to consider regarding the age-distribtion: in Germany about half of the registered infected people return from holidays, only the other half are infections within the country. Do young people travel more or get easier exposed to the virus on holidays? To what extend does this skew the graphs?

Reveres --
re: "Then there was a lull (we don't know why) and now we are into flu season and we see a third set of bars."

As a complete layperson, I suspect that the tapering off in early summer corresponded with school being let out and the uptick corresponded with schools coming back into session. The last day of school tends to vary geographically -- in Florida, the schools are out around the first week in June, then they return EARLY -- August 24th. I was in Jacksonville during the first week back to school, and the news was all about the Swine Flu outbreaks in local schools every single night. Based on the TV news, it seemed like things picked up when public schools started back and when college students returned to schools. Obviously this is a hypothesis, but maybe someone with some expertise can prove it?

Regardless, everyone still needs to get vaccinated. I cannot imagine anything worse than knowing that the choice not to vaccinate resulted in the death or serious illness of a loved one. I think that one of the main reasons that parents are resisting the vaccinations is that the mainstream media downplayed this as a "mild" flu. From a public health standpoint, I guess it made sense to downplay the situation until there was a vaccine and in order to prevent a panic leading to the health care resources being overwhelmed. However, a big opening was provided for the anti-vaxxers to spread their propaganda. However, while figuring out the appropriate public healthcare messaging may be difficult, the ultimate solution is quite simple -- GET VACCINATED!

@3: revere, if your child were in line for an adjuvanted vaccine and you had watched her fighting for her life from an auto-immune disease, would you be concerned?

@6: "This adjuvant is nothing more than water mixed with squalene + tocopherol (vitamin E) + polysorbate 80."

Right, so if it's so benign why is it being added again?

Some NHS managers believe that only around 10-15% of their staff are willing to have this shot (http://www.guardian.co.uk/world/2009/oct/11/swine-flu-pandemic-vaccine-…) so I would suggest that it's addition is going to have a fairly large impact on the success of the vaccination programme in the UK.

Leah: the roots of seasonality for flu are still a mystery. Probability of contact clearly must be a factor but it doesn't appear to be the only factor. The school explanation has been around for decades but hasn't been confirmed as "the" cause. That's all we know at this point.

Stoker: Of course I'd be concerned if children were coming down with vaccine associated autoimmune disease. But we don't have evidence of that despite widespread use. The European products are mainly used in the elderly age groups so perhaps that's the explanation in your terms for why we don't see it. But there is precious little evidence implicating squalene in any disease. I don't rule it out. But the threat of flu is depressingly well documented.

Thank you Revere,

Can you please specify that your recommendation are directed to the people who have access to unadjuvated vaccines (like in the U.S.A. please.

Thank You


Why German Doctors boycott GSK vaccines with adjuvants AS03

Why French doctors of France, Québec, Africa, etc.. boycott it too

Why Silence Reigns in UK

Snowy: I would recommend anyone get the vaccine, whether adjuvanted or not. That's because I feel much more confident about the risks from flu than I am the risks from any adjuvant. So while some of my comments applied only to the US, my recommendations didn't.

Revere you are probbly refering to Novartis adjuvant MF-59

AS03 (Glaxo-Smith-Kline)
⢠squalene 10.68 mg, DL- -tocopherol 11.86 mg, polysorbate 80 4.85 mg

â MF59 (Novartis)
⢠squalene 9.75 mg, polysorbate 80 1.175 mg, sorbitan trioleate 1.175mg

As you can see there is a dangerous difference.


I got my H1N1 shot on Saturday. However, here in Australia, they're from a multi-dose vial, which is freaking out my friend, and preventing her from getting it even though she's heading back to the northern hemisphere for southern summer/northern winter.

By ayeung213 (not verified) on 11 Oct 2009 #permalink

Snowy: I don't see the dangerous difference. What do you think it is and why do you contend that it is especially dangerous?

Snowy: I'm aware of Susan's position on this. She and I have agreed to disagree. But that doesn't answer my question. What is the dangerous difference as you understand it? Because if you don't like AS03 you also won't like MF59 I would think, yet you think there is a difference. What is it?

