Public Health

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In which Dr. Gorski once again finds himself a target of the “pharma shill” gambit

EDITOR’S NOTICE: NOTE THE DISCLAIMER. Also note that there is a followup to this post entitled The price of opposing medical pseudoscience that is highly recommended after you read this post.

The “pharma shill gambit”: The quack’s favorite flavor of ad hominem argument

One of the very favorite and most commonly used tactics to attack criticism in the armamentarium of pseudoscientists, cranks, and quacks (not to mention politicians) is the ad hominem fallacy. In this fallacy, rather than addressing the actual evidence and science that demonstrate their favorite brand of woo to be nothing more than fairy dust, the idea is to preemptively attack and discredit the person. The ad hominem is not just insults or concluding that someone is ignorant because, well, they say ignorant things and make stupid arguments (in which case calling someone stupid or ignorant might just be drawing a valid, albeit impolitic, conclusion from observations of that person’s behavior), but rather arguing or insinuating that you shouldn’t accept someone’s arguments not because their arguments are weak but because they have this personal characteristic or that or belong to this group or that. Truly, the ad hominem is right up there with demanding public “debates” with skeptics as a favored defense strategy of cranks of all stripes.

Among the very favorite flavors of ad hominem attack used by quacks, cranks, and pseudoscientists is the fallacy of poisoning the well. This particular fallacy alludes to the medieval European myth that the Black Plague was caused by Jews poisoning town wells. Not surprisingly, this myth was used as a justification for pogroms and the persecution of the Jews. The idea is to poison how others view your opponent by preemptively attacking them. Well do I know this fallacy, having been at the receiving end of it many times! Basically, it involves invoking something bad or biased about a person’s situation or personality and then using a phrase something like, “Of course he (or she) would say that” to dismiss a person’s arguments, the implication being that the person receives such benefits from holding the position being attacked or has such a personality that he couldn’t argue otherwise regardless of the evidence. In my admittedly anecdotal experience, far and away the most common use of the ad hominem from quacks and pseudoscientists is what I once described as “the pharma shill gambit.” The idea behind this gambit when it comes to attacking those of us who promote science-based medicine is to tar one’s opponent as being a “shill” for big pharma or claiming that we have a conflict of interest so blatant that “of course we would say that.” In most cases, the bogey man is big pharma, in whose pockets we SBM bloggers are supposed to be safely (and profitably) ensconced, blogging away in our underwear for big bucks and, following the orders of our supposed paymasters, attacking anything that has even a whiff of being “alternative” or that “questions” the safety and/or efficacy of vaccines.

While I realize that there is such a thing as an “astroturf” campaign, in the vast majority of cases, the pharma shill gambit is nothing more than the variant of the ad hominem fallacy known as poisoning the well. I also realize that conflicts of interest (COIs) matter, particularly undisclosed COIs. Indeed, I wrote a rather lengthy post (I know, I know, do I write any other length of post?) about 8 months ago laying out my views regarding COIs in science-based medicine. The short version is that we all have COIs of some sort or another, be they financial, belief-based, or emotional, and more disclosure is usually better, to let the reader decide for himself. As far as COIs related to big pharma or finances, I think Mark Crislip put it quite well in his most recent Quackcast when he said that if a study is funded by big pharma, he decreases the strength of the evidence in his mind by a set amount. However, evidence is evidence, and, although it is reasonable to increase one’s level of skepticism if there is a major COI involving the authors, be it big pharma or otherwise, it is not reasonable to use that COI as the sole reason for rejecting its findings out of hand. That’s just an intellectually lazy excuse to dismiss the study, nothing more. Indeed, one prominent difference between a scientist and a pseudoscientist or quack is that in general scientists understand this and struggle to assign the correct degree of skepticism due to a COI when analyzing scientific studies, while quacks and pseudoscientists do not. It’s far easier for them just to put their fingers in their ears and scream “Conflict of interest! Conflict of interest!” and then use that to dismiss completely their opponent’s argument. It’s simple, neat, and it doesn’t require all that nasty thinking and weighing of evidence..
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Posted in: Medical Ethics, Neuroscience/Mental Health, Public Health, Vaccines

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WHO, H1N1, and Conflicts of Interest

On June 11, 2009 Dr Margaret Chan, the director general of the World Health Organization (WHO) declared that the H1N1 flu that was then spreading around the world was an official pandemic. This triggered a series of built-in responses in many countries, including stockpiling anti-viral medications and preparing for a mass H1N1 vaccination program. At the time the flu was still in its “first wave” and the fear was that subsequent waves, as the virus swept around the world, would become more virulent and/or contagious – similar to what happened in the 1918 pandemic.

