Showing posts with label Correlation and Causation. Show all posts
Showing posts with label Correlation and Causation. Show all posts

Tuesday, December 11, 2012

HuffPo: Anti-Vaccine Vitriol: Seeking Reason

Dr. David Katz recently published a piece on The Huffington Post in response to some of the anti-vaccination nonsense that gets posted on the HuffPo website on a regular basis.  The amazing thing is HuffPo is known to  be somewhat of a safe haven for antivaxxers, so to witness them being called out for their tactics and lunacy is nothing short of amazing.

I'd love to cite some specific passages from his article, but the truth is if I cited only the parts of the article which make sense and which make very valid points, I'd end up posting the entire piece.  Therefore I encourage you to read the entire article in its entirety over at the HuffPo website.  You can find the article at this link:  Anti-Vaccine Vitriol: Seeking Reason.

Well ok, I do have to list one of my personal favorite quotes that Dr. Katz wrote: "In other words, if you want to offer advice against vaccination that reasonable people can take seriously, try being reasonable".

I dare say the phrase "reasonable antivaxxer" is an oxymoron, but perhaps one day I'll actually come across one.  It is difficult to imagine a world where a reasonable person tosses aside all logic and common sense while ignoring mountains of scientific evidence and historical records, but perhaps there are varying levels of reason.

Of course even after reading the article, the antivaxxers once again come out in full force in the comments section.  Sadly it seems most of them were unable to complete the entire article before posting because many of their comments are using the very tactics discussed in the article itself almost as if they antivaxxers were so enraged after the first paragraph or two they skipped the remainder to cut and paste more anti-vaccine nonsense.

One comment that caught my eye was from an antivaxxer who complained of a lack of "[d]ouble-blind, randomized controlled studies" showing the efficacy of flu vaccinations.  Not only did this particular antivaxxer clearly not read or understand Dr. Katz's article, but she also appears to be very confused about ethically questionable studies.

We of course have discussed this issue in the past, and frankly anyone of average intelligence should understand the moral issues with trying to perform such a study, but even more troubling is how these antivaxxers presume it is possible to prove a negative in the first place.  I just have to wonder if someone did perform a double-blind randomized controlled study on a flu vaccine and those individuals who did not receive the vaccine were six times more likely to contract the flu - would antivaxxers actually suggest the vaccine was functioning as designed?  I think we all know the answer, and that answer is "no", because they would simply claim there was bias, or they would challenge the funding source for the study, or they would make claims about how correlation does not equal causation (even though they are guilty of confusing the two on a continual basis).

The truth is, even if the results did come out as expected it wouldn't change perceptions or the minds of the anti-vaccination crowd, so what benefit would such an unethical study provide, and at what costs?  What if one of the test subjects contracted the flu and died as a result of complications?  What if those study participants who didn't receive the vaccine contracted the flu and spread it to dozens or possibly even hundreds of others?

You see when someone doesn't receive a vaccine, it isn't only them who is impacted.  Potentially it is everyone around them.  It is anyone and everyone who comes into contact with that person which is precisely why I have no problem with calling someone who willfully skips their vaccinations out of ignorance to be nothing short of selfish.  If you want to kill yourself I have zero problem with it, but when you put the lives of others in danger due to your selfishness, then I have a problem with your actions.

We have seen the ramifications of scientific ignorance when antivaxxers refuse to allow their children to receive vaccines, and in some cases it has lead to outbreaks of vaccine preventable diseases such as the measles or pertussis... with the end result being hospitalizations, prolonged illness, and in a few select cases even death.

Therefore antivaxxers can continue to protest that no double-blind randomized and controlled studies on the efficacy of the flu vaccine have been performed, but it won't change anything and is merely a distraction.  As much as we might love to see such a study, it won't be happening anytime soon not only because of the ethical issues, but because anytime a study is performed and the treatment has such profound effects, the study will be interrupted.  It is simply inhumane to continue a study when a sample group shows such a significant benefit over the control group, and any long-term study of a vaccine is most certainly going to show this disparity thus we must look elsewhere for the necessary data.

Granted it isn't like we can't look at actual historical data to know if something works.... say for instance the fact that the CDC reported the incidence of invasive Hib disease dropped from 40-100 per 100,000 children down to 1.3 per 100,000 due to routine usage of the Hib vaccine from 1980 to 1990. Surely that is merely a coincidence.

Then again, Australia found the same thing... which results in this chart showing how the Hib vaccine resulted in over a 90% drop in reported cases in 12 years and actually eliminated all fatalities within 7 years.


It still must just be a coincidence right?  I mean we can't use this type of data because it isn't part of a double-blind randomized and controlled study... so it must be garbage.

