Has the H1N1 vaccine been scientifically proven to work?

**The_Absolute** · Nov24-09, 05:15 AM

Has the H1N1 vaccine been scientifically proven to protect against the H1N1 "swine" flu virus? I am very hesitant to get one as I have heard that people have developed serious side effects, such as Guillian-Barre syndrome.

**Borek** · Nov24-09, 05:38 AM

Things have to be seen in a correct perspective - side effects are extremally rare. Not that I have any data at hand, but from what I understand more people have problems because of flu complications, than because of vaccine side effects.

Not that I am going to vaccinate myself, but I am healthy, I have had no flu in the last 20 years or so, and even if I had - I had no fever nor other symptoms, so I bet I am on the safe side even without.

**jim mcnamara** · Nov24-09, 04:50 PM

All imunizations have a very small risk, so does taking any medication for that matter.
The probability of dying from H1N1 influenza is several orders of magnitude greater than the risk of problems with vaccination.

From: http://www.cdc.gov/mmwr/preview/mmwr...cid=mm5844a4_e
During August 30--October 31, 672 deaths associated with laboratory-confirmed influenza virus infections were reported to CDC through AHDRA. On average, 29 states reported laboratory-confirmed deaths each week during that period. The 672 laboratory-confirmed deaths are in addition to the 593 laboratory-confirmed deaths from 2009 pandemic influenza A (H1N1) that were reported to CDC from April through August 30, 2009.

Influenza-Associated Pediatric Mortality

During August 30--October 31, CDC received 85 reports of pediatric deaths associated with influenza infection (Figure 4). Seventy-three of these cases were associated with laboratory-confirmed 2009 pandemic influenza A (H1N1) virus. The remaining 12 pediatric deaths were associated with an influenza A infection for which the subtype was undetermined.

Now - just think if that many people had died from flu vaccination - don't you suspect it would have been all over the real media?

**Moonbear** · Nov24-09, 05:22 PM

Originally Posted by jim mcnamara

All imunizations have a very small risk, so does taking any medication for that matter.
The probability of dying from H1N1 influenza is several orders of magnitude greater than the risk of problems with vaccination.

Now - just think if that many people had died from flu vaccination - don't you suspect it would have been all over the real media?

Two problems here. First, you're comparing apples and oranges...risk of death from influenza to risk of any complications from vaccination. Second, the relative risk depends on a variety of factors such as age and pre-existing health conditions. If you're a healthy, young, non-pregnant adult, your risk of complications from the vaccine are greater than from flu. That changes if you are pregnant, very young or very old, have an immune deficiency, are a smoker, have a history of asthma, etc. And, in those cases, the risk also depends on the version of vaccine you get.

But, none of that relates to the question the OP is asking, which is whether there is sufficient evidence that this year's H1N1 vaccine is actually working to prevent people who have been vaccinated from catching H1N1. It's a reasonable question, because there have been instances in the past when flu vaccines have not worked, particularly if the strain started mutating between the initiation of vaccine development and actual distribution of the vaccine. And, there are always unknowns with a new virus strain.

And, since its also possible to get very mild flu symptoms from the H1N1 virus, there may also be segments of the population who have already had it, are immune to it, but didn't know it, so might credit the vaccine with being preventative when it really is that they already had immunity.

The reality is that since the vaccine is only recently being distributed, there won't be data on that yet. We won't know until it's been out long enough to compare the vaccinated to unvaccinated populations for incidence and severity of flu to know if the vaccine worked. But, that's nothing special about this year's vaccine.

The bottom line is that if you're in a high risk group, or if you're just one of those people who gets laid out flat by flu when you've had it in the past, or can't afford to miss even one or two days of work due to illness, it's worth getting the vaccine. If you're not in any high risk group, tend to get very mild flu symptoms when you've had flu in the past, and have enough sick days if you do get flu, then it's more a personal choice about how you feel about it.

I didn't get vaccinated because I'm almost positive I already had H1N1 this summer and decided to take my chances. My students have been spreading it around, and it seems to have hit its peak in the last two weeks, and I still haven't caught it, so I think I probably guessed right about having already had it and being immune to it. In my case, having already had it (or being pretty sure I did), I would be more worried about adverse reactions to the vaccine from re-exposure to the virus.

**russ_watters** · Nov24-09, 08:05 PM

Originally Posted by The_Absolute

Has the H1N1 vaccine been scientifically proven to protect against the H1N1 "swine" flu virus?

Yes.

**denverdoc** · Nov24-09, 09:03 PM

Originally Posted by The_Absolute

Has the H1N1 vaccine been scientifically proven to protect against the H1N1 "swine" flu virus? I am very hesitant to get one as I have heard that people have developed serious side effects, such as Guillian-Barre syndrome.