This did not happen. At least our worst fears were not realized. The H1N1 pandemic, while serious, simmered through the winter of 2009-2010, producing a less than average flu season, although with some worrisome difference.

The Centers for Disease Control (CDC) estimates:

  • CDC estimates that between 43 million and 89 million cases of 2009 H1N1 occurred between April 2009 and April 10, 2010. The mid-level in this range is about 61 million people infected with 2009 H1N1.
  • CDC estimates that between about 195,000 and 403,000 H1N1-related hospitalizations occurred between April 2009 and April 10, 2010. The mid-level in this range is about 274,000 2009 H1N1-related hospitalizations.
  • CDC estimates that between about 8,870 and 18,300 2009 H1N1-related deaths occurred between April 2009 and April 10, 2010. The mid-level in this range is about 12,470 2009 H1N1-related deaths.

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Posted in: Public Health

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Nine differences between “us and them,” nine straw men burning

I’ll start this post by admitting right up front: I blatantly stole the idea for the title of this post from Mark Crislip’s most excellently infamous post Nine questions, nine answers. Why? Because I really liked that post and felt like it. Also, there seems to be something about the number nine among anti-vaccine zealots: Nine “questions.” Nine circles of hell.

Nine straw men.

I’m referring to an amazing post that appeared on the anti-vaccine crank blog Age of Autism over the weekend by contributing editor Julie Obradovic entitled The Difference Between You and Me. In this post, Julie describes not one difference, but nine differences, that she perceives between herself (and, apparently, by generalization other parents who have become believers in the myth that vaccines cause autism) and people like SBM contributors and (I hope) the vast majority of our readers, who support science-based medicine, understanding that correlation does not necessarily equal causation and that, most importantly, science not only does not support the belief that vaccines cause autism but provides us with copious evidence that there almost certainly no link between the two. Actually, there are more than nine differences, as Ms. Obradovic packs multiple apparently related differences around each of her nine “differences” and then complains that Alison Singer and, apparently by generalization the rest of us who support SBM and oppose the anti-vaccine movement, misrepresent the reasons why she and her merry band of anti-vaccine activists reject the science that has failed spectacularly to validate their deeply held belief that vaccines cause autism and all sorts of other health consequences. Her post ends up being a collection of straw men constructed to Burning Man size, each of which she then applies a flamethrower of burning nonsense to with self-righteous gusto.
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Posted in: Public Health, Science and the Media, Vaccines

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Is Organic Food More Healthful?

In 1952 Martin Gardner, who just passed away this week at the age of 95, wrote about organic farming in his book Fads and Fallacies in the Name of Science. He characterized it as a food fad without scientific justification. Now, 58 years later, the science has not changed much at all.

A recent review of the literature of the last 50 years shows that there is no evidence for health benefits from eating an organic diet. The only exception to this was evidence for a lower risk of eczema in children eating organic dairy products. But with so many potential correlations to look for, this can just be noise in the data.

Another important conclusion of this systematic review is the paucity of good research into organic food – they identified only 12 relevant trials. So while there is a lack of evidence for health benefits from eating an organic diet, we do not have enough high-quality studies to say this question has been definitively answered. It is surprising, given the fact that organic food was controversial in the 1950s, that so little good research has been done over the last half-century.

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Posted in: Nutrition, Public Health

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Epiphany

The Institute of Medicine report is a frequent ‘rebuttal’ to science based/real medicine. The argument is usually phrased something to the effect that since medicine can be dangerous, SCAM’s are legitimate. Of course, one does not follow the other. It is the equivalent of saying since you are old, bald and pudgy, I am young, have a full head of hair, and are thin. If every doctor and hospital were to vanish tomorrow like an episode of the Outer Limits, SCAM’s would be just a ineffective.

