Thursday, January 4, 2018

Influenza Vaccine Effectiveness a ‘Dismal 10 Percent’ by Marco Cáceres

Influenza Vaccine Effectiveness a ‘Dismal 10 Percent’


Despite the predicted gross ineffectiveness of this season’s influenza vaccine, the CDC and many
doctors continue to recommend getting it based on the rationale that it’s “better than nothing.”
On Feb. 26, 2015, the Centers for Disease Control and Prevention (CDC) estimated the effectiveness of the vaccine against the predominant influenza A H3N2 viruses for the 2014-2015 season at 18 percent1 2—a level reportedly described by CDC researchers as having “little to no efficacy.” Later in 2015, the CDC adjusted its estimate for the effectiveness of the influenza vaccine that season to 19 percent.3
The 19 percent effectiveness estimate for the influenza vaccine in 2014-2015 was unusually low, even by the consistently low effectiveness standard of the annual influenza vaccines. During the previous 10 seasons, the average effectiveness estimate for influenza vaccines had been 42.5 percent.4 5 In only four of those 10 seasons had the effectiveness estimate surpassed 50 percent, and never more than 60 percent.4
In the first of those 10 seasons, 2004-2005, the effectiveness estimate was even lower than 19 percent. It was 10 percent. In other words, the influenza vaccine for that season was 90 percent ineffective.
Apart from the 19 percent estimate a few years ago, the effectiveness estimate for the influenza vaccine has not dropped anywhere close to 10 percent since 2004-2005… until this season, which was the preliminary estimate for the vaccine’s effectiveness in Australia during that country’s 2017 flu season. According to a recent article in The New England Journal of Medicine (NEJM), the effectiveness estimate for the vaccine against the influenza A H3N2 viruses during 2017-2018 might be 10 percent.”6 7 Paul E. Sax, MD of NEJM Journal Watch refers to it as a “dismal 10 percent.”8
Despite the predicted gross ineffectiveness of this season’s influenza vaccine, the CDC and many doctors continue to recommend getting it based on the rationale that it’s “better than nothing.” Dr. Sax, for example, states:
We doctors, nurses, PAs, and pharmacists can be forgiven if the weak efficacy data might take some of the energy out of our annual recommendation. But let’s try to keep giving the vaccine.8
Perhaps this mindset is best highlighted by Egypt Galloway of Wilkes-Barre, PA, who notes, “I wouldn’t say the flu shots are a bad thing because nine times out of ten it doesn’t work.”9
There are 11 influenza vaccines licensed for use in the United States,10 including:
      • Influenza (Afluria) Trivalent & Quadrivalent
      • Influenza (Fluad)
      • Influenza (Fluarix) Trivalent & Quadrivalent
      • Influenza (Flublok) Trivalent & Quadrivalent
      • Influenza (Flucelvax) Trivalent & Quadrivalent
      • Influenza (Flulaval) Trivalent & Quadrivalent
      • Influenza (Fluvirin)
      • Influenza (Fluzone) Quadrivalent
      • Influenza (Fluzone) High-Dose
      • Influenza (Fluzone) Intradermal
      • Influenza (FluMist) Quadrivalent10
The ingredients in these and other vaccines can be found on the CDC’s vaccine Vaccine Excipient & Media Summary table.11 More information about influenza and influenza vaccines, including complete copies of influenza vaccine package inserts that also list contraindications, reported reactions, results of pre-licensure clinical trials and other facts, can be found on NVIC.org.10

References:
1 Cáceres M. On the Question of Vaccine Effectiveness. The Vaccine Reaction Aug. 19, 2015.
2 Centers for Disease Control and Prevention. CDC Presents Updated Estimates of Flu Vaccine Effectiveness for the 2014-2015 Season. CDC.gov (press release) Feb. 26, 2015.
3 Ault A. CDC Says Influenza Vaccine Only 18% Effective This Year. Medscape Feb. 26, 2015.

4 CDC. Seasonal Influenza Vaccine Effectiveness, 2005-2017. CDC.gov.

5 
Fisher BL. CDC Admits Flu Shots Fail Half the Time. NVIC Newsletter Apr. 26, 2016.
6 
Paules CI, Sullivan SG, Subbarao K, Fauci AS, Chasing Seasonal Influenza — The Need for a Universal Influenza VaccineNEJM Nov. 29, 2017.
7 
Sweeney D. Health experts: This year’s flu vaccine only 10% effective. Fox 8 Cleveland Dec. 4, 2017.
8 
Sax PE. Why, Even with Depressing Predictions About Flu Vaccine Effectiveness, We Should Still Recommend and Get It. NEJM Journal Watch Dec. 3, 2017. 
9 
Blackburne C. Doctors: Get Flu Shot Despite Questions of Effectiveness ABC 16 WNEP Nov. 30, 2017.
10 
Cáceres M. Those Who Give Vaccines Should Know The Ingredients in VaccinesThe Vaccine Reaction Oct. 12, 2017.
11 
CDC. Vaccine Excipient & Media Summary. CDC.gov.

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