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An Influenza Primer

The President’s Council of Advisors on Science and Technology recently submitted its report to the president in which they stated that this influenza season might kill 30-90,000 people in the US.  This forecast of the upcoming season caught the media’s attention and appears to have stoked the public interest in influenza.  We have had many requests for more information about influenza here at SBM, and so in this post I am going to discuss the basics of influenza and try to put the current pandemic and upcoming season in perspective.

I find it is best to start at the beginning.

What Is Influenza?

Within the public sphere, “The flu” has become shorthand for “I feel like crap.”  I suspect that this is part of the reason why some people think the influenza vaccine doesn’t work.  Medically speaking, however, influenza is a very specific family of viruses that cause a reasonably narrow set of problems for humans.

The influenza season in the Northern hemisphere usually runs from October through May, with a peak mid-February.  Every season in the US between 5-20% of the US population is infected by influenza, and while the majority of people recover well from an influenza infection, not everyone will.  Annually 200,000 people are hospitalized, and on average 36,000 will die either from influenza or its complications.

The classic influenza infection incubates for 1-4 days after exposure.  Its onset is rapid, with most people experiencing high fever, headache, muscle aches, dry cough, sore throat, and nasal congestion.  Gastro-intestinal symptoms like nausea, vomiting, and diarrhea are less common.  Symptoms last from several days to almost two weeks, and a person is contagious from one day before symptoms begin to more than a week after symptom onset.

There are many strains of influenza. The current seasonal influenza is made up of three different influenza subtypes: A(H3N2), A(H1N1), and B.  Don’t confuse the seasonal A(H1N1) strain with the current pandemic 2009 A(H1N1); they are distinct.  I will refer to them as A(H1N1) for the seasonal strain, and 2009 (H1N1) for the pandemic “swine flu” strain.  Influenza B is less common, less virulent, has a slower mutation rate, and is thus a lesser risk; the rest of this discussion is focused on Influenza A. (more…)

Posted in: Public Health, Science and Medicine, Vaccines

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The perils and pitfalls of doing a “vaccinated versus unvaccinated” study

The anti-vaccine movement is nothing if not plastic. It “evolves” very rapidly in response to selective pressures applied to it in the form of science refuting its key beliefs. For instance, when multiple studies looking at the MMR vaccine and autism failed to confirm the myth that the MMR causes autism or “autistic enterocolitis,” most recently late last year, it was not a problem to the anti-vaccine movement. Neither was it a major problem to the movement when multiple studies similarly failed to find a link between mercury in the preservative thimerosal that used to be in most childhood vaccines and is no more (except the flu vaccine) and autism. No problem! Andrew Wakefield is alleged, based on strong evidence, to have falsified his data alleging a link between the MMR vaccine and “autistic enterocolitis”? Fuggedabouddit! The anti-vaccine movement simply pivoted neatly, de-emphasized points that the evidence was so clearly against that even they couldn’t spin it to a positive anymore, and found new bogeymen. These days, it’s the “toxins” (such as formaldehyde and the latest antivax bogeyman, squalene), and “too many too soon” (a gambit given seeming respectability by Dr. Bob Sears and Dr. Jay Gordon, apologists for and supplicants to the anti-vaccine movement both.

However, there is one trait of the anti-vaccine movement that, however its camouflaging plumage may evolve, never, ever changes. It is as immutable as believers say that God is. That trait is that, whatever other claims, the anti-vaccine movement makes, at its core it is always about the vaccines. Always. No matter how often science fails to find a link between vaccines and autism or vaccines and whatever other horreur du jour the anti-vaccine movement tries to pin on vaccines, no matter how many studies do not support the viewpoint that vaccines cause autism, no matter how much the anti-vaccine movement tries to deny and obfuscate by saying that it is not “anti-vaccine” but rather “pro-safe vaccine,” at its core the anti-vaccine movement is about fear and loathing of vaccines. Always. When inconvenient science doesn’t support their views, anti-vaccine activists either ignore the science, distort the science, or launch ad hominems against the people doing the science or citing the science. And, as I said before, the claims of the anti-vaccine movement evolve. Never again will the anti-vaccine movement make the horrific mistake of yoking itself to a hypothesis that is as easily testable as the hypothesis that mercury in vaccines causes autism. The claim that mercury in vaccines causes autism predicted that, if thimerosal were removed from vaccines or reduced to pre-”epidemic levels” of the early 1990s, then autism rates should plummet. Thimerosal was removed from nearly all childhood vaccines (the sole exception being some flu vaccines), reducing infant mercury exposure from vaccines to levels not seen since the 1980s; yet autism rates continue to rise. This is about as resounding a refutation of the hypothesis that mercury in vaccines is a major cause or contributor to autism that even the anti-vaccine movement has backed away from the pure claim, which has now evolved to unnamed “environmental toxins,” either in concert with mercury or with other nasty things, as being the Real One True Cause of Autism.

