Screening 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.
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):
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.
Unfortunately, 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.
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.
I recently saw a 14 year old girl in my office with a 2 day history of severe abdominal cramps, bloody diarrhea, and fever. Her mother had similar symptoms as did several other members of her household and some family friends. After considerable discomfort, everyone recovered within a few days. The child’s stool culture grew a bacterium called Campylobacter.
Campylobacter is a nasty little pathogen which causes illness like that seen in my patient, but can also cause more severe disease. It is found commonly in both wild and domestic animals. But where did all these friends and family members get their campylobacter infections? Why, from their friendly farmer, of course!
My patient’s family and friends had taken a weekend pilgrimage to a family-run farm in Buck’s County, Pennsylvania. They saw farm animals and a working farm. And they all drank raw milk. Why raw milk? Because, as they were told and led to believe, raw milk is better. Better tasting and better for you.
In 1862, the french chemist Louis Pasteur discovered that heating wine to just below its boiling point could prevent spoilage. Now this process (known as pasteurization) is used to reduce the number of dangerous infectious organisms in many products, prolonging shelf life and preventing serious illness and death. But a growing trend toward more natural foods and eating habits has led to an interest in unpasteurized foods such as milk and cheese. In addition to superior taste, many claim that raw milk products provide health benefits not found in the adulterated versions. Claims made about the “good bacteria” (like Lactobacillus) conquering the “bad” bacteria (like Campylobacter, Salmonella, and E. coli) in raw milk are pure fantasy. Some even claim that the drinking of mass-produced, pasteurized milk has resulted in an increase in allergies, heart disease, cancer, and a variety of other diseases. Again, this lacks any scientific crediblity.
On May 9th I had the pleasure of lecturing to an audience of critical thinkers at the NYC Skeptics meeting. The topic of discussion was pseudoscience on the Internet – and I spent about 50 minutes talking about all the misleading health information and websites available to (and frequented by) patients. The common denominator for most of these well-intentioned but misguided efforts is a fundamental lack of understanding of the scientific method, and the myriad ways that humans can fool ourselves into perceiving a cause and effect relationship between unrelated phenomena.
But most importantly, we had the chance to touch upon a theme that has been troubling me greatly over the past couple of years: the rise in influence of those untrained in science on matters of medicine. I have been astonished by the ability of “thought leaders” like Jenny McCarthy to gain a broad platform of influence (i.e. Oprah Winfrey’s TV network) despite her obviously flawed beliefs about the pathophysiology of autism. Why is it so hard to find a medical voice of reason in mainstream media?
The answer is probably related to two issues: first, good science makes bad television, and second, physicians are going about PR and communications in the wrong way. We are taught to put emotions aside as we carefully weigh evidence to get to the bottom of things. But we are not taught to reinfuse the subject with emotion once we’ve come to an impartial consensus. Instead, we tend to bicker about statistical analyses, and alienate John Q. Public with what appears to him as academic minutiae and hair-splitting.
I’m not sure what we can or should offer in place of our “business as usual” behavior – but I’ve noticed that being right isn’t the same as being influential. I wonder how we can better advance the cause of science (for the sake of public health at a minimum) to an audience drawn more to passion than to substance?
I would really enjoy your input, dear readers of Science Based Medicine, because I’m at a loss as to what we should do next to reach people in our current culture, and with new communications platforms. What would you recommend?
Perhaps you have discovered for yourself that I am always the last to write a post on a ‘hot’ topic. I am definitely the slowest writer (and thinker?) on this blog, starting each post at least a week before it is up. So the faster writers weigh in first and I am left with clean up.
As I finish writing on Thursday, there have been 892 cases of H1N1 aka Swine flu and 2 deaths in the US. Looks like the world has avoided a disastrous pandemic like the 1919 flu that killed off 2 to 5% of the world. For now. Maybe. I hope.
However, the flood of nonsense about the flu far exceeds the infection rates from H1N1. This entry will be the limited by necessity. The quantity of quackery (9) far exceeds my ability to type. I thought that influenza virus replicated and spread fast. It pales next to the flu woo.
My inaugural post was about vaccines, and I promised that I wouldn’t write exclusively on this topic. But something rotten is brewing in the state of Georgia and this story is just too important to ignore.
The first successful challenge to the National Childhood Vaccine Injury Compensation Act (NCVICA) has taken place in Georgia, and we all should be just a little bit worried. In Ferrari v. American Home Products Corp., the plaintiffs, Marcello and Carolyn Ferrari of Atlanta, have sued American Home Products Corp. (otherwise known as Wyeth) and the co-defendant GlaxoSmithKline, claiming that the vaccine preservative thimerosal led to their son’s autism. The consequences of this ruling could effect the health of the entire nation. To understand why, we need to delve a bit into what the NCVICA is exactly, and why it was created in the first place.
In 1918 the Spanish Flu (named after the country of origin of the first reported case) swept the globe, killing 20-40 million people – more than the First World War (which killed 15 million) which was just ending. When an epidemic spreads to multiple regions, especially multiple countries or continents, it becomes a pandemic. Flu pandemics happen 2-3 times each century.
This is probably partly why there has been so much news attention, even some mild hysteria, surrounding recent outbreaks of swine flu, beginning in Mexico. It is hard to say how many cases and how many deaths there have been so far, because information from Mexico is spotty. Specifically it is difficult to say if people who have died with flu-like symptoms really had the swine flu or something else.
Estimates are that more than 800 people have contracted the swine flu in Mexico with 29 confirmed deaths, although none in the last week. The Centers for Disease Control (CDC) reports as of May 5th that there have been 403 confirmed cases in the United States, with the first death just reported. World-wide there have been 1,490 cases in 21 countries (according to the World Health Organization- WHO).
Some Background on Influenza
The influenza or flu virus is an RNA virus that comes in three genera – A, B, and C. Influenza A is the most common type. It can infect mammals and birds, with aquatic birds being its natural endemic host. Each year there is a seasonal epidemic of Influenza A, infecting millions of people world-wide and killing 100-200,000 – mostly the very old, the very young, and the sick.