Philip Alcabes discusses myths of health, disease and risk.

CDC, Measles, and Propaganda

This week, the Centers for Disease Control and Prevention invokes measles  to make you feel guilty and frightened.

The agency announced on Thursday that there have been 175 measles cases in the U.S. in 2013, whereas only about 60 are seen in a typical year lately. Measles, the CDC press release says, “still threatens health security.”

Are they joking?, you might wonder. At a time when nearly 50 million Americans can’t get medical care because they don’t have insurance, and about 30 million will continue to lack health insurance even if the Affordable Care Act is fully implemented — at this point in American history, do the wonks at CDC really expect Americans to believe that an extra 100-odd measles cases represents a threat to the nation’s health?

No, they are not joking. CDC Director Frieden says:

“A measles outbreak anywhere is a risk everywhere.”

That sentence doesn’t exactly parse in standard English, but we get the point: be on guard, be on edge.

“With patterns of global travel and trade,”

Frieden continues,

“disease can spread nearly anywhere within 24 hours.”

This is not true, but truth isn’t at issue. Frieden is settling comfortably into his role as Minister of Propaganda for the unending War Against Risk, that existential danger to our well-being in which we are all supposed to be foot soldiers.

The media have responded as per their wont.  Measles is still a threat, there’s a spike in cases,  it’s about lack of vaccination, and so forth.

Here, the real story is that there’s no grave threat. There were over 100 measles cases in the U.S. in 2008 and over 200 in 2011. So it’s not at all clear that this year’s toll is out of the ordinary. And, of the 175 cases in 2013, most were acquired abroad. Measles transmission in the U.S. occurred in outbreaks among people who weren’t vaccinated for religious reasons, including 57 people in a Hasidic neighborhood in Brooklyn who were infected by a traveler who acquired measles virus in England, and 22 in North Carolina infected by a traveler returning from India.

That these outbreaks occurred among people who were not vaccinated reveals little about vaccination campaigns in the U.S. — religious exemptions have long been recognized for people who do not want their children to undergo immunization. And they have not been severe: a pregnant woman infected with measles in the Brooklyn outbreak miscarried, but there is no way to know whether measles was the cause. One adult was hospitalized with respiratory complications in the North Carolina outbreak.

It’s probably a good idea to be immunized against measles. Measles rarely causes severe illness, but not never. And there is plenty of measles in the world, although it is extremely rare in the U.S.  Immunization is like washing your kitchen counter tops.

But there’s no reason to sign up for Dr. Frieden’s army. Measles doesn’t threaten our health security (when it comes to threats to Americans’ health security, nothing comes close to Congressional Republicans!). We do not need to report our neighbors to the authorities if they aren’t getting their kids immunized. And we really don’t need any more inspections at airports. Our way of life is not under siege.

Influenza, Epidemics, and Science

Back in March, thinking about the controversy over Gain of Function (GOF) research on influenza viruses, I suggested that the debate isn’t really about science, nor

about morals, no matter what some self-important researchers claim.   The debate is about who will be able to control scientific research and who will benefit from the consequences (including, presumably, vaccines or other marketable preventive agents).  Don’t be misled by assertions that the debate over GOF research is about public health, or ethics.  It’s about the usual:  political power and profit making.

Now that a new flu virus, H7N9, has caused over 130 human flu cases in the far east, with 37 deaths (per WHO’s summary of 29 May 2013), the questions on GOF studies might seem to take on new significance.

The insightful Guenther Stertenbrink brought me up on my assertions about GOF research, saying

I don’t see that connection and motivation, how they  (signatories) might benefit from flu-research reduction politically or financially,  the “marketable agents”…  And don’t you think this should be discussed by hearing both sides,  giving them the opportunity to reply, with links etc. to support the claims  ? Have you contacted them ?
I’m trying to estimate the pandemic risks and I’m in the process of contacting them to see the letter to the ethics commission, how the signatories and 200 nonflu researchers were selected and approached, what their expertise is to judge and weigh and assess and quantify flu-specific benefits and risks.