It’s evolution in action. These new claims are much “fitter” because they are much harder to falsify through scientific research, epidemiology, and clinical trials.
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Posted in: Clinical Trials, Medical Ethics, Public Health, Science and Medicine, Vaccines

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A Defense of Childhood Influenza Vaccination and Squalene-Containing Adjuvants; Joseph Mercola’s “Dirty Little Secret”

Fall is around the corner, and with it comes the influenza season.  Each year an average of 200,000 people in the US are hospitalized with influenza, and 36,000 die.1,2 With the addition of the novel H1N1 strain (swine flu), this season promises to be more interesting, and even less predictable, than most.  There can be no doubt, however, that this one set of viruses will exact a heavy toll for thousands of families this season.

Too often in medicine we find ourselves confronted with problems we cannot fix.  Some traumas are too severe, some infections have too much of a head start.  Some diseases are poorly understood, while others have no known treatment.  One of the darker adages of medicine still holds true: In spite of all our advances, the world mortality rate seems to be holding quite steady at 100%.

Thankfully, influenza is not a disease against which we are helpless. We have ways to limit its spread, and medicines with a modest effect in assuaging symptoms and shortening the length of illness.  Most importantly, we have vaccines that can safely prevent the disease altogether.

There are myriad misconceptions and fears surrounding the influenza and its vaccines, most are not new and have been addressed elsewhere, including the concern that the influenza vaccines cause the flu (they don’t), that the thimerosal they contain causes autism (it doesn’t), and that it can trigger Guillan Barre Syndrome (it can3, at a rate of 1/1,000,000, similar to the background rate of Guillan Barre in the population4).  The confusion has been compounded by the emergence of the novel H1N1 pandemic.  With so much at stake, it is exceedingly important to have clear, accurate information available to physicians and the public alike. (more…)

Posted in: Public Health, Vaccines

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Cashing In On Fear: The Danger of Dr. Sears

I generally know what’s coming next when a parent asks about altering their child’s vaccine schedule: “I was reading Dr. Sears….”

Dr. Sears is a genius. No, not in an Albert Einstein or Pablo Picasso kind of way. He’s more of an Oprah or a Madonna kind of genius. He’s a genius because he has written a book that capitalizes on the vaccine-fearing, anti-establishment mood of the zeitgeist. The book tells parents what they desperately want to hear, and that has made it an overnight success.

Dr. Robert Sears is perhaps one of the best-known pediatricians in the country. The youngest son of Dr. Bill Sears, the prolific parent book writer and creator of AskDrSears.com, Dr. Bob has become the bane of many a pediatrician’s existence. He has contributed to his family dynasty by co-authoring several books, adding content to the family website, and making myriad TV appearances to offer his sage advice. But Dr. Bob is best known for his best-selling The Vaccine Book: Making the Right Decision for your Child. This book, or at least notes from it, now accompanies many confused and concerned parents to the pediatrician’s office. Parents who have been misled by the onslaught of vaccine misinformation and fear-mongering feel comforted and supported by the advice of Dr. Sears, who assures parents that there is a safer, more sensible way to vaccinate. He wants parents to make their own “informed” decisions about whether or how to proceed with vaccinating their children, making sure to let them know that if they do choose to vaccinate, he knows the safest way to do it. And for $13.99 (paperback), he’ll share it with them.

