 2009 Monovalent Vaccine)
Influenza A (H1N1) 2009 Monovalent Vaccine
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Every year around this time, 120 million Americans roll up their sleeves to get their annual flu shots. Since 2010, the U.S. Centers for Disease Control and Prevention has recommended yearly jabs for every healthy American over the age of six months. The goal is to curb the spread of infection and minimize the risk for potentially dangerous complications such as pneumonia, particularly among the elderly and the very young. But science on the vaccine’s efficacy is scant among those two vulnerable groups. And although healthy adults do get some protection, it may not be as robust as they expect.
One oft-cited claim, based on several large meta-analyses published more than a decade ago, is that seasonal flu shots cut the risk of winter death among older people by half. But the research behind that claim has been largely debunked. A 2005 study published in the Archives of Internal Medicine noted that influenza only causes about 5 percent of all excess winter deaths among the elderly—which works out to one death from flu per 1,000 older people each season—so it’s impossible for the shot to prevent half of all their winter deaths. The following year, a study reported that as vaccine coverage increased among the elderly in Italy in the late 1980s, there was no corresponding drop in excess deaths. In another 2006 paper, Lisa Jackson, an infectious disease epidemiologist at the Group Health Research Institute in Seattle, and her colleagues showed that although vaccinated seniors were 44 percent less likely to die during flu season than unvaccinated seniors were, the vaccinated ones were also 61 percent less likely to die before flu season even started. “Naturally, you would not expect the vaccine to work before the thing it protects against is going around,” says Lone Simonsen, a research professor in global health at George Washington University and a co-author of the 2005 study in the Archives of Internal Medicine.
Researchers now attribute these odd findings to a “healthy user” effect. People who don’t get vaccinated often “are the most frail or [those] whose health has gone down dramatically in the last few months,” explains CDC epidemiologist David Shay. People who choose to get flu shots, in other words, are already healthier and therefore the least likely to die.
So how much does the vaccine truly help older people? In January 2012, Michael Osterholm, an epidemiologist at the University of Minnesota’s Center for Infectious Disease Research and Policy, and his colleagues published a meta-analysis in The Lancet Infectious Diseases that analyzed the results of all randomized controlled clinical trials conducted between 1967 and 2011 on the effects of flu shots. It found that there have been no clinical trials evaluating the effects of the traditional flu vaccine in the elderly. The only vaccine shown to protect against infection or death in older adults, it said, is the live-attenuated vaccine—an inhalable vaccine that contains a live, modified version of the virus—which is not approved in the U.S. for adults over age 50.
The traditional vaccine may not work so well in older people because of an idea known as immune senescence, which posits that as people age, their immune systems weaken, resulting in poor vaccine response, especially to inactivated strains. Although the U.S. Food and Drug Administration licensed a high-dose vaccine for seniors in 2009 that could theoretically overcome this problem, no studies have yet been published on how effective it is. “The higher dose produces a higher level of antibodies, but we don’t really know what that correlates to,” says Jackson. A 2010 systematic review published by the Cochrane Collaboration, an independent, nonprofit organization that promotes evidence-based medicine, concluded that “until such time as the role of vaccines for preventing influenza in the elderly is clarified, more comprehensive and effective strategies for the control of acute respiratory infections should be implemented.”
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Add Comment"One oft-cited claim, based on several large meta-analyses published more than a decade ago, is that seasonal flu shots cut the risk of winter death among older people by half. But the research behind that claim has been largely debunked. A 2005 study published in the Archives of Internal Medicine noted that influenza only causes about 5 percent of all excess winter deaths among the elderly—which works out to one death from flu per 1,000 older people each season—so it’s impossible for the shot to prevent half of all their winter deaths."
Reply | Report Abuse | Link to thisThis 'debunking' at least as stated here makes no sense. Saying that something halves your risk of death is not the same as saying that it prevents half of deaths. Even a single person can halve their risk of death. You don't need two people for that. For example, if I flip a coin before committing suicide, and only go through with it if I flip heads, then using the coin has halved my risk of death, and I am only one person. Also the '1 per 1000' formulation is arbitrary, one could just as easily say '2 per 2000' and then it is very easy to see how halving the risk will likely work out. I really doubt that this can truly be the basis on which anything was 'debunked'.
The point is that if influenza accounts for 5% of excess winter deaths, then even a 100% effective influenza vaccine cannot halve your risk of death.
Reply | Report Abuse | Link to thisThis is what the meta-analysis concluded:
"Influenza vaccine was effective in reducing influenza-like illness by 35% (95% confidence interval (CI) 19-47%), hospitalization for pneumonia and influenza by 33% (CI 27-38%), mortality following hospitalization for pneumonia and influenza by 47% (CI 25-62%); and mortality from all causes by 50% (CI 45-56%)."