Stertenbrink is working assiduously to assess both real pandemic risks and the scientific issues involved in the GOF research debate.  He is hosting a useful colloquy  and has also posted a timeline of commentary and findings.

But I’m sticking to my guns.  Guenther is perfectly correct when he intimates that many of the complainants who ask that GOF flu research be controlled or curtailed have nothing financial to gain.  But it’s not true that they have nothing at all to gain.  In science, and especially in science that bears on public health, controlling the narrative is of nonpareil importance.

The only reason why external commissions should be convened to assess the possible dangers of success of GOF  experiments is to make sure that the “right” people get to control the narrative.  Because, really, to claim that the actual danger to humans arising from transfering genes in flu virions is knowable and predictable is to misrepresent the deep uncertainty in assessing risk. 

There are three consequences of indulging in this misapprehended risk assessment.

First, it creates a false voice of authority.  “We know that bad things are likely to happen with probability X if experiment Y succeeds” implies that “we” (the experts?) have knowledge beyond what is actually available.  People who have claimed to have exceptional knowledge have done some very, very bad things to the world.  All claims of extraordinary knowledge of the future are to be rejected, on moral grounds, in a civil society.

Second, the claim to be able to assess the risks of successful experiments works against the inspired tinkering of science.  If our civilization want to have science — and I think it should — we are going to have to live with some unwanted disasters, and with some people (scientists, I mean) doing unseemly things.  We may reasonably regulate what they do, in order to prevent animals from being tortured or people killed for the sake of science.  But we can’t expect that science will always be “well behaved,” in the sense of a well-behaved mathematical function.

Third, claims that GOF experiments are unethical are really assertions that some other kind of science is ethical.  Some other science, in other words, is closer to an imaginary Platonic sort of correctness.  Science, as Paul Feyerabend argued, is anarchic.  Properly so.  But that means there are no hard-and-fast rules of Truth.

As a result, Truth in science is usually the thing that the most vocal and powerful people agree on. If certain kinds of science (GOF research, in this case) are declared off limits because the powerful people, such as those who are doing other kinds of research and think GOF research should stop, deem it to be “unethical,” then it is a sure thing that the truths of the powerful will be the only Truth.  But why shouldn’t everybody  have their chance at Truth?

I stand by my assertion.  The debates over GOF research, just like debates over “ownership” of the MERS coronavirus sequence or the carefully constructed fear  over whether the world is  sufficiently frightened about MERS, aren’t about science, or public health, or ethics.  They are about who controls the narrative.


Against Universal Flu Immunization

In a strong piece at CNN online yesterday, Jen Christensen points out that no European countries expect the entire population to be immunized against flu — unlike the US, where everyone over the age of 6 months is urged to get flu vaccine every year.

Why does CDC recommend (based on advice by the Advisory Committee on Immunization Practices in 2010) that all Americans — from infancy on up — get immunized against flu?

A few possibilities:

1.  Public health benefit?

No.  Over the past twenty years, flu-vaccine coverage — the proportion of the population that is immunized — has been going up progressively.  But flu hospitalization and mortality rates have been basically constant.  If mass immunization had any public health value, those rates should go down as coverage goes up

(A technical note: this means that coverage remains below the threshold needed to reduce influenza transmission population-wide, i.e., it isn’t high enough for herd immunity.  But that’s the point.  In order to be of public health benefit, flu vaccine would have to be accepted by almost everybody, every year.  And even that might not be enough:  For a nice explanation of why the efficacy of flu vaccine is limited, see Vincent Racaniello’s blog post.)

2.  Exceptional efficacy of the vaccine?

No.  Based on an observational study of acute respiratory illness patients published this month, the effectiveness of this year’s flu vaccine is 55% against illness caused by influenza type A (which accounts for about 80% of flu cases).  Effectiveness is 70% against type B.  Overall, the chances of being protected against symptomatic flu are less than two out of three.