Then again, there have never been double-blind randomized and controlled studies proving the efficacy of parachutes either, and there won't be anytime soon.  Does that mean we shouldn't trust the efficacy of parachutes?  Of course not, because we already know they save lives.  We already have more than enough evidence to know that parachutes are a great idea, and we know what the alternative is.  To suggest we need a double-blind study to determine whether parachutes work or not would be unethical (and obviously idiotic), but when you think about it, vaccines are no different.


So the next time an antivaxxer asks for a double-blind study aka: a "vax vs. unvaxxed" study showing the efficacy of vaccines, just ask them if they are willing to participate in a double-blind study for parachutes.  Sure that seems incredibly stupid, but so does the idea of passing on a vaccine because of scientific ignorance or fear.

Now if you need an example that is more in tune with vaccine, simply look no further than shoulder-mounted three point safety belts in automobiles.  We know the usage of such devices has resulted in many lives saved, and we know what the statistics are prior to their usage much in the way we know what the rates of disease were prior to vaccines being developed.  So should automobile manufacturers be required to perform double-blind studies on seat belts prior to installing them in vehicles?  Should they be required to report any findings of shoulder injury or broken arms due to the seat belts even though those same people may have died without the seat belt?

Our world isn't always so black and white, and sometimes the data is impossible to obtain via a perfectly controlled scientific study.  In some cases we need to look at the other sources of evidence such as infection rates or historical data.  It may not always be as clean and concise as a chart listing infection rates of X vs. Y, but unless you are willing to jump out of a plane without a parachute you really have no business complaining about a lack of double-blind studies.

Friday, November 16, 2012

Move the Goalposts... It's Time to Talk Aluminum

Spend more than five minutes on an anti-vaccination website and you will soon realize that most antivaxxers aren't exactly fans of aluminum.  No we aren't talking about aluminum cans or cookware, but rather we are talking about aluminum in a salt form which is commonly used in vaccines to act as an adjuvant.  In simple terms, the aluminum increases the effectiveness of a vaccine due to how it triggers a reaction within the immune system.

Aluminum has been used within vaccines for over 80 years, so you might ask yourself why are antivaxxers suddenly so focused upon aluminum when it isn't exactly a new ingredient?

Well to answer that, you first need to realize where we have been.  Antivaxxers have previously attempted to single out other ingredients such as thimerosal as they blamed it for various conditions up to and including autism in children.  They used scare tactics to associate thimerosal with mercury poisoning due to a misunderstanding of the differences between ethylmercury and methylmercury.

However, even prior to these cries of mercury poisoning from the antivaxxer community, the Food and Drug Administration (FDA) was already in the process of reviewing the use of thimerosal in vaccines.  Under the FDA Modernization Act (FDAMA) of 1997, the FDA carried out a comprehensive review of the use of thimerosal in vaccines.  The review found no evidence of harm from the use of thimerosal other than local hypersensitivity reactions near the injection site.

In the early 2000's, the Immunization Safety Review Committee of the Institute of Medicine (IOM) performed a review of all available research including studies in the United States, the United Kingdom, Sweden, and Denmark and they specifically focused upon the hypothesis that thimerosal was a contributing factor to childhood diseases such as autism.  The committee concluded that the available data and studies rejected the casual relationship between thimerosal (or vaccines containing thimerosal) and autism.

This is probably a good time to mention the fact that the IOM is part of the National Academy of Sciences and is a non-governmental institution. That may not seem particularly relevant, but since antivaxxers have a severe distrust for the federal government or any three letter agency (CDC, FDA, EPA et al), it should be clarified that the IOM is an independent organization and therefore would not share the same perceived bias(es) as a government agency.

Even though the IOM rejected the relationship between thimerosal and autism the FDA, as a preventative measure which had begun years earlier, was already in the process of removing thimerosal from vaccines.  As of 2001 thimerosal was removed from all childhood vaccines recommended for children six years of age or younger (keep in mind autism generally presents itself between ages two and four), and the only exception to this were some versions of the inactivated flu vaccine (although thimerosal-free versions are available).  In addition to this, all new non-influenza vaccines licensed since 1999 contain no thimerosal.

So what was the end result of removing thimerosal from childhood vaccines? Did we see a significant drop in the rates of autism? Nope. In fact, since 2001 the rates have actually gone up, and thus the theory that thimerosal was responsible for the "autism epidemic" was quite obviously no longer popular to rally behind. Children who had never received even trace amounts of thimerosal were still being diagnosed with autism and therefore antivaxxers realized they could no longer place blame upon thimerosal. It soon became obvious it was time to try something new.