Not to my knowledge. The G-B syndrome was a very rare side effect associated with the swine flu vax of the 70's. A colleague of mine who is an ER nurse shared a case she saw recently here in Albuquerque--otherwise healthy 18 y.o male who presented to the ER with fever and shortness of breath. Had been seen by his primary doc a few days before and given Tamiflu. 24 hours within presenting to the ER, he was dead. More tamiflu resistant cases have been reported. This is bad news. It is ironic that the single most cost effective public health measure of vaccination is met with such skepticism. In the 70's the first swine flu scares was a mistake. But 30 years later and an explosion of understanding re genetics/molecular biology later, vaccines remain king in bang for buck.
I was swined 3 weeks ago--miserable for a few days. So if you're healthy and in none of the high risk categories, likely not a life changing event either way.

~~Sorry!~~ · Nov24-09, 09:29 PM

Originally Posted by Moonbear

Two problems here. First, you're comparing apples and oranges...risk of death from influenza to risk of any complications from vaccination. Second, the relative risk depends on a variety of factors such as age and pre-existing health conditions. If you're a healthy, young, non-pregnant adult, your risk of complications from the vaccine are greater than from flu. That changes if you are pregnant, very young or very old, have an immune deficiency, are a smoker, have a history of asthma, etc. And, in those cases, the risk also depends on the version of vaccine you get.

But, none of that relates to the question the OP is asking, which is whether there is sufficient evidence that this year's H1N1 vaccine is actually working to prevent people who have been vaccinated from catching H1N1. It's a reasonable question, because there have been instances in the past when flu vaccines have not worked, particularly if the strain started mutating between the initiation of vaccine development and actual distribution of the vaccine. And, there are always unknowns with a new virus strain.

And, since its also possible to get very mild flu symptoms from the H1N1 virus, there may also be segments of the population who have already had it, are immune to it, but didn't know it, so might credit the vaccine with being preventative when it really is that they already had immunity.

The reality is that since the vaccine is only recently being distributed, there won't be data on that yet. We won't know until it's been out long enough to compare the vaccinated to unvaccinated populations for incidence and severity of flu to know if the vaccine worked. But, that's nothing special about this year's vaccine.

The bottom line is that if you're in a high risk group, or if you're just one of those people who gets laid out flat by flu when you've had it in the past, or can't afford to miss even one or two days of work due to illness, it's worth getting the vaccine. If you're not in any high risk group, tend to get very mild flu symptoms when you've had flu in the past, and have enough sick days if you do get flu, then it's more a personal choice about how you feel about it.

I didn't get vaccinated because I'm almost positive I already had H1N1 this summer and decided to take my chances. My students have been spreading it around, and it seems to have hit its peak in the last two weeks, and I still haven't caught it, so I think I probably guessed right about having already had it and being immune to it. In my case, having already had it (or being pretty sure I did), I would be more worried about adverse reactions to the vaccine from re-exposure to the virus.

Moonbear I have to disagree here, it is true in some cases that vaccinations can lead to serious side-effects in certain individuals but here (in Ontario at least) Out of the 6.6 million doses administered there have only been 36 cases of side-effects (out of the normal range)... that's A LOT safe than the odds of having any side-effects from your regular seasonal flu shot.

Everything else you said is on point though. Nothing in science is really 'proven' however it has been scientifically shown to the best of the scientists abilities that the vaccine will be effective against H1N1. You should consult your doctor about you medical background etc. prior to getting your shot if you're worried though. They may even be able to administer it, I know where I live certain clinics with family doctors were given the vaccine to administer.

**Ygggdrasil** · Nov24-09, 10:37 PM

Perhaps it would be useful to cite the scientific literature here: http://content.nejm.org/cgi/content/full/NEJMe0908224

The article from the New England Journal of Medicine discusses the preliminary results from two clinical trials testing the efficacy and safety of the swine flu vaccine.

From the article:

The study by Greenberg et al. shows that a single dose of nonadjuvanted vaccine containing the usual 15 µg of hemagglutinin (HA) antigen is immunogenic in a high proportion of healthy young and middle-aged adults.

and from the second trial:

In the study by Clark et al., one or two doses of an adjuvanted influenza vaccine containing 7.5 µg of HA (50% of the standard dose), administered on various schedules, elicited robust antibody titers.

Finally, regarding the safety:

Both vaccines tested have generally acceptable side-effect and adverse-event profiles, with pain or tenderness at the injection site being the most common adverse event observed. The local reactions seen with the adjuvanted vaccines were moderately higher than those generally seen with nonadjuvanted vaccines. Any association of uncommon adverse events with the vaccine cannot be ascertained in studies of this size. It is reassuring that the manufacturing process for these vaccines is identical to that used for seasonal vaccines, which have a strong record of safety. Although concerns linger about the association of the 1976 swine influenza vaccine with the Guillain–Barré syndrome, the syndrome was rare, with approximately 1 case for every 100,000 persons vaccinated. The rate was even lower among persons under 25 years of age.