In the final chapter of his book (entitled “What should you do now?”), after reinforcing the common vaccine myths of the day, Dr. Sears presents his readers with “Dr. Bob’s Alternative Vaccine Schedule.” He places this side-by-side with the schedule recommended by the American Academy of Pediatrics and the CDC’s Advisory Committee on Immunization Practices. He then explains why his schedule is a safer choice for parents who chose to vaccinate their children. Without a doubt, the alternative vaccine schedule is among the more damaging aspects of this book. It’s the part that gets brought along to the pediatrician’s office and presented as the the plan going forward for many parents today. But the book is also dangerous in the way in which it validates the pervasive myths that are currently scaring parents into making ill-informed decisions for their children. Dr. Sears discusses these now common parental concerns, but instead of countering them with sound science, he lets them stand on their own as valid. He points out that most doctors are ill-equipped to discuss vaccines with parents, being poorly trained in the science of vaccine risks and benefits. He then claims to be a newly self-taught vaccine expert, a laughable conceit given the degree to which he misunderstands the science he purports to have read, and in the way he downplays the true dangers of the vaccine-preventable diseases he discusses in his book. He then provides parents with what he views as rational alternatives to the recommended vaccination schedule, a schedule designed by the country’s true authorities on vaccinology, childhood infectious disease, and epidemiology.

So what does Dr. Sears have to say, exactly, about the risks of vaccines, and just how out of touch is he with medical science and epidemiology? (more…)

Posted in: Book & movie reviews, Public Health, Science and Medicine, Vaccines

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Are one in three breast cancers really overdiagnosed and overtreated?

ResearchBlogging.orgScreening for disease is a real pain. I was reminded of this by the publication of a study in BMJ the very day of the Science-Based Medicine Conference a week and a half ago. Unfortunately, between The Amaz!ng Meeting and other activities, I was too busy to give this study the attention it deserved last Monday. Given the media coverage of the study, which in essence tried to paint mammography screening for breast cancer as being either useless or doing more harm than good, I thought it was imperative for me still to write about it. Better late than never, and I was further prodded by an article that was published late last week in the New York Times about screening for cancer.

If there’s one aspect of medicine that causes more confusion among the public and even among physicians, I’d be hard-pressed to come up with one more contentious than screening for disease, be it cancer, heart disease, or whatever. The reason is that any screening test is by definition looking for disease in an asymptomatic population, which is very different from looking for a cause of a patient’s symptoms. In the latter case, the patient is already being troubled by something that is bothering him. There may or may not be a cause in the form of a disease or syndrome that is responsible for the symptoms, but the very existence of the symptoms clues the physician in that there may be something going on that requires treatment. The doctor can then narrow down range of possibilities for what may be the cause of the patient’s symptoms by taking a careful history and physical examination (which will by themselves most often lead to the diagnosis). Diagnostic tests, be they blood tests, X-rays, or other tests, then tend to be more confirmatory of the suspected diagnosis than the main evidence supporting a diagnosis.
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Posted in: Cancer, Clinical Trials, Diagnostic tests & procedures, Public Health, Science and Medicine, Science and the Media

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Counterfeit Drugs: A Growing Global Health Crisis

A resistant strain of bacteria –created by partially effective counterfeit antibiotics – doesn’t need a VISA and passport to get to the U.S.

-    Paul Orhii, National Agency for Food and Drug Administration and Control, Nigeria

I attended a conference in DC yesterday called, “The Global Impact of Fake Medicine.” Although I had initially wondered if homeopathy and the supplement industry would be the subjects of discussion, I quickly realized that there was another world of medical fraud that I hadn’t previously considered: counterfeit pharmaceuticals.

Just as designer goods have low-cost knock-offs, so too do pharmaceuticals and medical devices. Unfortunately, counterfeit medical products are a higher risk proposition – perhaps causing the death of hundreds of thousands of people worldwide each year.

It is difficult to quantify the international morbidity and mortality toll of counterfeit drugs – there have been no comprehensive global studies to determine the prevalence and collateral damage of the problem.  But I found these data points of interest (they were in the slide decks presented at the conference):
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Posted in: Pharmaceuticals, Politics and Regulation, Public Health

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Herd Immunity

Some infections can be eradicated from the face of the planet. Smallpox is the one example of disease eradication to date. Smallpox still exists in US and Russian labs, but there has been no wild cases since 1977.  It is, like the Dorothy, history.