Jefferson and colleagues found that the overall efficacy of  flu vaccines at reducing influenza A or B infection in children aged 2-16 is only about 65%, and that inactivated vaccines (i.e., the usual injection) had little impact on serious illness or hospitalization from flu-like conditions in this age group.

As with this month’s observational study, Jefferson et al.’s meta-analysis of multiple studies on flu immunization found that the inactivated vaccine had about 73% efficacy at preventing infection in healthy adults — but that efficacy can be as low as about 50% in years when the vaccine isn’t well-matched to the season’s circulating viruses.

Importantly, the Jefferson studies found that effectiveness of immunization — the prevention of serious illness or hospitalization from influenza-like illness — is very low.

There’s no sound public health rationale for encouraging everyone to be immunized against flu every year.

People who are likely to develop serious complications if they are infected can benefit from immunization.  But for most of us, immunization only reduces (by two-thirds) the already rather small chance of infection with influenza.  And it doesn’t protect us much from serious respiratory illness during flu season.

I commented in 2011 on public officials striving to help pharmaceutical companies profit from flu fears. And that’s what we’re seeing again this season — with exaggerated warnings and declarations of flu emergencies. Even though the latest national summary from CDC shows that less than 30% of all influenza-like illness is actually caused by flu this season — and that’s likely an overestimate, since it’s based on testing of more severe cases of acute respiratory illness.  And the surveillance data suggest that the season’s flu outbreak might already be past its peak.

Get immunized against flu if you’re worried.  But keep in mind that vaccination against flu is not going to help the public’s health, and it isn’t highly likely to help yours — it’s primarily your contribution to the profits of Sanofi-Pasteur, Novartis, GSK, or Merck.


The Myth of Normal Weight

Don’t miss Paul Campos’s commentary on overweight and obesity in today’s NYT.  Responding to the latest report by Katherine Flegal of CDC and coworkers, Campos points out that

If the government were to redefine normal weight as one that doesn’t increase the risk of death, then about 130 million of the 165 million American adults currently categorized as overweight and obese would be re-categorized as normal weight instead.

The report by Flegal et al., published this week in JAMA, is a meta-analysis of 97 studies on body-mass index (BMI) and mortality.  This new analysis found that mortality risks for the “overweight” (BMI 25-29.9) was 6% lower than that for “normal” BMI (18.5-24.9) individuals.  And those in the “grade 1 obesity” category, with BMIs from 30 to 34.9, were at no higher risk of dying than those in the so-called normal range.   Only those with BMIs of 35 and above were at elevated risk of dying, and then only by 29%.

In other words, people who are overweight or obese generally live longer than those who are in the normal range.  Only extreme obesity is associated with an increased probability of early death.

Flegal and colleagues already demonstrated most of these findings using administrative data, in an article appearing in JAMA in 2005.  There, they reported no excess mortality among people labeled “overweight” by BMI standards, and that about three-quarters of excess mortality among the “obese” was accounted for by those with BMIs above 35.

What’s notable about this week’s publication is that it has attracted the attention of some heavy hitters in the media.  Pam Belluck covered the JAMA report for the NYT.  Although her article seems more interested in propping up the myths about the dangers of fat than in conveying the main points of the new analysis, Belluck does acknowledge that some health professionals would like to see the definition of normal revised.

Dan Childs’s story for ABC News gives a clear picture of the findings, and allows the obesity warriors, like David Katz of Yale and Mitchell Roslin at Lenox Hill, to embarrass themselves — waving the “fat is bad” banner under which they do battle.  MedPage Today gives the story straight up.   In NPR’s story, another warrior, Walter Willett of Harvard, unabashedly promoting his own persistently fuzzy thinking, calls the Flegal article “rubbish” — but the reporter, Allison Aubrey, is too sharp to buy it from someone so deeply invested.  She ends by suitably questioning the connections of BMI to risk.

