The "Autism and Flu Correlation" study and its inevitable use in marketing the flu shot.

By now, you’ve probably seen the news articles, like this one, reporting on the Danish study published in Pediatrics that found “that maternal influenza infection was associated with a twofold increased risk of infantile autism” and that “prolonged episodes of fever caused a threefold increased risk of infantile autism.”  You’ve probably already been told that this is even more reason for pregnant women to get their flu shots.

While I am not a doctor, I do want to make sure that, if you are pregnant, you are armed with all of the facts to make an informed decision.  Somewhere along the way, informed consent kind of fell to the wayside.  We, as patients, are regularly not given all the information needed to give “informed consent.”

As you consider whether or not to get the advised flu shot if you are pregnant, please take some time to consider other points.

Avoiding the Flu in General

Let’s just say that getting the flu and other illnesses is the cause of autism, and ignore the fact that the flu has been around as long as we can remember and autism at the rate we are seeing is a new concern for humankind…

In the Huffington Post article,  Catherine Pearson wrote, “The Centers for Disease Control and Prevention recommends a flu shot for everyone who is at least six months old, and includes pregnant women on its list of people for whom vaccination is particularly important.” And that’s totally true; the CDC does say that. But there’s also  plenty of evidence to suggest that getting enough vitamin D would be a good idea to avoid getting the flu, but neither the CDC or the media reports about this Danish study are making that suggestion, even though patients are supposed to be making informed consent when getting vaccinations, not just consent.

FOOD FOR THOUGHT: Compare how often have you been offered a blood test to check for vitamin D deficiency to how often you’ve been offered a flu shot?

I explain the relationship between the flu and vitamin D connection in a previous post if you don’t know why I bring this point up.

It’s also important to remember that getting the flu vaccine isn’t necessarily going to protect a woman from getting the flu. No for real.  There’s many variables including your own health, the particular strains of flu going around, and much more.  The vaccines own inserts mention that it might not actually work on you anyway.

READ ALSO: Why vitamin D levels should be considered during pregnancy in general & for fetal development.

The Flu Vaccine During Pregnancy

The CDC, most US doctors and the media proclaim the flu vaccine to be safe to use during pregnancy. The CDC says that the nasal spray version of the flu shot is not to be given to pregnant women. That means pregnant women are supposed to get either the intradermal vaccine or one of the intramuscular vaccines.  Let’s look more carefully at the vaccines that are available in the US during the 2012-2013 flu season according to the CDC.

Fluzone Intradermal- Consider what the manufacture’s own prescribing information says about this flu vaccine’s use during pregnancy:

“A developmental and reproductive toxicity study has been performed in female rabbits at a dose approximately 20 times the human dose (on a mg/kg basis) and has revealed no evidence of impaired female fertility or harm to the fetus due to Fluzone Intradermal. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, Fluzone Intradermal should be used during pregnancy only if clearly needed. Healthcare providers are encouraged to register women who receive Fluzone Intradermal during pregnancy in Sanofi Pasteur Inc.’s vaccination pregnancy registry by calling 1-800-822-2463.”  NOTE: According to the CDC, the intradermal flu vaccine is not ok for anyone under 18 or over 64 either. So, pregnant teenagers would automatically not qualify for this version of the flu shot.

Fluzone Intramuscular– Consider what the manufacturer’s official FDA information says about this flu vaccine’s use during pregnancy:

“Pregnancy Category C: Animal reproduction studies have not been conducted with Fluzone. It is also not known whether Fluzone can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Fluzone should be given to a pregnant woman only if clearly needed.”

Fluvirin Intramuscular– Again, the manufacturer’s official FDA information states:

“Pregnancy Category C: Animal reproduction studies have not been conducted with Fluvirin®. It is also not known whether Fluvirin® can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Fluvirin® should be given to a pregnant woman only if clearly needed.”

Fluarix Intramuscular– Consider that the prescribing information from the manufacturer states:

“A reproductive and developmental toxicity study has been performed in female rats at a dose approximately 56 times the human dose (on a mg/kg basis) and revealed no evidence of impaired female fertility or harm to the fetus due to Fluarix. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, Fluarix should be given to a pregnant woman only if clearly needed.”

Flulaval Intramuscular– Consider that the manufacturer’s official FDA information also states:

“A reproductive and developmental toxicity study has been performed in female rats at a dose approximately 56 times the human dose (on a mg/kg basis) and revealed no evidence of impaired female fertility or harm to the fetus due to Flulaval. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, Flulaval should be given to a pregnant woman only if clearly needed.” Note: This vaccine is only indicated for people over the age of 18 as well, so pregnant teens would not be able to get this flu shot.

Afluria Intramuscular– Consider the package insert from the manufacturer states:

“Safety and effectiveness of AFLURIA have not been established in pregnant women or nursing mothers and in the pediatric population below 6 months of age.”

These are your options for the flu shot if you are pregnant. Needless to say, these facts aren’t mentioned regularly in mainstream media, but I feel that these facts are pertinent to making informed consent prior to receiving the flu vaccine during pregnancy.