Graeme: I think what you're not appreciating is that "high risk" doesn't mean "sick." There are probably people in your life who are asthmatic/diabetic/etc and you don't even realize it. I can't speak to other diseases, but the asthmatics I know live completely normal, "healthy" lives. So the statement that most serious cases are in those with "underlying conditions" isn't much comfort.

I'm of the position that the U.S. should have just used the adjuvant. Not only are we delaying vaccination for our citizens, we're leaving less for other countries.

As always, Revere, thank you for putting technical information into words that the rest of us can understand.

Of the dozen+ people I know who've come down with the "flu" (NO one seems to want to admit that it's likely swine flu), at least half didn't develop a fever, even when they were very sick. A friend's son was in the ER last night with cough, congestion, headache, and severe vomiting ... no fever. I know that phenomenon was talked about in the spring, but the CDC seems to be ignoring it. Any idea why?

The Australian experience to 21 August shows majority of children hospitalized with severe complications had NO underlying health problems. "Since reporting began, the Australian Paediatric Surveillance Unit (APSU) has reported a total of 98 notifications of children hospitalised with severe complications of influenza. 61% had no underlying medical conditions." In addition, over all age groups,of those admitted to ICU, 42% had no underlying health problem. See the Australian influenza report at http://www.health.gov.au/internet/main/publishing.nsf/Content/cda-surve…

The epidemiology is cause for concern. Don't forget the clinical picture too - often RAPID deterioration. Anecdotally I've heard of young healthy people sitting and talking, feverish, to requiring intubation a few hours later. Others checking all the boxes for "mild illness" and not being treated with Tamiflu, to dying a few days later.

By downunder (not verified) on 11 Oct 2009 #permalink

First Revere,

Novartis has done quite a few more studies and quite a few more control Trials on quite a lot more people.
They have been historically more incline to be more transparent (not perfect) but more transparent on their more rigourous datas, while Glaxo, did theirbest to hide as much datas, specifically on kids only a total of 300 children and with very bad clinical results and they are very reluctant to share and even in some cases to do their best to hide it.

From such a beginning it already give a bitter taste.

but SusanC shared scientific datas and worked very hard to get it.

Here are summaries of all of her hard work

Adjuvants and Pathogenesis of Autoimmune Disease I - Overview

Adjuvants and Pathogenesis of Autoimmune Disease II - Inflammation and Immune Regulation

Out of US
"To Be or Not to Be" Vaccinated? - the Time to Decide is NOW

I'm Angry (or, The Shortest Version on What's Wrong with some Swine Flu Vaccines)

Hat Tip to both of You and from Authentic Scientifics who rejects Omissions.

Snow Owl

Snowy; I know Susan's position and cites well. I reviewed the literature over Gulf War syndrome and reached my own conclusions based on a large body of scientific literature. I think the one thing Susan and I would agree on, is that the issue is anything but "clear cut." It is a difficult scientific issue with risks that have to be weighed and somehow balanced, which is difficult when we are comparing risks to one set of people with different risks to another set of people. I've articulated why I have struck the balance I have. I don't have any more to say on it except that I reject the idea the evidence conclusively shows there is an unacceptable risk.

Off topic, but I don't know where to ask this. I'm looking for evidence for the practice of recommending kids stay home from school if they have a fever and returning if fever free for 24 hours. I'm wondering if this is just sort of tradition, or if there is a really good reason for it. Obviously, if they have a fever they probably don't feel good, but are they really more contagious than afebrile kids who are coughing and sneezing? Presumably they're both shedding virus for days or weeks after the first symptoms, so I'm not really sure what fever has to do with the recommendations. Thanks.

The CDC chart brings up a question: was the low total from '05-06 an anomaly, or do the higher totals from the later years represent a new norm?

By Pierce R. Butler (not verified) on 11 Oct 2009 #permalink

Appreciation, Revere, for this discussion of the epidemiology. One question would be to what extent the use of cumulative figures slows down the spotting of any change in trends--which, should they occur, may need to be recognized quickly.
And thank you, Curious, for bringing up the issue of "underlying health conditions." How does one regard, for instance, ex-smokers with slightly diminished lung capacity for many years? Or someone with near-minimal emphysema and a previous lung nodule (benign) biopsied with minimal tissue removal? Of course, if either patient develops flu and complications, s/he will be seen as having "underlying conditions," but--beforehand?

