Sunday, March 19, 2006

The Siegel has (crash) landed

Marc Siegel, the XY counterpart to nay-sayer Wendy Orent, is at it again. This time he is criticizing Robert Webster, one of the world's most experienced and best known flu virologists, for making unscientific statements. Truth to tell, it is hard for many of us to understand the basis for Webster's declaration that "50 percent of the population could die" in the event of an avian flu pandemic, but it may be that the context is missing. I rather doubt he was speaking of 50% of the world's population or even 50% of those infected. It is more likely he was referring to the current case fatality proportion of 50% which probably overestimates the true fatal proportion as we do not have a good way to count the denominator (the total of those infected or even those clinically affected). My own experience with news media has always been that half or more of your narrative gets lost, and if it is an important half the meaning is altered. But Siegel is certainly within his rights to use what is on the public record. But that's where I stop cutting him any slack.

Siegel, like Orent, has made a career out of being a contrarian. Not always a bad thing, but, like his criticism of Webster (who knows more about flu than Siegel will ever know), it should have some basis. Siegel says Webster knows about test tube virology but not about how the virus will behave in the real world. I don't know what the basis for this claim is, but I can tell you Siegel is no epidemiologist. I knew him many years ago and he is a dilettante who now hawks his books describing how everyone else is wrong. The pot calling the kettle, etc.

Consider this:
By [Webster's] estimate, we should be destroying every bird in the world right now before we all perish in a pool of pathogens. Webster's statement is the latest Hitchcockian pronouncement about H5N1 bird flu, a virus that is deadly in birds. But humans are different. We are protected by a species barrier, and serological surveys conducted in 1997 in Hong Kong and since have detected antibodies in thousands of humans who never got sick, showing that bird flu isn't as deadly to the few who come in contact with it as has been reported.
Since the relative paucity of seroprevalence data is one of the scandals of avian flu research, I would be glad to know of the papers that show this. There is a rundown of seroprevalence studies done at The Flu Wiki which Dr. Siegel may wish to consult before making further mistakes. Moreover, he follows it with an even more doubtful statement:
In fact, the growing immunity to H5N1 worldwide may lessen the outbreak in humans even if the dreaded mutation does occur. As time passes, the chances of this mutation appear less rather than more likely. (The Spanish flu, by comparison, mutated before killing a lot of birds.)
"The growing immunity to H5N1 worldwide"? This is not science. It cannot even be called wishful thinking. It is fantasy. There is also no data on bird die-offs in 1917 - 1918 that I know of. Maybe Dr. Siegel would like to supply a reference. This is followed by some pig mixing vessel crap.

Siegel further says that the 1976 swine flu episode resulted in the paralysis of more than 1000 cases because of a rushed vaccine given to 40 million people. I'll leave aside the fact there has been continued debate as to whether the vaccine was responsible for those 1000 cases of Guillain-Barré Syndrome Siegel claims and assume it, arguendum. That's 25 cases per million vaccinated, or 2.5 cases per 100,000. The incidence of GBS without vaccination is estimated to be 1 to 2 per 100,000 per year.

But the swine flu argument is moot in any case. We don't have a bird flu vaccine yet and won't until at least the first wave of a pandemic will have passed. At that point we will be grateful for any small risk of GBS compared to the risk of influenza. Vaccines today are also safer than in 1976. So this isn't really a serious argument and likely not even a factual one.

The serious argument is that Siegel continually perpetuates an extremely dangerous myth, which is that the public shouldn't be allowed to hear the full range of informed opinion for fear it will engender panic (and Rob Webster's opinion is a lot more informed than Marc Siegel's by any measure of "informed"). Panic, which is rare, results when people believe important information is being withheld. In my 40 years in medicine and public health I have seen few instances (maybe none) where significant panic was the consequence of providing reasonable health information, even if the information is scary. Nobody can deny the news media like to dramatize things. We have a free press and that is inevitable. But the fear of panic which so consumes the Siegels and Orents (and many health officials) is itself dangerous because it leads them to reassure without foundation. This leads to suspicion and loss of credibility when events turn out differently (as they so often do). And credibility is a health official's most precious asset. You should take risks to keep it. There is a great deal of work to do if we are to be prepared should a pandemic happen. Siegel is not helping anyone get ready.

Both Siegel and Orent have significantly modified their earlier views that bird flu was a Chicken Little game. They have been forced to do so by events. But they both continue to garner attention and sell their articles and books with the gimmick that they are the sane voices of reason, yet neither are bird flu experts. Consider that most informed scientists are saying we should worry.

If what Siegel was doing didn't create public confusion, I'd ignore him. Which is maybe what I should have done in the first place. But he's such an aggravating pipsqueak.