Move the goalposts - we have another new theory!

When antivaxxers realized that pinning their hopes upon thimerosal might not exactly pan out, they shifted gears a bit and started focusing on one specific vaccine (the MMR vaccine) which they claimed was directly responsible for autism in children.  It was around this time that they started professing that Andrew Wakefield was a genius and seemed to have the secret to unlocking the root cause of autism due to a study he published in 1998 which attempted to link the MMR vaccine with autism.

Of course after Wakefield was discredited and stripped of his medical license, and after his "study" was retracted, and after he was found guilty of fraud and manipulation of data.... well he didn't exactly seem like the great savior afterall and he soon found himself the laughing stock of the scientific community.  It was around this time that many antivaxxers decided to back-peddle a bit and distance themselves from Wakefield (although in some extreme antivaxxer circles, Wakefield continues to be considered a favorite son).

So at that point the antivaxxers decided that instead of focusing on the MMR vaccine specifically, they should simply talk about vaccines or vaccine ingredients in more general terms because scaring people by talking about mercury poisoning or "toxicity" is generally more effective than trying to convince people that a discredited doctor was right all along.

You guessed it - time to pick up those goal posts and slide them back just a bit further!

A few years ago around the time many antivaxxers decided to stop talking about thimerosal or the MMR vaccine, they decided to start talking about other vaccine ingredients such as formaldehyde.  Why the focus on formaldehyde?  Well it surely had nothing to do with science, but rather it was about perception.  It seems most people associate formaldehyde with high school Biology class where a fetal pig or a frog was stored in it prior to dissection.  They recall the strong odor and the fact there were warning labels which stated severe over-exposure to the liquid could result in death.  They also associate formaldehyde with embalming fluid and dead bodies... so surely this isn't something that should be in a vaccine should it?

Well the truth is there is very, very little formaldehyde in vaccines, and it just so happens that we already have far greater quantities of formaldehyde in our bodies at any given point than we ever receive from any vaccine.  It turns out we have around about 2.5 ug of formaldehyde per ml of blood.
Per the Children's Hospital of Philadelphia's (CHOP) Vaccine Education Center: "Assuming an average weight of a 2-month-old of 5 kg and an average blood volume of 85 ml per kg, the total quantity of formaldehyde found in an infant's circulation would be about 1.1 mg, a value at least five-fold greater than that to which an infant would be exposed in vaccines".
In fact, we as humans actually NEED formaldehyde to survive since it is required for the synthesis of DNA and amino acids, thus suggesting the amount in vaccines would somehow be harmful was at best ignorant, and most likely simply dishonest.  Thus after antivaxxers realized the amount of formaldehyde found in vaccines was insignificant, they actually went so far as to suggest there is a difference between "natural" formaldehyde, and "synthetic" formaldehyde... once again showing that antivaxxers seem to ignore even the most basic tenets of chemistry.

The formaldehyde argument didn't seem to gain much traction however - most likely since anyone who has ever taken a basic chemistry course understands what formaldehyde really is - so the antivaxxers soon decided it was time for something new.

Get the shovel out... those goalposts need to be moved yet again!

This brings us to present day - when many antivaxxers have decided the one ingredient within vaccines which is REALLY, REALLY harmful (for reals this time), and the one ingredient that has the potential to cause the most damage is none other than aluminum.  Per the Centers for Disease Control (CDC), "[a]luminum salts, such as aluminum hydroxide, aluminum phosphate, and aluminum potassium sulfate have been used in vaccines for more than 70 years" so you might think the antivaxxers are a bit late to the game... but hey - better late that never right?

I suppose to the layman, telling them you are going to inject them with aluminum sounds about as appealing as telling them you are going to inject them with mercury.  Saying these things scares people... and isn't that the point?  We can't expect people to realize that the aluminum is the most common metal on the entire planet can we?  Can we expect them to know that there is a vast difference between a chemical compound containing aluminum and an actual piece of aluminum that may be used to form a soda can?

The truth is, aluminum is actually all around us, and even in us.  Aluminum is found in our water, it is found in our the soil, it is found in the air, it is commonly used in antacids, aspirin, and yes it is even found in our food including fresh fruits, vegetables, and meat.

So what is an antivaxxer to do when they soon realize that aluminum is all around us? What can they do when they find out the average human contains between 50 and 150 mg of aluminum at any given time?  What do they do when the find out the average daily intake of aluminum may range from 10-110 mg?   Well... they simply decide to focus on the amount of aluminum in vaccines rather than the amount of aluminum anywhere else in our body or our environment. Seems legit.