Correlation Does Not Mean Causation

This autism study was  a population-based cohort study consisting of 96, 736 children aged 8 to 14 years and born from 1997 to 2003 in Denmark. Cohort studies do aid in observing possible causal associations, but determining true causality usually requires further experimental trials. The children who developed autism in this study accounted for only 1% of the children in the study. There are many factors that would need to be looked at at this point.  For example, perhaps the flu didn’t cause the autism, perhaps the flu and autism have a shared nutritional deficiency that increases the risks of both.  Perhaps they have a shared exposure to certain toxins or certain foods.

There are many variables here and the study itself explains this. Contrary to media reports, the researchers did point out that because many adjustments were made during the study and because the study relied on the mother’s answers and not their medical record, a definitive link between the flu or fevers and autism really couldn’t even be made. I am not discounting the information in this study. It’s a great tool for observation.  I just want to make sure that if you are pregnant, you see the complete picture.

Doctors are already using this study to promote getting the flu shot during pregnancy For example, Dr. Colleen Boyle, director of the National Center on Birth Defects and Developmental Disabilities who was not involved with this study commented in regards to it, “This is flu vaccine season so pregnant women should get the flu vaccine immediately.”

If you’re pregnant, you have a right to be made fully aware before giving “informed consent” during the most crucial developmental period of your child’s life.

 

Disclaimer: This article is not intended to be used as medical advice. This is not a substitute for professional medical advice or care. It is intended to be used as a tool for open discussion with your medical professional.

10 Comments

  1. leanne

    Check out the studies in Canada that took people presenting to the Emergency Room with “Influenza-Like Illness” (ILI), who then were tested to see whether they did have influenza… I would have to check the actual stats, but my recollection is more than 80% DID NOT have influenza!!! SO. Self-report of “flu” during a pregnancy a decade earlier is not that compelling to me in terms of “evidence”… The one good thing moving forward would be for this population study to justify some funding for a prospective study which actually tested not only for influenza, but any other viral illnesses that may cause fever, and test and document actual temps resulting. The viral theory behind at least a sub-group of the autisms is a theory worthy of serious study, but prospective studies with testing and evidence are needed.

    • leanne

      Okay, so I re-read the info and this time it seems like the mothers self-reported during pregnancy or peri-natally… not a decade later. STILL. With the erroneous perceptions of health care workers in the ER of “ILI” being accurate *rarely* (and clearly, if the people presented themselves to the ER, they must be the most serious cases), unless these women had swabs done, it’s not likely to any more accurate an assessment of what they are sick with than an ER doc with a patient in front of him, right? It’s like, once they started promoting “flu shots” and influenza’s profile got elevated, any time someone gets what we used to call a bad cold, they immediately think (and say) “I’ve got the flu”.

    • leanne

      OKay, here’s some current data – from last week the CDC reports that in 50 States and Puerto Rico, there were:

      3,277 specimens tested for influenza based on ILI presentation to docs
      6.9% were positive for any influenza

      Oh, and here, you can see for all the weeks from Week 40 of 2011 (Septemberish) through to the 38th week of 2012 – a whole year – you can see that out of ALL the testing done on people presenting to a doctor for help because their respiratory illness is that bad, and *all* tests for influenza must be reported for WHO tracking… so ALL the testing in ALL 50 States and Puerto Rico for a whole year… show of all the Influenza-Like Illnesses presenting for testing, the range of positive influenza specimens was 1% and the very most was about 31%, at the “peak” of flu season. Ignore the pretty colors – look at the RIGHT vertical axis and the black line:

      http://www.cdc.gov/flu/weekly/weeklyarchives2011-2012/images/image391.gif

      So. The docs were concerned enough to test because the patient was SO sick with “influenza-like illness” – and the vast majority of the time, it was NOT influenza.

    • leanne

      Also, facts like this are important to consider:

      – according to the Canadian Nosocomial Infection Surveillance Program (CNISP) during the 2010-2011 influenza season, of the adults hospitalized due to confirmed influenza, 43% had received the 2010-2011 influenza vaccine

    • Dawn

      That’s exactly what I was thinking Leanne. Like each point, I completely considered putting in there because you’ve brought them up in the various forums over time. And I kept thinking about these ponts when putting this together. But I didn’t want to rip apart the reporting method of the study too much just to keep it simple. The leap for doctors to push a vaccine during pregnancy when the manufacturer’s own reports urge caution based on a cohort study with so many variables is too great a leap in my opinion. It’s an important study that gives pause to consider all these variables, but not to start suggesting immediate flu vaccinations in pregnancy.

  2. Dawn

    ALSO important is to consider multidose or single dose vials and the levels of mercury comparatively. All of these different vaccines indicated none in the single dose, but it would still contain some sort of adjuvant and that needs to be considered during pregnancy. SImilarly, if an immune response from the flu were the autism link, they didn’t get into whether an immune response from a vaccine would do that similarly. And if so… does that indirectly link all immune responses during early development that cause fevers and flu like symptoms to autism? Like this study brings up just as many questions in the DO NOT get flu shots category as it does in the get them category and it seems highly irresponsible for the next logical jump for the media and so many doctors to have already taken this as a tool to promote flu shots.

  3. Dawn

    Another thing to consider is did they ask women if they took tylenol during their fevers and flus. That could be another factor to consider in that many people are pointing to tylenol as being a factor in this.

Leave a Reply

Your email address will not be published. Required fields are marked *