Despite the flawed logic of the comparison, I have always had an affinity for the estimates that 44,000 to 98,000 were (note the deliberate use of the past tense) killed each year in hospitals. There may be methodological flaws in the estimate but the ballpark figure is probably correct.

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Posted in: Public Health, Science and Medicine

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New Data on Cell Phones and Cancer

This is a science and medicine story we have been following for a while – out of personal and scientific interest, and the need to correct confused or misleading new reporting on the topic. Are cell phones linked to an increased risk of brain cancer or other tumors? New data is reassuring.

David Gorski and I have both written on this topic. To give a quick summary, there is no convincing data to link cell phone use and brain cancer. Epidemiological studies have not found an increase in the incidence of brain cancer following the widespread adoption of cell phones in the mid 1990s – as one would expect if there were a causal relationship. Further, large scale studies have not found any consistent correlation between cell phone use and brain cancer.

It is clear from the literature that there is no measurable increased risk from short term cell phone use – less than 10 years. There is no evidence to conclude that there is a risk from long term use (> 10 years) but we do not yet have sufficient long-term data to rule out a small risk. Further, the data is somewhat ambiguous when it comes to children – still no convincing evidence of a link, but we cannot confidently rule out a link.

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Posted in: Cancer, Public Health

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The 2008-2009 Report of the President’s Cancer Panel: Mostly good, some bad, and a little ugly

Mark Crislip is always a hard act to follow, particularly when he’s firing on all cylinders, as he was last Friday. Although I can sometimes match him (and, on rare occasions, even surpass him) for amusing snark, this time around I’m going to remain mostly serious because that’s what the subject matter requires. I’ve said it before and I’ll say it again: I’m a bit of an odd bird in the world of cancer in that I’m both a surgeon and I run a lab. Sadly, there just aren’t very many surgeons doing basic and translational research these days, thanks to declining NIH funding, increasing clinical burden necessitated by declining reimbursements, and the increasing complexity of laboratory-based research. That’s not to say that there aren’t some surgeons out there doing excellent laboratory research, but sometimes I feel as though I’m part of an endangered species, particularly years like this when grants are running out and I need to renew my funding or secure new funding, the consequence of failure being the dissolution of my laboratory. It’s a tough world out there in biomedical research.

As tough as biomedical research is in cancer, to my mind far tougher is research trying to tease out the relationship between environmental exposures and cancer risk. If you want complicated, that’s complicated. For one thing, obtaining epidemiological data is incredibly labor- and cost-intensive, and rarely are the data clear cut. There’s always ambiguity, not to mention numerous confounding factors that conspire to exaggerate on the one hand or hide on the other hand correlations between environmental exposures and cancer. As a result, studies are often conflicting, and making sense of the morass of often contradictory studies can tax even the most skillful scientists and epidemiologists. Communicating the science and epidemiology linking environment and cancer to the public is even harder. What the lay person often sees is that one day a study is in the news telling him that X causes cancer and then a month later another study says that X doesn’t cause cancer. Is it any wonder that people are often confused over what is and is not dangerous? Add to this a distinct inability on the part of most people, even highly educated people, to weigh small risks against one another (an inability that has led to phenomena such as the anti-vaccine movement), and the task of trying to decide what is dangerous, what is not, how policy is formulated based on this science, and how to communicate the science and the policy derived from it to the public is truly Herculean.
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Posted in: Cancer, Politics and Regulation, Public Health

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Outbreaks

There have been, in the last 20 years, natural, or perhaps unnatural, experiments that have helped shed light on the efficacy of vaccines.  Many societies, for reason of political unrest, religion, or a lack of understanding of science and medicine have seen the rates of vaccination decline and, with that decline, an increase in the cases of vaccine-preventable diseases.

Infectious disease spread in populations is not simple.  Hygiene, nutrition, access to health care, and education all play a role in the spread of communicable diseases.  Vaccines have been critical in driving the rates of vaccine preventable illnesses to almost zero, but they are not the only intervention in our armamentarium. (more…)

Posted in: Public Health, Vaccines

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A Welcome Upgrade to a Childhood Vaccine – PCV 13

Children aren’t supposed to die.  That so many of us accept this statement without a blink is remarkable and wonderful, but it is also a very recent development in human history.  Modern sanitation, adequate nutrition, and vaccination have largely banished most of the leading killers of children to the history books.  Just look at the current leading causes of childhood death in developing countries to see how far these relatively simple interventions have taken us.