Revere: "the roots of seasonality for flu are still a mystery. Probability of contact clearly must be a factor but it doesn't appear to be the only factor."

I'd like to know if Revere is familiar with this paper:

On the epidemiology of influenza

The authors' hypothesis (admittedly unproven) is that influenza is a symptom of vitamin D deficiency, and that low winter levels of vitamin D is the flu's seasonality factor.

A point of clarity on adjuvants and the EU authorisations. The EU has approved both the GSK Pandemrix vaccine and the Novartis pandemic vaccine under Emergency Use Authorisation provisions. This means that they accept that full safety and efficacy testing has not been completed nor full data submitted for the regulators to assess, but to counter this lack of data (as the vaccines are being used in an emergency) there will be a heightened level of ADR surveillance and reporting in real time, along with formal clinical trials running in parallel.

Thus an emergency use authorisation by the EU should not be confused with a judgement that the EU regulators are fully satisfied that the vaccines are both safe and effective for all population groups, on the basis of the clinical data submitted to them as part of the authorisation dossier. This is a big difference to a standard licence authorisation.

This information is clearly displayed on the EMEA website on the pages that announce authorisation for both these vaccines for those that wish to look.

As such, until such time as the ADR and/or trial data is in for individuals who are pregnant, may have autoimmune disease, young children etc, no-one can state whether vaccines with adjuvants are sufficiently safe or not in these population groups. Thus risk assessment for these groups has been (by necessity) theoretical at this stage, as there is little or no clinical experience or trial data available for these groups, although there is a more widespread history of safe use in older adults.

By Vibrant62 (not verified) on 12 Oct 2009 #permalink

Jeff: Yes, I know the vit D hypothesis. There are several hypotheses about what might be the forcing function for seasonality and, in my view, they are all plausible and credible. Are they acting together? Is one more important than another? Is it something else? Those are the things we don't know. We also have very little info on seasonality in the tropics, something which would be very useful to know.

Vibrant62: MF59 has been used since 1997 and there isn't much difference between it and AS03, IMO. But adjuvanted vaccine may be inappropriate for certain subgroups (someone very close to me has an autoimmune disorder and doesn't get vaccinated at all), just as live virus vaccine is not indicated for certain subgroups (one of which I am in, over 50). The only vaccine adjuvant in use in the US is alum, and that isn't used for influenza, although it was the adjuvant in the military's anthrax vaccine (making that vaccine mandatory for troops was stupid and probably illegal but as far as we can tell not the cause of Gulf War Illness). If the concern is rare adverse outcomes, there is no possible way to detect it with a pre-deployment clinical trial. As I have said here many times, much of what we have to do in public health involves trade-offs. My view on adjuvants is that I have less confidence that there is much risk from adjuvants than I have confidence that there is a lot of risk from influenza infection and that the evidence shows that the vaccine provides a lot of protection against influenza. It's not 100%. A good match might be 70%. But reducing infection by 70% is a lot better than reducing it by 0%.

Dear Revere, thanks for the response and I see your point. I am actually pro-vaccination in general, but do have reservations on the issue of squalene based adjuvant, based on the available clinical data in these vulnerable popualtion groups.

My point was that when the fact of the EU approval is cited, as it often is in this debate, it does not mean that the EU regulators were satisfied by the safety and efficacy data for all population groups. Clinical experience of use for the MF59 is also largely restricted to older adults with increased ADR signals in younger adults, and there is very little data about its use in pregnancy or very young children, or individuals with auto-immune disease.

In every other area of pharmaceutical intervention the precautionary principle is applied, but not here it would seem. Normally every drug specifically excludes such vulnerable groups until research has satisfied the regulators that it is safe to use in these particular population groups. Clinical experience and use of simple vaccine alone in these population groups is limited, but I agree is unlikely to cause harm and is more likely to provide significant benefits.

I fail to understand why (outside of the US) there has not simply been exclusion groups cited for these adjuvant vaccines within any Regulatory authorisation pending safety data. These individuals could easily receive vaccine without adjuvant at a standard antigen dosage of 15mg. No additional order would be required for the GSK vaccine as the antigen and adjuvant are manufactured and delivered separately. By doing so much of the debate would have been nullified before it ever started - people are used to almost every available drug on the market having such exclusions, on the grounds of 'playing safe', so why not here? The adjuvant vaccine would still be available for the majority, and those who are against vaccines would not have been given such ammunition to muddy the waters around vaccination generally.