Oh goodie ! I just got my flu shot yesterday; double strength as I'm 70. Spent last night under lots of cover as it felt like I had fever. So today we get the news that it may all be for naught. Joking. I'm a believer as I'm pretty sure I've never caught the flu in a year where I got a flu shot. This article belongs in the comment section of the recent article by Otto about antiscience, as announcements like these provide fodder for those who would like to claim we shouldn't trust science or vaccines. "The bring out your dead" scene from Monty Python's Holy Grail would have been all too common before modern science/medicine.
Reply | Report Abuse | Link to thisMaybe the effectiveness in elders is the immune challenge.
Reply | Report Abuse | Link to thisOTOH, this is an article that speculates a lot and says. little except that "in the absence of evidence any theory is true and false".
Those who accept whatever the drug companies say about vaccines safety and effectiveness are in fact not being empirically logical. Rigged studies are the rule with the for profit pharmaceutical industry. Vaccines can be made as individual units without neurotoxin chemical preservatives. In fact the rich can get individual unit vaccines being made in small batches in Europe without neurotoxins.
Reply | Report Abuse | Link to thisHow well flu vaccines work can vary significantly from season to season, depending on how well-matched vaccine viruses are to the viruses that are spreading that season and who is being vaccinated. In general, the flu vaccine works best among young healthy adults and older children. Some older people, children younger than 2 years and people with certain chronic illnesses might develop less immunity than healthy young adults after vaccination. Scientists and manufacturers are working to produce better vaccines. However, existing scientific evidence supports the benefits of vaccination with current influenza vaccines for these groups of people, especially during years when the vaccine is well-matched to circulating viruses. Any suggestion that people should not get a flu vaccine does a disservice to public health. Flu is a serious disease that places a significant burden on the nation’s health in the form of illness, hospitalizations and deaths. There is broad agreement in the public health and scientific community that while better flu vaccines are needed, a yearly seasonal flu vaccine is the best preventive method we have against influenza at this time.
Reply | Report Abuse | Link to thisDr. Dan Jernigan
Deputy Director
Influenza Division
National Center for Immunization and Respiratory Diseases
The Centers for Disease Control and Prevention
As executive director of Families Fighting Flu, a non-profit organization comprised of families who have first-hand experience with and many who have lost children to the flu, I urge readers to look at
Reply | Report Abuse | Link to thisall of the many years of research that support flu vaccination for everyone 6 months and older. Data just released last week by the CDC at a national infectious disease conference shows how deadly the flu can
be to children. If the data is not enough of a reason, visit our website at www.familiesfightingflu.org to learn about those families who, over the course of days, went from watching their children learn to walk, at basketball practice or dance lessons, to planning their
funeral.
There are no dangers associated with the flu vaccine, but there are very real dangers if you choose to skip vaccination. Please protect yourself and your children and get vaccinated for the flu every year.
Check out some of the Antiviral Diets that can protect seasonal flu :
Reply | Report Abuse | Link to thiswwwdotmadezeedotcom/foods-antiviral-diets-to-fight-seasonal-flu-viruses/
The article comments that is is difficult to do an ethical test for new procedures because of the risk to the unvaccinated. Here's an approach:
Reply | Report Abuse | Link to thisfor the elderly, compare morbidity/mortality for the following groups:
>>just the current seasonal flu vaccine at dose for the elderly, as now
>>current seasonal flu vaccine plus flu mist (the one given to children)
Where are these vaccines being made? And who is making them? Are they artificial? What are the natural, God given remedies and preventative measures we can take to put a snap to poking each other with retail?
Reply | Report Abuse | Link to thisI definitely think the pharmaceutical companies are pushing this. I have worked in a hospital over the last 24 yrs and have seen a huge surge in patients with MRSA, usually meaning they have run through the complete cycle of anti-biotics currently available. These people now have a compromised immune system. Part of the reason for this is the push by drug companies over the past few decades to use anti-biotics even though they weren't always necessary...And physicians all bought into this idea, not considering the long term effects. Now, the influenza issue has been another boon for the industry.
Reply | Report Abuse | Link to thisThe sources of study were cited by the journalist of this article. The point of being a skeptic is to accept evidence despite your belief. If you happened to not have had the flu without flu shots or with flu shots, it can't be attributed to any single testimonial or claim. But, a peer reviewed study is to falsify all hypothesis or claims thereof, so that when you get the results, they don't lie. Therefore, studies show that you do not decrease your chance of death from the elderly, who by nature, have less of an efficient immune system than their younger counter-parts. Just accept the studies or stop pretending that its conspiracy theory if you can't accept peer review.
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