As we have systematically removed the leading infectious killers of children from prominence, other organisms have naturally risen to the top of the list.  This has lead some to the fatalistic (and mistaken) conclusion that we are simply opening up niches to be inevitably filled by other virulent organisms.  This assumes that there is some mandated quota of say, meningitis, that children must suffer every year, and if one organism doesn’t meet this quota then another will fill it.  Were this the case, after vaccination we’d expect to see a shift in the causes of meningitis, but at best a transient drop in the total number of cases per year as other bugs step in to pick up the slack of their fallen, virulent, meningitis-inducing brethren.  Such is not the case.

Though new organisms are now the leading causes of invasive bacterial infections in children, and we have indeed seen some increases in non-vaccine targeted strains, as I’ll discuss below, the total number of such infections has dropped precipitously.  It’s fair to say that the vaccination program has done a remarkable job improving a child’s chance of surviving to adulthood in good health.  However, no one in their right mind would argue that the current state of affairs, as good as it is, is good enough, and so we have shifted our sights to the current leading cause of invasive bacterial infections in children, Streptococcus pneumoniae (S. pneumo, or pneumococcus). (more…)

Posted in: Public Health, Science and Medicine, Vaccines

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Changing Climate, Changing Infections

I will state my bias up front.  I am convinced by the preponderance of data in favor of man made global warming.  At the most simplistic level, I can’t see how converting humongous tons of fossil fuel into C02 and dumping it into the the atmosphere cannot have effects on the climate.  To my mind its like determining vaccine efficacy or evolution.  Plausible mechanism(s), good basic science, multiple studies using different lines of evidence that all come to the same conclusion.  There are lots of fine points and nuances to be worked out, but the basic truth is reasonable and well defined. Infectious diseases lend some validation to the concept that world is warming, since with global warming will come a variety of infectious diseases.
It is one big IF THEN statement.  IF global warming, THEN infections.  Of course the if the IF is not true, then the THEN doesn’t follow.
There is the weather, which the Action Channel News never seems to get right, and I will spare you the Mark Twain quote even though I think he is our best writer ever,  and there is the climate, the summation of weather over time.
Interestingly, infections have probably altered climate for short periods of times.  Through history humans burned trees releasing C02, chopped down forests for agriculture and raised animals, releasing methane.  As humans populations increased, both C02 from burning and methane from animals increased as well.  Every now and then large numbers of people have died off.  It happen when Columbus et. al. brought infections to the New World and when plague came to the Old.  People died.  Maybe 90% in the Americas (estimates vary widely) and 2/3’s of Europe died.  As a result, burning and agriculture decreased, decreasing emissions and forests grew back, sequestering C02.  And temperature rise slowed or decreased (http://stephenschneider.stanford.edu/Publications/PDF_Papers/Ruddiman2003.pdf).
“Abrupt reversals of the slow CO2 rise caused by deforestation correlate with bubonic plague and other pandemics near 200-600, 1300-1400 and 1500-1700 A.D. Historical records show that high mortality rates caused by plague led to massive abandonment of farms. Forest re-growth on the untended farms pulled CO2 out of the atmosphere and caused CO2 levels to fall. In time, the plagues abated, the farms were reoccupied, and the newly re-grown forests were cut, returning the CO2 to the atmosphere…Moreover, if plague caused most of the 10-ppm CO2 drops… it must also have been a major factor in the climatic cooling that led from the relative warmth of 1000 years ago to the cooler temperatures of the Little Ice Age.”
Like all good scientists, he notes the problems with his conclusions
“A more complete assessment of the role of plague- driven CO2 changes in climate change during the last millennium would require a narrowing of uncertainties in both the spatial and temporal occurrence of plague and in the amount of farm abandonment (and reforestation), as well as a resolution of the inconsistencies among the CO2 trends from different Antarctic ice cores.”
This kind of study will never be reported in the Atlantic; too much nuance.
It is not the correction for global warming I would suggest, an Earth Abides die off of humans.  But it is an fascinating association between infectious human deaths and global warming.
