February 1st, 2018


Even though we’ve covered this territory before on The PediaBlog, today we’ll let family physician Gretchen Lasalle, M.D. separate fact from fiction regarding flu vaccines. On her excellent blog The Adventures of Doctor Mom, Dr. Lasalle challenges this common misconception first:

“The flu shot causes the flu.” This, my friends, is false. The flu shot is a killed virus vaccine and, as such, cannot cause the illness it is meant to protect against. Live attenuated virus vaccines can make those with a suppressed immune system ill but not killed virus vaccines like the flu shot. “But I felt so cruddy after the shot”, you say. It is not uncommon to feel a bit under the weather after the flu shot – or any shot, for that matter. A bit of achiness, mild fatigue, even low grade fever is considered a normal response and is just your body’s immune system kicking into gear. It is NOT the flu. Trust me. The flu is much worse. Scenario #2: It takes 2 weeks before the flu shot even works and it is possible to be exposed to and contract the flu in that 2 weeks when you are not yet protected. This is why it is SO important to get your flu shot in the early fall. That way, by the time we see the flu in the winter months, your immune system is ready for the fight.


On Monday, we noted that even though this year’s flu vaccine is estimated to only be 30% effective, it’s still important to get one. Dr. Lasalle agrees:

“The flu shot is not that effective. It won’t help me anyway.” Au contraire, mon frere. Even though the flu shot is the “best guess” for what strains will be circulating that year and is not always spot on, it still protects you from serious complications of the flu… The Centers for Disease Control (CDC) looked at all of the pediatric deaths during the 2012-2013 flu season and found that 90% of these deaths had been in children not vaccinated for the flu. And, since the flu vaccine was introduced in 1933, we have not seen a flu pandemic such as the 1918 Spanish Flu that killed nearly 50 million people. The flu vaccine works. Moving on.


We’ve also seen that being healthy doesn’t guarantee anything:

 “I’m Healthy. I don’t need a flu shot. I’ll get over it.” Well, maybe…


Here’s an oldie but goodie:

“I prefer to get my immunity naturally.” Nope. Doesn’t work that way with the flu. The flu strains change each year. Having the flu one year does not prevent you from getting the flu the next year.


And then there is this fact:

There is NO mercury in the flu shot unless you are getting a vaccine drawn from a multi dose vial. And if you are getting your vaccine from a multi dose vial, the amount in one pediatric dose is equivalent to eating one 3 oz can of tuna fish. Not so scary is it? Also, the type of mercury in that multi dose vial is Ethyl mercury (like my sweet aunt Ethyl, not dangerous at all) which is cleared much more rapidly and is less harmful than Methyl mercury (the kind found more commonly in that can of tuna).


Read more from “Vaccine 101” at The Adventures of Doctor Mom here.


*** On January 22, 2018, Pediatric Alliance and our pediatric colleagues from around the United States began participating in an 8-week AAP-sponsored immunization advocacy campaign on social media. Please follow all our social media posts during this project on Facebook and Twitter.


(Google Images)


3 Responses to Separating Flu Fact From Fiction

  1. I think that repeated influenza infection or vaccination year after year or even repeated exposure (as is the case with medical professionals)could offer some CROSS-immunity and partial protection this year. As one becomes elderly and debilitated, this potential benefit likely wanes.
    I wonder if the double-strength flu vaccine given to the elderly this season has been more protective to date than the regular vaccine.

    • I didn’t know that the elderly were getting a double-strength dose. My dad is 90 and did get a vaccine at a pharmacy. Did all places give double doses or just doctor’s offices?

      • This according to the CDC:

        “The CDC and its Advisory Committee on Immunization Practices have not expressed a preference for any flu vaccine indicated for people 65 and older. CDC recommends flu vaccination as the first and most important step in protecting against the flu.”

        Because of the lack of a specific endorsement from the CDC, I suppose not every person 65 and older is getting, or even being offered, the stronger vaccine.

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    Ned Ketyer, M.D.

    Ned Ketyer, M.D.

    Dr. Ketyer has special interests in developmental pediatrics and preventative medicine, specifically how nutrition and the environment affect health. He earned his bachelor’s degree from the University of Vermont and his medical degree from Northwestern University Medical School. He completed his residency at Children’s Hospital of Pittsburgh.

    As one of the founding physicians of Pediatric Alliance, PC, Dr. Ketyer served as its president from 1997-2004. He has been practicing general pediatrics at Pediatric Alliance since 1990. Dr. Ketyer and his wife have three boys and live in Pittsburgh's South Hills. 

  • Note: The information included in these posts is for educational purposes only. It is not intended nor implied to be a substitute for professional medical advice.

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