Friday, October 30, 2009

more about the H1N1

I'll state a few things up front:
1- I'm not a doctor. Not even a little bit. I have a degree in Psychology that is research-based. But I have worked for a health research agency for about 4 years and I'm pretty darn familiar with the world of health research, and evidence-based medicine.
2- I believe in vaccination, however I didn't start getting the flu shot until three years ago.
3- I've never had and adverse reaction to a vaccination, nor have I had anyone close to me experience one (that I know of).
4- I can't remember the last time I got the flu, but Jordan seems to get it every year.

Ok, so now that my potential biases are out of the way, I've already posted once about the pandemic paranoia already and I've had several people ask me about the H1N1 flu vaccine. Since I do love me some are some things I think might be of interest to those of you who are trying to make a decision.

First off, the vaccine is called Arepanrix, it is manufactured by GlaxoSmithKlein, and it is Health Canada approved "based on limited testing." Health Canada has decided that the risks of an H1N1 pandemic outweigh the risks associated with the vaccine and will be monitoring the effects of the vaccine pretty closely.

It is an adjuvanted vaccine, which means that in addition to the inactivated virus matter that helps you build immunity to the flu, it also contains a substance that helps "jump start" your body's immune response. The adjuvant in this particular vaccine is made up of Vitamin E (DL-α-tocopherol), Squalene (an organic compound that is usually derived from sharks), and Polysorbate 80 (an emulsifier that is also used in foods). This is the first time (I think) that an adjuvant has been used in a flu vaccine, but it it is used in other vaccines.

The vaccine also contains the mercury-based preservative Thimerosal. Yup, mercury is poisonous and if you inhale a big old vial of Thimerosal, you'll probably die. But, the amount of mercury in your dose of the H1N1 vaccine is less that the amount of mercury in a tuna sandwich.

In general, you have a 1-2 chance in 1 000 000 of having a serious adverse reaction to the vaccine.

The "virus bits" that are in the vaccine were grown in eggs. So if you are allergic to eggs, you can't get the vaccine.  Although there is not a huge amount of data about the vaccine, it seems like it "gives you immunity" about 10 days after you get the injection. If you would like to read the product information leaflet put out by Health Canada, you can read it here: link

So now that you know a little more about the vaccine, is it worth getting it?
During normal flu season, you have about a 9-12% chance of getting the flu, although this can get up to 42% if you have young children. So far (and it is very early in the season), the "attack rate" of H1N1 is higher than the "normal" flu.

With regard to how sick you get, pretty much everyone who gets H1N1 comes down with a fever and a cough and more than half have shortness of breath. Chills, muscle soreness, runny nose, sore throat, and headache are also common. Sounds like a good time!

About 11 in 1000 cases in the US (this is the spring cases I think) were hospitalized and about 70% of people hospitalized have had pre-existing risk factors such as diabetes, heart disease, pregnancy, asthma, and kidney disease. The vast majority of people who have been determined as "confirmed or probable" cases of H1N1 are under the age of 24 (with the next highest group being from 25-49).

As of October 29th, 95 Canadians have died from H1N1 (surveillance data found here). According to a doctor of Community and Family Medicine at the University of Toronto, your chance of getting H1N1 and getting quite sick is 25% (higher if you have small children), which at first I kind of thought "well that's not too bad" but then when I converted that to 1 in 4 and pictured myself standing around with three people at work, it seemed a little worse.

So, there is pretty much a 1 in a million chance that I will have an adverse reaction to the vaccine and about a 1 in 4 chance that I'll get the H1N1 flu and will get pretty sick. I know statistics can be deceptive, but when I see those numbers and add in the fact that I have asthma...I wonder if there is really a question. On the other hand, waiting in line for 4 or 5 hours for a vaccine that may not actually protect me against H1N1 doesn't sound all that appealing.

Will I get it? I really hope so! I hope to get it next week when they've ironed some of the kinks out of the system.

Hopefully this information was helpful in at least making you feel like you might be able to make a more educated decision about whether you will or will not get the flu shot. Feel free to ask questions. I'll try my best to find the answers for you.

So- what will it be? Vaccinate or no? Or are you just not concerned?


kris said...

Did you look into the validity of the arguments for not getting it, such as the significance of how few trials have taken place?

Were the "virus bits" grown in free-range, free-run, or industrial farm chickens?

k said...

I think it IS a valid argument- we don't know for sure that it will work in everyone and it's the same thing every year with the flu shot (although with seasonal flu, we're getting vaccinated against strains that they think will be present where as with H1N1 we're getting vaccinated against a strain that we know is around). But again, most health agencies have decided that the early evidence points to it working well enough to approve it.

Then again- for the cynics out there- maybe they just want people to feel like they are doing something :)

I can see if there is anything more scientific and "learned" than my own musings though.

k said...

oh- and the virus bits are industrial, the egg matter it is grown in are free-run, and the sharks are free-range ;-)

kris said...

You should use your research skills to find out what changed 13 or so years ago that made children born since then particularly susceptible to H1N1, if that's true.

I was planning on getting vaccinated but I don't intend to wait in line for hours.

lu said...

you are the best!! you wrote this in a way that is really easy to read and is great for people like me who have not taken the time to do my own research. i realise you are not a doctor, but i do know that you are rational, intelligent, and i respect the decisions you make so for that, i am really interested in what you have had to say about this.

and regarding the issue of younger people being susceptible - i have heard that it is because we have not been exposed to similar flus so we have not built up any immunity. which raises a whole other question on whether we should be vaccinating against this now and if the next strain will have an upper hand on us next time it comes around, whenever that is.

but like i said, i have done very little research on any of this, so that opinion is admittedly ill informed.

Runner Leana said...

Thanks for your post k. I have never gotten the flu shot before and I've never really gotten the flu either. A cold yes, bronchitis yes, but that is about it.

I'm on the fence as to whether I'm going to get the shot. For sure I'm not rushing out in the next week to stand in line all day to get it. Maybe in a few weeks when there is a little less panic.

Heather said...

I still don't think I'm going to get it... I know that sounds silly with the job I have and all, but I just don't think I could be bothered to wait forever and get a flu shot when I've never had one before and I've never had the flu.

That being said, if I happened to be somewhere and there were shots offered and I didn't have to go too far out of my way, I'd get it.

Lulu said...

Thanks for the synopsis, it was really nice to read! For us in the military, I've been informed that we are being marched to the base hospital for the vaccine, and if we do not want to have we can then tell the nurse and sign a disclosure statement.
I was quite hesitant about getting it as I have never received the regular flu vaccine, but I never seem to get the flu anyways. I might just get this one though.

k said...

If you don't get the shot, your best bet is to wash those hands! Use good technique, wash for 20 seconds, and alcohol-based sanitizers are good too (although I think you need to use more than you think- apparently it should take 15-2- seconds for the sanitizer to get all rubbed in)