As the weather changes, for a week, a season, or a over longer period of time, the incidence and distributions of  infections change.  Infections could increase or decrease due to something as simple as temperature or humidity.
Or it could be more complex.  Increase rainfall could lead to more food, which could lead to a boom in the rodent population leading to more interactions of humans and mice and the next thing you know you have bubonic plague in India or Hanta virus outbreak in the four corners of the US.
The daily weather makes a difference in infection risk.  My favorite example is Legionella pneumonia, which increases shortly after thundershowers and humid weather.  It explains why we do not have a lot of Legionella in the NW despite all the rain; it is rarely hot and humid.
In Philadelphia  Legionella
“Cases occurred with striking summertime seasonality. Occurrence of cases was associated with monthly average temperature (incidence rate ratio [IRR] per degree Celsius, 1.07 [95% confidence interval [CI], 1.05-1.09]) and relative humidity (IRR per 1% increase in relative humidity, 1.09 [95% CI, 1.06-1.12]) by Poisson regression analysis. However, case-crossover analysis identified an acute association with precipitation (odds ratio [OR], 2.48 [95% CI, 1.30-3.12]) and increased humidity (OR per 1% increase in relative humidity, 1.08 [95% CI, 1.05-1.11]) 6-10 days before occurrence of cases.”
I ask the housestaff to look for Legionella after thundershowers and I usually get a case or two, although it may just be due to increased diagnostic testing.
Can you catch a cold when the weather is cold? Maybe.  It has been a topic of interest for years (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2279651/)
“The average outdoor temperature decreased during the preceding three days of the onset of any RTIs, URTI, LRTI or common cold. The temperature for the preceding 14 days also showed a linear decrease for any RTI, URTI or common cold.  (http://www.ncbi.nlm.nih.gov/pubmed/18977127).”
More interesting are the infections associated with El Nino oscillations, where the ocean temperatures vary on a 3 to seven to year cycle, leading to alternating wet and dry weather.  As a result
“In North America, El Niño creates warmer-than-average winters in the upper Midwest states and the Northwest, thus reduced snowfall than average during winter. Meanwhile, central and southern California, northwest Mexico and the southwestern U.S. become significantly wetter while the northern Gulf of Mexico states and Southeast states (including Tidewater and northeast Mexico) are wetter and cooler than average during the El Niño phase of the oscillation. Summer is wetter in the intermountain regions of the U.S. The Pacific Northwest states, on the other hand, tend to experience dry, mild but foggy winters and warm, sunny and early springs.”
Changes due to the El Nino lead to changes in the incidence of a huge variety of infections: an example, I think, from WHO.
Climate change will affect the distribution of disease vectors such as insects and snails.  Vectors may thrive with increased temperatures or they may die off, but more likely the vectors, like mosquitos, will move.  It has been estimated that half of everyone who has every died has died from a mosquito borne illness (I admit I heard this numoerous times at ID lectures but do not have reference, at least there is a solution . http://mashable.com/2010/02/12/mosquito-death-ray-video/).  As it gets warmer, mosquitos can either go up in elevation or North.  It seems that they are doing both.
– Dengue has appeared at higher altitudes than previously reported in Costa Rica (at 1,250m),and in Colombia and India (at 2,200m).The previous range was temperature limited to approximately 1,000 metres above sea level.
– In Mexico, the dengue vector (Aedes aegypti) has been detected at 1,600 metres; transmission of dengue was unknown above 1,200m before 1986. There have been cases of dengue near or above the altitude or latitude limit of transmission and would be vulnerable to the small increases in temperature that have occurred across these regions.
– Other examples of climate-related changes in the prevalence or distribution of pathogens and their vectors include the resurgence of Mediterranean spotted fever in Spain and Italy, the recent epizootic of African horse sickness in Iberia,the resurgence of plague in parts of southern Africa,increased incidence and geographic spread of algal blooms, outbreaks of opportunistic infections among seals,and the spread and establishment of pathogens and vectors in Switzerland.  http://archive.greenpeace.org/climate/impacts/erwin/3erwin.html
– Dengue has, by serology, infected 40% of the populations of Brownsville Texas, as the disease slowly moves north.