By Vibrant62 (not verified) on 12 Oct 2009 #permalink

This is anecdotal, but this weekend I attended the funeral for a friend who died as a result of H1N1. She was an atheletic 28 year old with no risk factors that I am aware of. She got the flu and within a week was in ICU on a respirator for pneumonia. Massive antibiotics and antivirals were unable to defeat it and she simply didn't have enough oxygen in her blood to maintain her brain.

By William Shipley (not verified) on 12 Oct 2009 #permalink

Kevan: There is very little flu data on the tropics. Hong Kong (sub tropical) has some and I wrote a post here about a peak in the rainy season in Nicaragua. It would be nice to get more.

William: Sorry to hear this sad story. This is a typical case of Acute Respiratory Distress Syndrome (ARDS), which has a very high mortality even with the best critical care resources. It doesn't happen often with flu (in proportion to the number of people infected) but when it happens it is devastating and while underlying risk factors increase the chances, typically a third of the cases have no underlying factors, like your friend. It's tough and tragic when this happens to a young person like this and it is another example of why the epidemiology matters. It's flu.

Slightly off-topic, but I wanted to ask this since you are being so good at giving feedback. Dr. Sanjay Gupta on Larry King Live said that babies born from mothers who were immunized with H1N1 vaccine will inherit the immunity. Is that even remotely true?

ticktock: There will be some passive immunity transfered transplacentally. How much protection that provides is unclear (if any), but it wanes in months (if it is effective at all). So "inherited" isn't the right word. The sense, though, I suppose makes it possibly remotely true. Bu the time they are 6 months that's gone and they should get vaccinated.

How often exactly does ARDS occur in healthy people with seasonal flu, or swine flu?

Thank you for putting everything in terms I can understand. I am a college student who is crazy concerned about both myself and my fiance coming down this this since we both have underlying conditions...but due to my class load, haven't had time to sit down and do detailed research on any of this.


I'd like to get the vaccine but since I'm not in practice I'm not in a priority group and can't find any available for the general public yet.

Also, I cannot find SEASONAL flu mist anywhere.

By Lisa the GP (not verified) on 12 Oct 2009 #permalink

Lisa GP,
Come to the south...we have lots of it here.

Ilama and Lisa GP, thanks for putting this in human terms. As an "old person" put last in line for the vaccine yet aware of some contradictory data regarding "over-64"'s presumed relative safety on this--and as a mother--and as a public health editor regularly asked by people for information--I share your concern. I wish, with Revere, that this country would cease eschewing use of adjuvants that could increase our vaccine supply so we could spread it more equitably spread here and abroad.

There is some interesting data suggesting that keeping your vitamin D level optimal will prevent colds, flu and in particular H1N1 (swine Flu). The Canadians are taking the data very seriously and starting studies to see if Vitamin D can prevent Flu
Here are links to two interesting articles:

August 2009-Vitamin D3 deficiency and its role in influenza
Sept 2009-More on Vitamin D3 and influenza

If these links donât work you can go to www.vitaminD3world.com and click on âIn the newsâ to find the articles.

Testing for flu types has increased by at least an order of magnitude meaning that there will be more people confirmed with flu simply by that... including fatalities. There is no control group so increasing graphs are not reliable evidence.

I emailed the authors of the Aus/NZ paper in JAMA asking for a breakdown of ARDS/viral pneumonitis cases... they said they didn't know... therefore much of what was reported on this paper is unscientific.

The fact is that every year winter ills place a strain on the health system... this year in Aus/NZ there were no code purples issued... that has not been the case in previous years.

Ron: The assumption is that winding up in the ICU because of influenza infection will carry a tag of "viral pneumonitis," which is a reasonable assumption. So the issue of whether there is increased flu in general is not germane. We are talking about admissions to the ICU for flu, not in the general public. So there were probably cases of viral pneumonitis admitted this year that were not counted because they were not confirmed as influenza. What the authors of this study did seems reasonable to me and to call the 15x figure a "myth" and "totally false" does not.