The problem is, vaccines really don't contain very much aluminum.  A typical vaccine contains no more 0.85 mg of aluminum per dose.  To put this in perspective, aluminum is also found in soy-based infant formula (0.46–0.93 mg/L) and milk-based infant formula (0.058–0.15 mg/L) which means an infant will consume more aluminum in a few days of drinking formula than it would receive from a typical vaccine.
Per CHOP, "During the first 6 months of life, infants could receive about 4 milligrams of aluminum from vaccines. That’s not very much: a milligram is one-thousandth of a gram and a gram is the weight of one-fifth of a teaspoon of water. During the same period, babies will also receive about 10 milligrams of aluminum in breast milk, about 40 milligrams in infant formula, or about 120 milligrams in soy-based formula.
Even more shocking, a common over the counter antacid has around 300-600 mg of aluminum hydroxide (approximately 104–208 mg of aluminum) per tablet, capsule, or 5 milliliter (mL) liquid dose! That means if you take a single tablet of a commonly available antacid, you are consuming as much as 245 times more aluminum than you would get out of a typical vaccine.

So why aren't antivaxxers out there protesting against antacids?  If you consider how much aluminum a typical adult human might consume in a 24 hour period as a result of some heartburn, it would seem to be the equivalent of hundreds and hundreds of vaccinations, yet antivaxxers fail to even mention it.  Why are these same antivaxxers not signing petitions to have soy-based infant formula removed from store shelves when it exposes infants to 30 times as much aluminum as vaccines within the child's first six months of life?  Could it be the antivaxxers are just slightly biased due to all of their previously failed attempts at pinning the root cause of autism on the vaccine industry?

The truth is, even if someone does ingest 2000 mg of aluminum in a single day, it will quickly leave their body via their feces and urine, which results in over half being flushed out of the body within 24 hours and over 70% of the aluminum being flushed out of the body within five days.  There have been some reports of long term complications surrounding high levels of aluminum exposure which I am certain many antivaxxers have latched on to, but unfortunately for them there have been long term complications from exposure to every element and chemical compound known to man.  As it turns out, the number one cause of drowning in humans is a result of too much exposure to H2O (commonly called "water"), yet I don't hear many people asking for the government to investigate Evian or Aquafina to see if they are killing people.  Go figure.

Sort of makes you wonder where the goalpost will move next doesn't it?

Monday, July 23, 2012

Facts, More Facts, and Persistent Facts

On an almost daily basis, I'm reminded of the John Adams quote "facts are stubborn things", and I am reminded of how accurate those words are.  Facts tend to get in the way of opinion, they shatter falsehoods, and they destroy dishonesty.  However, it seems often when facts are presented, those who find their opinions to be threatened merely ignore the facts rather than accept them.  This is often true with anti-vaxxers including Lowell Hubbs, because even after showing him evidence that disputes his statements, he refuses to accept reality.

Let me give an example.  Mr. Hubbs continues to make claims that the Amish are not vaccinated and that they don't get autism.  He has made these statements in the past, even though I showed him evidence which absolutely destroys that baseless claim including several different articles which served as sources.  Do you think Mr. Hubbs would drop the assertion that the Amish don't vaccinate?  Do you think he would back down from the claim that Amish children don't get autism? Do you think he would go back and modify his websites and blogs to remove any statements which make claims that the Amish don't vaccinate or that they don't get autism?  If your answer was no to any of the above questions, give yourself a gold star.

In fact, Mr. Hubbs continues to believe the Amish are autism-free, and he is still making claims about how they aren't vaccinated even though there is no legitimate evidence to support these claims.  Even if either of those two statements were true it still does not in any way suggest vaccines cause autism.  It is a classic misunderstanding of correlation and causation, and Mr. Hubbs is deliberately trying to blur the line between the two in order to support his worldview.

If someone actually has a desire to learn the truth about the Amish, there are more than enough sources that exist to prove that they do in fact vaccinate.  These include the articles mentioned above, news reports, and even studies. In fact, in one study it was found that 84% of Amish households with children reported that all of their children had received vaccinations and another 12% of Amish households with children reported that some of the children had received vaccinations. Only 4% of these households reported that none of the children received vaccinations.

That same study found that when it comes to older members of the Amish community who knew their own vaccination status, 90% reported that they had in fact received vaccinations as children. When broken out by age and looking at only respondents aged 45 years or less, this number swells to 96% which is actually higher than the general population in some cases. Does that sound like the Amish don't vaccinate?