“In the fall of 2004, during a period of endemic dengue transmission, a cross-sectional survey was conducted in these two cities,4 and dengue incidence and prevalence were measured. In Brownsville, the incidence was 2%, which, if extrapolated to the 2005 population of the city (using the 95% confidence interval), projected between 837 and 5,862 recent infections. Similarly, the prevalence was 40%, with a range from 56,948 to 75,372; these values are relatively similar to those obtained from Brownsville in 2005. http://www.ajtmh.org/cgi/content/full/78/3/361”
More than mosquito born illnesses are changing in prevalence.  Hanta is increasing in Belgium.  There has been increased temperature which has lead to increased broadleaf trees, with increased seeds, with increased voles, which carry Hanta, which infected humans to cause renal failure (http://www.ij-healthgeographics.com/content/8/1/1).
Oceans are getting warmer and supporting infections.  Vibrio was not found in Alaskan oysters as the water was too cold.  The water temperature was always less than 15 C.  No longer.  The mean temperature has increased each year since 1997  and now supports the growth of V. parahaemolyticus with resultant outbreaks (http://content.nejm.org/cgi/content/abstract/353/14/1463).  Many other infectious diseases are increasing as well http://www.thebulletin.org/web-edition/columnists/laura-h-kahn/the-threat-of-emerging-ocean-diseases.
However, not all is doom and gloom.  Some infections may fade with global warming. For example, RSV may be disappearing as England warms.
“The seasons associated with laboratory isolation of respiratory syncytial virus (RSV) (for 1981–2004) and RSV‐related emergency department admissions (for 1990–2004) ended 3.1 and 2.5 weeks earlier, respectively, per 1°C increase in annual central England temperature ( and .043, respectively). Climate change may be shortening the RSV season. http://www.journals.uchicago.edu/doi/abs/10.1086/500208.”
Diseases that may increase in the US or become endemic again include malaria, dengue, and Leishmaniasis.  A 4 degree rise in temperature could allow dengue to exist as far north as Winnipeg and malaria to be in all of Europe. Seems to be a good trade off to me: more dengue and malaria, less RSV.
Good times for an infectious disease doctor.
These studies are representative of the literature, not a comprehensive review of the topic.  Personally, I find this adjunctive data compelling  support of global warming, at least over recent times (deliberately worded to not commit to the meaning of recent.)  This does not include all the other potential interactions between human behaviors and changes in the weather to result in an increase in infectious diseases.  Even simple local changes can lead to the unexpected increase in the risk of diseases.
“Adjustable rate mortgages and the downturn in the California housing market caused a 300% increase in notices of delinquency in Bakersfield, Kern County. This led to large numbers of neglected swimming pools, which were associated with a 276% increase in the number of human West Nile virus cases during the summer of 2007.”   http://www.cdc.gov/eid/content/14/11/1747.htm
All the neglected pools became mosquito breeding grounds, and the disease spread was exacerbated in part by a drought that altered bird populations from resistant finches to susceptible sparrows that were not immune to west nile, allowing the disease to spread.  The result, I suppose, of failed flock immunity.
Imagine how war, human migration, starvation will interact with climate change to increase or alter the spread of malaria, Tb and some infection that no one can predict.  If H1N1 proved anything, it is whatever new infection will sweep  across the county, it will not be the infection we predict. Who would have thought in 1989 that the next decade would see West Nile virus, never seen the the US, arrive to the continent in a migrating goose and become endemic.
Maybe its just the weather, the season, or the climate.  I think these are a few interesting infectious disease associations that lend credence to climate change.

“Conversation about the weather is the last refuge of the unimaginative.” – Oscar Wilde

I will state my bias up front.  I am convinced by the preponderance of data in favor of man made global warming.  At the most simplistic level, I can’t see how converting humongous tons of fossil fuel into CO2 and dumping it into the the atmosphere cannot have effects on the climate.  To my mind its like determining vaccine efficacy or evolution.  Plausible mechanism(s), good basic science, multiple studies using different lines of evidence that all come to the same conclusion.  There are lots of fine points and nuances to be worked out, but the basic truth is reasonable and well defined. Infectious diseases lend some validation to the concept that the world is warming, since with global warming comes a variety of infectious diseases.

It is one big IF:THEN statement.  IF global warming, THEN infections.  Of course  if the IF is not true, then the THEN doesn’t follow.

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