I thought you and your family already had the swine flu. You still think you need the vaccine?

In my opinion the billions wasted on vaccines could have saved more people by being spent on nutritional programs for the poor. This pandemic seems almost harmless compared to the poverty around the world. Also consider the fact that the same people who won't ever get a vaccine can't afford enough food to eat. Why should the fat and happy in the rich countries use up all the vaccines when they don't need them.

Revere, the paper stated that 48% had acute respiratory distress syndrome (ARDS) OR viral pneumonitis. I emailed the authors and asked for a breakdown of the number of ARDS cases... the reply I got said noone kept the breakdown. So it is a fact that considerably more than 50% of cases were NOT viral pneumonitis.

The 15x figure is therefore false. The authors compared apples and oranges. They compared viral pneumonitis from previous years with VP AND ARDS this year but are unable to differentiate the two.

The key finding in the big picture of things is that ICUs coped well in the southern hemisphere.They were busy, but at a peak day of 7 patients per million population were not overloaded. Some local area were, as in Manitoba, but that is always the case. A severe bus crash overloads local systems.

Snowy, I happen to agree with revere on this: that if you don't like AS03, you won't like MF59 either. The data on both are just as incomplete, albeit in different ways.

Revere, I just wanted to say thank you for this. I was noticing a lot (a LOT) of bad and mis- information floating around on Facebook (and other places) in the past few days, and I posted this article, hoping people would understand why the vaccine matters. At least 5 of my friends have re-posted it, and a number of people have told me it cleared up questions for them. Sites like flu.gov are great, but this article (and another at SBM) really laid it out. Thank you, again!

Oh, that appeal to authority fallacy appears over and over again. Medical doctors are expert in whatever it is they do all day. Very,very, very few doctors are experts on viruses and vaccines and infectious diseases; they don't have the credential or work experience. So if they aren't an expert, their independent opinion on vaccination doesn't deserve much more deference than of a mechanic.

I am, of course, making the assumption that these reports that doctors won't get vaccinated are accurate. So that needs checking.

So now I get it. Normally the 60+ age group is the hardest hit by the seasonal flu suffering about 90% of the totals flu related deaths with 30,000 to 35,000 dying each year in the US. The rest of the population is not nearly as affected as the 60+ group.

But the swine flu seems to infect people without regard for age so more "younger" people are dying than the average for the yearly seasonal flu.

So now people are getting more concerned because it is not just the 60+ population that is at high risk and have over reacted in proclaiming there is a pandemic. So far this year there has been a little over 6,000 deaths from the swine flu as compared to 250,000 - 500,000 deaths from the seasonal flu each year. So 6,000 deaths is a PANDEMIC?!

The CDC Government Position on Seniors and the Flu
The Seasonal Flu and Seniors
For older adults, the seasonal flu can be very serious, even deadly.
â¢Each year in the U.S., an average of 36,000 people die and more than 200,000 are hospitalized from serious flu complications.
â¢Ninety percent, 90%, of flu-related deaths and more than half, 50%+, of flu-related hospitalizations occur in people age 65 and older = 32,400 die & over 100,000 hospitalized.

â¢Research shows that 30 percent of all Americans age 65 and older don't get an annual flu vaccination.
Getting vaccinated means not only protecting yourself, but not spreading the flu to your spouse, children, or grandchildren. CDC recommends getting the vaccine as soon as it becomes available in your community because it takes the body about two weeks to build up immunity.

H1N1 Flu and Seniors
H1N1 flu is a new flu virus that is spreading in the United States and throughout the world. It is contagious and spreads from person to person. Like seasonal flu, illness in people with H1N1 flu can vary from mild to severe.
Recent studies have shown that about a third of adults 60 years of age and older may have some level of immunity against the H1N1 flu virus.

So now you know the governmentâs position, HOWEVER â¦.

IF you assume that, in fact, 33% of 60+ mature adults do have FULL immunity, and the rate of infection is the SAME as the typical seasonal flu, then at least 20,000 60+ adults will die from the Swine Flu.