**ViewsofMars** · Nov25-09, 01:18 PM

Flu Vacine Facts and Myths from the Department of Health and Human Services and
Centers for Disease Control and Prevention state, “Fact: Most of the time the flu shot will prevent the flu. In scientific studies, the effectiveness of the flu shot has ranged from 70% to 90% when there is a good match between circulating viruses and those in the vaccine. Getting the vaccine is your best protection against this disease.”

http://www.preventinfluenza.org/CDC-...acts-Myths.pdf

**Moonbear** · Nov25-09, 02:33 PM

The agency is gathering information from Canadian officials about a batch of 172,000 doses of H1N1 vaccine that may have caused more allergic reactions than normal.

"An unusual number of severe allergies to the vaccine have been detected in Canada," WHO spokesman Thomas Abraham told Agence France-Presse on Tuesday.

http://www.cbc.ca/health/story/2009/11/24/h1n1-who.html

In response to national reports about allergic reactions to the H1N1 vaccine, Kendall said about one in 100,000 people have reacted poorly to the flu shot, the same rate experienced with regular seasonal flu shots.

In B.C., 18 cases of allergic reactions to the vaccine have been reported -- one person was hospitalized briefly and released. Nationally, 36 adverse reactions have been recorded, including two deaths.

http://www.vancouversun.com/health/H...279/story.html

In Canada, 250 people have died due to complications from the virus.

http://www2.canada.com/nanaimodailyn...c-e97854e6cfe7

Considering the relatively SHORT time the vaccine has been in use compared with the relatively LONG time the virus has been circulating in the wild, and without knowing how those who have died from the flu would have reacted to the vaccine, I am not willing to jump to the conclusion that the vaccination is necessarily better than just catching the flu just because other vaccines are better than catching the diseases they protect against.

I'm not even certain that you're not increasing your risk of catching flu before the vaccine has a chance to take effect just by standing in a long, crowded line of people to get the vaccine. That's not related to the vaccine itself, but more of an overall risk factor. We're not talking about some illness that is almost guaranteed to either kill you or result in severe disability, we're talking about a fairly mild version of flu that for most people is going to give you some fever and body aches for a day or two and then you'll be just fine again.

And, it's not guaranteed you'd catch the flu at all. Certainly if you never get exposed to the virus or never come down with the flu, ANY side effect of the vaccine is worse than NOT getting flu.

**Evo** · Nov25-09, 03:03 PM

One of the things they plan to do with the data that they are gathering from tracking the flu vaccines is that they are going to compare the reported "side effects" against what would happen anyway in simliar population number. For example if 1 person out of 100,000 people vaccinated dies of heart failure within 24 hours of a vaccination, how many people out of 100,000 would die anyway from a heart attack out of 100,000 in any given day. That's just an example. Are we seeing any significant increase in deaths or illnesses in the group that were vaccinated over what normally happens? I posted an article about it recently, I'll try to find it later.

**ViewsofMars** · Nov25-09, 03:52 PM

Originally Posted by Moonbear

I'm not even certain that you're not increasing your risk of catching flu before the vaccine has a chance to take effect just by standing in a long, crowded line of people to get the vaccine.

People weren't standing in line close to where I live. It was a drive through. Over 6,500 people in cars getting their shots. Yep! Cops were everywhere directing traffic.:) There have been quite a few children and adults getting the flu. (H1N1 has appeared on the scene.) Also, many people travel abroad for business. No one sits still in my area for very long whether it's for business or fun.

I've never had the flu. A family member that just returned from Cabo sneezed in my direction yesterday, and I thought to myself "flu shot". LOL!

~~Sorry!~~ · Nov25-09, 04:22 PM

Originally Posted by Evo

One of the things they plan to do with the data that they are gathering from tracking the flu vaccines is that they are going to compare the reported "side effects" against what would happen anyway in simliar population number. For example if 1 person out of 100,000 people vaccinated dies of heart failure within 24 hours of a vaccination, how many people out of 100,000 would die anyway from a heart attack out of 100,000 in any given day. That's just an example. Are we seeing any significant increase in deaths or illnesses in the group that were vaccinated over what normally happens? I posted an article about it recently, I'll try to find it later.

Yep, there have been many studies of this nature people just don't like to accept them. Most "side-effects" aren't even really known to be side-effects from the vaccine. Most of the time the two things are unrelated and just coincidental. When you have say 150 million people getting the vaccine in America(I've seen numbers indicating about half of Americans are not getting the vaccine) I think saying that some things are pure coincidence is not far fetched.

