Friday, May 13, 2011

Flu: What are the Stats?/ CDC data

The 2010-11 flu season is now over.  Where do we stand in terms of vaccination and deaths from flu?

The influenza vaccine is said to have been a good match to the majority of strains that circulated during this flu season.

One hundred two (102) pediatric deaths were reported to CDC from the entire US for the flu season just finished.  This compares to 88 deaths for 2007-8, 133 deaths for 2008-9, 282 deaths for 2009-10 (when swine flu caused a prolonged season of influenza infection from May 2009 through spring 2010), and the aforementioned 102 deaths for the 2010-11 season just ended.  CDC reports that 51% of children hospitalized for influenza had no underlying chronic illnesses, while 49% had a preexisting chronic disease.

How many people died from influenza?  CDC reported deaths from flu in the US totalled 311.  [I am not sure if this includes pediatric deaths.]  Yet CDC claims that between 3,000 and 49,000 people die from flu in the US yearly.  Where does this number come from?  Good question.  The crystal ball is in an undisclosed location.  CDC has developed mathematical models that yield projected deaths.  But the models are never compared with real numbers (deaths associated with positive flu lab tests, for example) to see how accurate they are.

On February 24, 2010 vaccine experts voted that everyone 6 months and older should get a flu vaccine each year starting with the 2010-2011 influenza season. While everyone should get a flu vaccine each flu season, it’s especially important that certain people get vaccinated either because they are at high risk of having serious flu-related complications or because they live with or care for people at high risk for developing flu-related complications.
How many people actually received flu vaccine in the US last season?  I have had a hard time finding out the number.  More than one hundred nineteen million (119,000,000) doses of flu vaccine were distributed by CDC last year, and up to 165 million doses were made.
During the swine flu pandemic in 2009-10, I estimated (due to lack of reliable data) that between 60 and 80 million Americans received vaccine, or between 20 and 25% of the population.  It seems fewer Americans have been vaccinated since, based on media reports.  
I can't tell you how many Americans were vaccinated last season.  I cannot calculate a number needed to treat to prevent one death, but it could be one million or more.  Four hundred thirteen (413) flu deaths (pedi plus total, which may be an over count) have been documented.  We don't know the completeness of the reporting.  We don't know how many of those who died were vaccinated.  We don't know what the number of people is who have had adverse reactions to the shots, nor do we have information on the types and rates of adverse reactions.  We don't know the cost of the vaccination program, but it probably costs at least a billion dollars to cover vaccine manufacture, shipping, syringes, administration, and disposal of both syringes and mercury-containing excess vaccine, which must be treated as hazardous waste.
By the way, telephone surveys are the method used by CDC and RAND to determine how many people got vaccinated.  But flu survey responses are not accurate.  For example, 39% of adults reported getting vaccinated to RAND, but less than 25% nationally actually did.  In a survey of 400 doctors, conducted by the National Foundation for Infectious Disease, 90% reported getting vaccinated.  But other data reveal that under 50% actually do.

This year, CDC says an estimated 42.3% of Americans over 6 months were vaccinated, or about 130 million Americans.  Do you think about twice as many Americans were vaccinated for flu last year, during a mild flu season, as were vaccinated in 2009-10 for swine flu, when vaccine was hyped daily?  I think not.

It would be nice for our taxpayer-funded public health system to give American citizens (not to mention health care providers) accurate numbers so we could make an educated decision about the risks, benefits and costs of the recommended yearly flu vaccination.  But then we could perform an independent cost-benefit assessment of flu vaccine policy.  And (considering Cochrane found no clear benefit) it may turn out that this expensive program has little in the way of data to recommend it.  After all, if the benefits were demonstrable, why wouldn't the CDC tell us?

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