In fact, probably less than 33% of the 60+ adults have full immunity and the rate of infection will likely to be higher for the swine flu, so this simplified estimate probably is a significant UNDERESTIMATE and that well over 20,000 60+ adults WILL die from the Swine flu.

On average, 92 children die of the flu each year, then an increase of over 20,000% would have to occur for a similar number of children to die of the flu as that is to be expected for 60+ adults!

So explain to me again, why are 65+ adults not at high risk, are relegated to a low priority group and rationed to get the swine flu vaccine?

By James Nicol (not verified) on 31 Oct 2009 #permalink

James: We are at the end of the line because there is a shortage of vaccine and the highest risk groups are ahead of us. In terms of risk (not numbers) the highest risk are the under 2 year old group. Pregnant women have special status in society, and those with underlying medical conditions are also at high risk. As someone in the last priority group, I don't have a problem with this.

Thank you, James (re no. 52). I've felt quite alone in bringing this matter up. Like Revere, I find myself in this last-priority group; however, I do have a problem with the discrepancy between the risks this group runs with 2009h1n1 flu, and the group's last-in-line priority. As Revere pointed out awhile ago, the epidemiological figures (at least re who falls at all ill with this flu) may well indicate a higher degree of immunity among seniors than does the serology studies result of 33 percent immune; but the issue remains of what happens to those seniors who do fall ill. And the CDC's figures last week showed that, of the 1000 U.S. deaths since April from this flu (lab-confirmed), 7 percent (about 70) were seniors and 95 (9.5 percent)were children; if the numbers of seniors and of children (in the given age ranges) in the U.S. are at all alike, this epidemiology would appear to indicate that, re risks of (hospitalization and) death from the 2009h1n1 flu, seniors' risk is not much lower than that of children (over age 2). It is noble to say, as one senior did recently, that having lived many years, one is ready to go last in line; it is less noble to force persons into that place, as if their risk were less, when relevant data appear indicating a considerably more equal risk. It is true that Bruce Gellin, interviewed by DemfromCT on Daily Kos several days ago, stated that seniors "can" get the vaccine [i.e., are not excluded] and should discuss whether to get it with their physician--but how many physicians, with an MD from NoName U. and a practice in Dinky Community HealthPlans out in Nowhere Corners, are going to "discuss" alternatives to the CDC's unchanged guidelines? At 10,000 doses per week, the 65+ group will be getting vaccine approximately sometime in February, when we may well be into Wave 3.

As far as I understand, the main argument for taking the swine flu vaccine in its current form is to avoid further spreading of a mildly virulent new flu strain, and hopefully confer potential immunity in the case that new, more virulent strains develop. Like some of you may know, it was the second wave of the 1918 swine flu virus that caused most fatalities. How likely is such a "second wave"? I feel that principle should guide whether to take the vaccine or not, since in its current form it does not seem to pose much of a threat.

I'm sorry for asking this but me and my partner live in Sweden and are debating whether to take the government administered vaccine or not. As it has been said, it DOES contain adjuvants, and it was indeed approved as an emergency measure by special decree that bypasses the otherwise usual safety standards.

I'm confident that the author's opinion is correct regarding the negligible safety concerns of adjuvants, but then again hastily produced vaccines inspire concern as the hastily produced 1976 swine flu vaccine in the US did have lethal unknown side-effects, albeit for different reasons.

So, hastily conceived vaccine against a new flu strain that might or might not develop into a deadlier strain. As an expert, is the trade off worth it and would the current vaccine even be effective against all forms of future swine flu for that matter? Thank you for your help.


By Matias Otero (not verified) on 04 Nov 2009 #permalink

I have seen endless reports from epidemiologists like the one above.

But I have yet to find stats that show the age groups of those affected by the vaccinations. Recently there have been deaths linked to the swine flu vaccination, but they have been - as far as I have read in the newspapers - almost solely amongst older people (and w/ pre-existing health conditions in many cases).

So, as a 29 y/o who travels very frequently from Europe-Asia-US, and is often in university-settings, I am very high-risk at getting the swine flu. I would like to get the vaccination and if it seems to only have been affecting an older population, then it seems very low risk to me. But I need these numbers before I can make a decision...can anyone help me w/ this???

If so, please email me at whyislinda@gmail.com, I would be so grateful!!! I can't get answers anywhere!!! :-(