What really happens is Joe takes the vaccine and gets a cold, blames it on the vaccine telling Shelley, Shelley decides not worth risk it's (since Joe got sick from the vaccine supposedly she assumes odds are high that she may get sick from it too) and it just spreads like a wild-fire. Some people even make up side-effects and attribute it to the vaccine to try and persuade other people to not get the vaccine...

People just are against vaccinations in general(modern days), however, I remember reading a lot of reports from way back in the day when vaccinations were just making it into general populations. People were EXTREMELY grateful for them... Many diseases that killed many, many children each year were basically scratched out completely from countries... For instance I've had many older family members talk about their siblings who had died from Polio... in fact you'd probably be hard-pressed to talk to any elderly who didn't know someone directly who was effected by polio... IMO, 36 people have negative side-effects out of 6.6 million is a very good result. Regardless of if the virus wouldn't have even continued to kill that many people or if you personally wouldnt' have gotten sick yourself why should we as a country risk it at all?

**jreelawg** · Nov25-09, 04:58 PM

I just watched a little bit of C-span, and congress is speaking with the presidents of H1N1 vaccine makers about wether the FDA should approve their adjuvants.

They hope to have MF59 approved by the FDA based on the studies done under european oversight, rather than spend the money to have it tested in accordance with FDA regulations. This sounds perfectly fine to me, but the details make me skeptical.

The first reason, is that it is said that in various European countries, the adjuvant has been used for so many years, but had only been approved and used on people 65 and over.

Now the problem with this is that at age 65, your health generally begins to or is already degrading. I would like to know yet can't find the information, which countries have been participating in this, and what the average life expectancy is in each of these countries.

Now the adjuvant boosts the immune response because the oil injected into the bloodstream is attacked by the immune system aggressively, and because it is mixed with the vaccine, the anti-gen is subject to the same immune response. The concern most people who are against the adjuvant argue is that because squalene ( the active ingredient in the adjuvant) is present naturally in the body, injecting it into the blood stream and forcing the immune system to attack it, may cause the immune system to begin to attack the squalene which is naturally present in your body leading to an auto immune disorder.

For those who don't know much about these types of auto immune disorders, here is a brief
explanation from google health about Lupus,

"Causes
SLE (lupus) is an autoimmune disease. This means there is a problem with the body's normal immune system response. Normally, the immune system helps protect the body from harmful substances. But in patients with an autoimmune disease, the immune system can't tell the difference between harmful substances and healthy ones. The result is an overactive immune response that attacks otherwise healthy cells and tissue. This leads to chronic (long-term) inflammation.
The underlying cause of autoimmune diseases is not fully known. Some researchers think autoimmune diseases occur after infection with an organism that looks like certain proteins in the body. The proteins are later mistaken for the organism and wrongly targeted for attack by the body's immune system."

https://health.google.com/health/ref...+erythematosus

Lupus interestingly is also one of the very rare side effects of regular flu vaccines, and is an incurable auto-immune disorder.

Now unlike an allergic reaction, this type of reaction wouldn't necessarily show signs beyond the normal range of side effects, and would only become evident over time. For people over 65, you very well may die, or suffer other non related diseases before there is enough time for this to become evident, and many of the symptoms are similar to that which a person this age would already be experiencing due to old age. Like another example, how many people out of 100 thousand had a heart attack after the vaccine, and how many would have had one out of 100 thousand anyways, how many people over 65 would have died anyways and how many did after the vaccine? The first problem with this is that depending which country your in, your life expectancy may already be achieved at 65 leaving any data on the safety of the adjuvant limited, and hard to differentiate.

So I have a hard time with this. The fact that it was only used in vaccines on this age range and without mention of life expectancy in these countries, which is now being used as an argument that it is safe in general seams kind of shady to me.

Do you think the adjuvant should be approved and added to this years or next years batches of vaccine, or should it be subject to normal FDA testing regulations and go through the normal process. Advantages of this would be cheaper vaccines, and more supply. Disadvantages would be the undermining of regulations put in place to protect the health of the public.

**Evo** · Nov25-09, 07:08 PM

The link I originally posted is gone, but this has some of the same information.

They found that in Britain, for every 10 million people who might get the swine flu shot, about 22 cases of Guillain-Barre syndrome and 6 unexplained deaths will likely occur within 6 weeks of vaccination — and probably won't be caused by the vaccine.

http://www.msnbc.msn.com/id/33552662...-cold_and_flu/

**Count Iblis** · Nov25-09, 07:46 PM

There was a news report a week or so ago that claimed that people who took last year's ordinary flu vaccine appear to have some limited protection against Swine flu. That was based on a statistical study on US military personell.

It was theorized that this was due to priming the killer cells instead of building up antibodies. The regular flu shot also has an H1N1 variant but this is too different from the Swine flue H1N1 that the antibodies won't be effective.