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This is partly because, when making flu vaccines, health authorities and flu vaccine manufacturers have to predict which strains of viruses are most likely to hit in a particular year. They then produce the flu vaccines accordingly. At best, they can cover about 70 percent of common flu viruses. But sometimes, they can be way off the mark.
In 2004, the US Centers for Disease Control and Prevention (CDC) reported that the year’s flu vaccine had "no or low effectiveness" against influenza or influenza-like illness. Depending on how the data were analyzed, the vaccine protected from zero percent to 14 percent of study participants.
What if, in the case of the H1N1 vaccine, it is manufactured for a known virus such as H1N1? Will it be more effective? As you will see later in this article, the answer is still NO,
But first, let's hear from some notable experts about flu shot effectiveness in general:
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The late Dr Graeme Laver, former Professor of Biochemistry at the Australian National University, was a co-inventor of the flu vaccine and also of the anti-viral drug, Relenza. In November 2007 Dr Laver was quoted by several UK newspapers saying he was never really impressed about the efficacy of flu vaccines. He said: “It is better to do nothing, and I wouldn’t want to advise people not to take it, but you can’t rely on it doing any good.” Another notable expert is Dr. Anthony Morris, a distinguished virologist and former Chief Vaccine Control Officer at the U.S. Food and Drug Administration (FDA). He said: “There is no evidence that any influenza vaccine thus far developed is effective in preventing or mitigating any attack of influenza,,, The producers of these vaccines know they are worthless, but they go on selling them anyway.” |
Flu shot effectiveness - what the vaccine package inserts say
For information about the effectiveness of specific vaccines, a good source of information are the vaccine package inserts. These are detailed documents, for doctors and other healthcare professionals, with instructions on usage, information about the ingredients used. vaccine side effects, studies done, contraindication - who should not receive the vaccine etc. They also includes information about the specific flu shot effectiveness.
Vaccine package inserts are normally available only to doctors and in the past, patients never got to see them. So in the past, the public would not have known, for example, that a vaccine had not been tested on pregnant women and if government health authorities highly recommend it for pregnant women, the public simply assumes that the appropriate tests had been done and that the vaccine had been proven to be safe.
With the Internet, it is easy to access the full text of vaccine package inserts. We know otherwise. We know, for example, that the H1N1 vaccine has NOT been tested on pregnant women. Perhaps the only thing we still do not know is WHY this vaccine is still being recommended for pregnant women - in fact they are often given priority!
With regards flu shot effectiveness, the information provided in vaccine package inserts is shrouded in medical jargon and some explanation is needed for ordinary folks to understand what it really means. But even without the additional explanation, the raw figures are not too impressive.
The vaccine package inserts (for H1N1 vaccines given via injections) usually state following:
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Specific levels of HI antibody titers post-vaccination with inactivated influenza virus vaccine have not been correlated with protection from influenza virus. In some human studies, antibody titers of 1:40 or greater have been associated with protection from influenza illness in up to 50 percent of subjects. |
Without fully understanding the medical jargon, this seems to imply that the flu shot effectiveness rate is only "up to 50 percent". Not very impressive is it? And if you have ever been attracted by "Sale" advertisements proclaiming discounts of "up to 50 percent" you will know that "up to" very often means "less than". The term "up too" defines the maximum, not the standard.
But let's look a little closer at the above statement from vaccine package inserts. The term "antibody titers" refers to the concentration of antibodies that develop following vaccination. It means if the vaccine is 100 percent effective, it will produce antibody titers of 1:40 or greater. And that would protect 50 percent of people against the flu.
BUT... no vaccine is 100 percent effective. The vaccine package insert from Australia vaccine manufacturer CSL, for example, states that their H1N1 vaccine produces the desired titer rates for only:
Putting together the two pieces of information, you will realise that the true flu shot effectiveness rate is only "up to" (meaning "less than") 50 percent of 48.7 percent for people age 18 to 65. In other words, it is less than 24.35 percent. For those 65 years and older, the actual flu shot effectiveness rate is only "up to" 50 percent of 34 percent, meaning "less than" 17 percent.
So you see, even when flu vaccines are specifically produced for a known virus, they are not all that effective. And this is yet even considering that the virus might mutate into a form that is resistant to the vaccine.
Is it worth the risk of flu vaccine side effects, just for this small possibility of protection against the flu?