Campos’s op-ed piece does the favor of translating the Flegal findings into everyday terms (and without the pointless provisos that burden the NYT’s supposed news story):

This means that average-height women — 5 feet 4 inches — who weigh between 108 and 145 pounds have a higher mortality risk than average-height women who weigh between 146 and 203 pounds. For average-height men — 5 feet 10 inches — those who weigh between 129 and 174 pounds have a higher mortality risk than those who weigh between 175 and 243 pounds.

Is the hysteria about overweight and obesity is over?  I’m sure not.  In today’s article, Campos — who was one of the first to explode the fiction of an obesity epidemic, with his 2002 book The Obesity Myth — reminds us of a crucial fact about public health:

Anyone familiar with history will not be surprised to learn that “facts” have been enlisted before to confirm the legitimacy of a cultural obsession and to advance the economic interests of those who profit from that obsession.

There’s too much at stake with the obesity epidemic for our culture’s power brokers to give it up so quickly.  One day, some other aspect of modernity will emerge to inspire dread (and profits).  In the meantime, we might at least hope to see some re-jiggering of the BMI boogeyman.


Childhood Obesity: NYC’s Little Lies, Big Self-Congratulation

There is very little evidence that obesity is harmful to young children.  So I have to ask why NYC’s Department of Health and Mental Hygiene feels so strongly that fat schoolchildren should be forced to slim down.  And why it’s so eager to congratulate itself today on its policing of eating behavior — see reports by WSJ, Bloomberg, CBS (with photos of fat kids!), Huffington, and many other sources.  Why would the city’s health agency lie in order to claim that its jihad against a not-very-convincing evil has been successful?

The subject is a report published by CDC today claiming that obesity among NYC schoolkids in grades K through 8 has decreased 5.5%.

The city’s health commissioner, Thomas A. Farley has been true to the shades of history’s empty-headed warriors.  Farley announced that the drop in obesity prevalence is a “turning-point in the obesity epidemic” although it “does not by any means mark the end.”

A missed photo opp:  Dr. Farley standing on top of a fat child, holding up a sign reading, “Mission Accomplished.”

Farley is zealous about controlling people’s behavior and contemptuous of facts (nobody will ever accuse him of being an intellectual, either).  He blogs about his own work for the exclusive reading pleasure of Department of Health staffers.  This allows his staff to read the Farley-esque twist on truth.  One example for now:  in October of 2010, Farley’s blog exultantly told his staff that in 2009 the department had “immunized nearly 130,000 children [against flu] in more than 1,200 schools over a few months.”  Of course, health department employees are smart — many of them knew that the 2009 H1N1 vaccine Farley was talking about was a fiasco, far too late to make a difference, and aimed at an outbreak that was more of a whimper than a bang.

What about today’s “turning point” in the obesity war?  It’s worth noting that the supposed drop in obesity among NYC schoolkids is really just a very slight (1.2%) difference in the prevalence of obesity between 2006-7 and 2010-11.

A small difference between small numbers amounts to a large percentage difference.  So the 1.2%  actual difference magically turns into the advertised 5.5% — the proportionate change.

But the false advertising gets worse

1.  The prevalence of obesity in NYC was not measured multiple times on the same group of kids (to use epidemiology jargon:  this wasn’t a panel study).  Nobody observed fat children becoming less fat.  The city simply measured obesity prevalence each year on 5- to 14-year-olds who were in the school system.  So a high proportion of the 21.9% of kids who were labeled obese in 2006-7 would have been out of the age range for the 2010-11 assessment.

Plus, lots of kids leave the NYC school system after grade school (this has to do with Bloomberg administration’s bizarre system for preventing children from attending local schools).  So, even those children who haven’t aged out of the analysis by turning 15 would be absent from the data after a few years.  And, there’s also natural immigration and emigration.