Why were we able to eradicate smallpox?  Three reasons:

1) There is only one form of smallpox. Unlike influenza that changes from year to year.  So only one vaccine needed.
2) By what appears to be a once in a universe miracle, every county cooperated with  the WHO (much like we all cooperate with the IRS) so the entire planet received the vaccine. Once enough people were vaccinated, the disease was unable to perpetuate itself and spread and so died out.
3) Unlike bacteria, there are no asymptomatic smallpox carrier states.  Eradicable viruses usually cause symptomatic disease and do not result in asymptomatic, infectious carrier states that serve as a reservoir for infecting others.  HIV and Herpes cause chronic asymptomatic infections and will probably never be eradicated.

There are other diseases that are theoretically eradicable, like measles and polio. They have one antigenic type, have no carrier state and, if the entire world could be vaccinated, the disease would cease to exist in the wild.  I am sure there would be biologic weapons labs that would always carry a vial or 2 of every infection. Just to be safe.
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Posted in: Public Health, Science and Medicine, Vaccines

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The Oprah-fication of medicine

OprahUnfortunately, a frequent topic on SBM has been the anti-vaccine movement, personified these days by celebrity spokesmodel for Generation Rescue Jenny McCarthy and her dimmer than dim boyfriend comedian and actor Jim Carrey. Unfortunately, it is a topic that is unlikely to go away. We’ve all speculated why the anti-scientific emotion-based notion that vaccines somehow must cause autism persists in spite of mountains of evidence to the contrary, but I think the question goes much deeper than that because it’s not just about vaccines. The anti-vaccine movement is but one of the most visible components of a much deeper problem in our public discourse, a problem that values feelings and personal experience over evidence, compelling stories and anecdotes over science.

I’m referring to the Oprah-fication of medicine in America.
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Posted in: Public Health, Science and Medicine, Science and the Media, Vaccines

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Chemical castration for autism: After three years, the mainstream media finally notices

We’ve written a lot about anti-vaccine zealotry on this blog, as Steve and I take a particular interest in this particular form of dangerous pseudoscience for a number of reasons. One reason, of course, is that the activities of antivaccine groups like Generation Rescue and its spokesmodel since 2007 (Jenny McCarthy, a frequent topic on this blog) have started to frighten parents about vaccines enough that vaccination rates are falling well below that required for herd immunity in some parts of the country. Indeed, McCarthy, at the behest of her handlers in Generation Rescue, serves up a regular “toxic” brew of misinformation and nonsense about vaccines, most recently in a video that was the subject of a post by Val Jones about her unbelievably pseudoscience-laden blather. Truly, it has to be seen to be believed. Meanwhile, Generation Rescue has sent McCarthy on a media propaganda tour for her latest antivaccine pro-quackery book and set up a misinformation-laden propaganda site called Fourteen Studies (blogged about by Steve Novella, Mark Crislip, and, of course, yours truly) in which they attack well-designed studies that have failed to confirm their pet idea that somehow, some way, vaccines must be the cause of autism. And, when their pseudoscience is criticized, the antivaccine movement has a tendency to launch vicious ad hominem attacks, as they recently did against Steve Novella and have done multiple times in the past against me.

However, there is one other consequence of the antivaccine movement, however, and it is at least as important as the public health implications of the potential dimunition of herd immunity caused by the fear mongering of groups like Generation Rescue. That consequence is the cottage industry of “biomedical” treatments to which desperate parents subject their children. Gluten-free diets, chelation therapy (which has caused deaths), hyperbaric oxygen chambers (a recent story described a child getting severely burned when one of these caught fire), autistic children have been subjected to it all. But of all the biomedical woo to which autistic children have been subjected, one form of woo stands out as being particularly heinous. Indeed, I agree with our fearless leader Steve in characterizing it as an “atrocity.”

I’m referring to Mark and David Geier’s favored “treatment” for autistic children, namely a drug called Lupron.
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Posted in: Clinical Trials, Health Fraud, Medical Ethics, Neuroscience/Mental Health, Politics and Regulation, Public Health, Science and the Media, Vaccines

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