As to the original author that made the claims about the Amish (Dan Olmsted), even he has had to backtrack and admit his reporting was "anecdotal" rather than scientific, and he seems to have backed down from his suggestions that a perceived lack of autism within the Amish community had a relation to vaccines. Of course he is still beating the drum trying to claim the Amish have a lower rate of autism (which very well could be true due to environmental and genetic factors) and he is still trying to confuse correlation and causation as all good anti-vaxxers do, but it does appear to some degree he is avoiding the "vaccines cause autism" nonsense primarily because he cannot support that hypothesis with any available data or research.

This is one of the primary issues I have with anti-vaccinationists. Even when presented with data that clearly shows their statements and opinions to be wrong, they simply ignore the data and continue to make the same false statements in the hopes they might be able to get away with it. It is one thing to form a hypothesis when you don't know the facts, but when the facts are in and when they seem to contradict your original opinion, it is nothing short of intellectual dishonesty to continue down the same path as if the facts don't matter.

Let's be clear - the Amish community isn't limited to one small group nor is it isolated to one area of the country. There are at least 25 states in the US with Amish populations, there are various subgroups and sects, so it stands to reason that what may be the case in one Amish community may not transcend across all. It would not be fair to make a blanket statement that all Amish communities vaccinate nor would it be fair to claim that none of the Amish are autistic, because the truth is there are both vaccinated and un-vaccinated Amish just as their are Amish children who have autism.

If anti-vaxxers really wish to be honest and if they are sincere in their desires to learn about the root causes of autism, they would be well advised to stop repeating fallacies and instead focus on what we really know instead of merely what we want to believe.

Monday, April 23, 2012

Is Obesity During Pregnancy a Risk Factor for Autism?

It is important to preface this information by stating that although this study is very interesting, this in no way proves autism is caused by obesity, or more specifically obesity during pregnancy.  There are a number of factors that most likely contribute to autism, and this is merely one such factor.

What this study did find was that women who were obese during pregnancy were about 67 percent more likely to have autistic children than women who were considered normal-weight during pregnancy.  That is a significant development, but one which needs confirmation via additional research.  If this holds true, then this is yet another piece of the puzzle which coupled with other research can lead us towards finding the true root cause(s) of autism and hopefully (eventually) to treatment programs and even a cure.

USA Today (AP): Autism may be linked to obesity during pregnancy

Full study can be found in the Journal Pediatrics:  Maternal Metabolic Conditions and Risk for Autism and Other Neurodevelopmental Disorders

The question remains - how can antivaxxers like Lowell Hubbs spin all of this new research to shift the blame back onto the vaccines they claim cause autism?  Can they just conveniently ignore these studies?  Can they claim obesity is caused by vaccines themselves?  Will they try to pretend the increased risk from obesity is merely a trigger and that the root cause is still vaccines?

It is anyones guess, but considering how often antivaxxers confuse correlation and causation, you might think they would be quick to recognize that as the obesity epidemic in our nation has ballooned (pardon the pun) so has the autism epidemic.  Of course I am not one to draw conclusions based upon random coincidences... but then again I'm not an antivaxxer.

Perhaps this is a good time to mention that Jenny McCarthy weighed in at 211lbs during her pregnancy with her son Evan (who she claims was autistic until she magically 'cured' him).  Considering McCarthy is 5'7" and around 125lbs, a health weight range during pregnancy would have resulted in her gaining between 28 and 40lbs.  Thus, in no uncertain terms, McCarthy was clinically obese during her pregnancy as she was carrying at least 46 extra pounds on her frame.

For the record I'm not suggesting that McCarthy's weight resulted in her son being autistic, primarily because I can't be certain her son actually is (or was) autistic in the first place.  However if her son is autistic, it seems her massive weight gain during her pregnancy was likely a significant risk factor, and as such will most likely go unmentioned by McCarthy or anyone else in the anti-vaccination camp.  Why you ask?  Because antivaxxers would never be willing to accept that their actions might contribute to their children being diagnosed with autism, and instead it is much easier to just blame vaccines or drug companies or pediatricians or hospitals.  It seems it isn't really about finding a root cause... it is about finding someone else to blame. 

Sadly, this seems to be the American way as everyone claims to be a victim and they are never to blame for something that might go wrong.  If something happens to a child, the parents look around for someone to blame.  If someone gets caught driving drunk, they blame the police or the judge.  If they are arrested for theft, they blame a substance abuse issue.  If they suffer from a medical condition or have issues controlling their rage, they look to a doctor or drug company to blame, but rarely do people actually look in a mirror and accept responsibility for their own lives.

Any way you spin it, this is not a good time to be an anti-vaccinationist, and 2012 is shaping up to be one of the worst years on record for Lowell Hubbs, Jenny McCarthy, and their antivaxxer brethren.