Did the 2006 fat kids get slimmer?  Nobody knows.  The 2006-7 obesity prevalence among NYC schoolkids (21.9%) can’t be compared to the 2010-11 prevalence (20.7%).  If you were forced to compare these numbers, you’d say there had been a slight change — not a 5.5% decline.  There’s the first lie.

2.  The second lie is a little more complicated.   Since there is no widely accepted functional definition for childhood obesity, children are labeled obese if their body-mass index (BMI) falls into the upper 5% of the expected distribution of weight-for-height.  This expectation is based on an old-fashioned standard.  Fair enough.  But lots of distributions shift over time — SAT scores, human height, grades awarded at Ivy League colleges, and global average temperature, to name a few.

Sometimes the reason for an overall shift of this sort isn’t hard to specify (test prep, nutritional quality, relaxation of grading standards, generalized global warming, etc.).  But the main effect causing a shift in the distribution doesn’t explain why the few people who are in the upper reaches of the distribution are so far from the mean.  To say that fewer children are now above the high-BMI cutoff than in 2006-7 therefore the tendency of children to be fat is declining is a lot like claiming that because 2011 was cooler than 2009 and 2010, global temperatures are not really going up.

(Dr. Farley, I gather that statistics aren’t your strong suit, but surely when you witnessed that snowstorm we had this past October — an outlier if there ever was one — you didn’t conclude that the climate is actually getting colder, not hotter.  So what makes you think that a very tiny decrease in the proportion of kids with high BMIs means that the city’s kids are getting slimmer?)

3.  Claiming credit.   Attributing to the health agency’s own efforts a minuscule change in the proportion of kids who are in the upper tail of the broad BMI distribution requires self-congratulation so acrobatic as to stretch credulity.

Maybe there really has been some change in the city’s children since 2006.  Or in our food supply or buying habits.  Or exercising.  But to claim that such a change both caused the tiny decline in schoolkid obesity prevalence and that it was the result of the Health Department’s efforts — the exercising and the low-fat milk and the salad bars in the school cafeterias and so forth — is to commit the fallacy that Rene Dubos outlined (in his book Mirage of Health) nearly 50 years ago:

When the tide is receding from the beach it is easy to have the illusion that one can empty the ocean by removing water with a pail.

Is childhood obesity really a health problem?

It’s not crazy for health professionals to be concerned about body mass.  Obesity might be really bad for some people, and somewhat bad for many.

But those people are adults.  Why are health agencies like NYC’s so riled up about obesity in little children?

So far, there’s no strong evidence that obesity in younger children predicts any real harm later in life, other than being a fat adult.  With adults, several signs of impending debility are more commonly found in the obese than the non-obese, such as hardening of the arteries, fatty liver, sleep apnea, and diabetes.   And with adolescents, there’s some evidence that those who are obese develop similar warning signs.  But not younger kids.

A 2005 BMJ paper reported only social effects in adulthood (being unemployed and being without a romantic partner) of early obesity.  Similarly, one cohort study carried out in Newcastle upon Tyne found little evidence that fat children became fat adults, and no evidence for predictors of illness in adulthood among those who had been overweight as children — although other studies have shown correlations between adolescent obesity and adult problems.

For kids below age 15, the most visible problem with obesity is that it occurs most commonly among the poor and dark-skinned.  This bothers the obesity warriors.  In fact, not only is obesity more common in African- and Hispanic-American children in NYC, even the slipshod standards of today’s report on NYC schoolkids can’t be manipulated to show that obesity is declining among these children.

As with all holy wars, from the Children’s Crusade through the U.S. invasion of Iraq, the warriors aren’t really concerned about principle.  Something about somebody got under their skin.

Here’s how I answer my own question:  I guess the obesity crusaders don’t like it when the children of the wealthy look like the children of the poor.  They think that white kids on the Upper East Side aren’t supposed to look like kids who live in the Bronx.

It isn’t about health, in other words.  It isn’t even about obesity.  The “childhood obesity epidemic” is about making sure society looks the way that the health crusaders want it to look.