Friday, December 22, 2006

All The Junk That's Fit To Print


#260

 

 

Today, we get an editorial from Steven J. Milloy of the Competitive Enterprise Institute, and published on FoxNews.Com entitled `One Flu Over the Cuckoo's Nest'.   In this piece on the `junk science' of avian flu, Mr. Milloy takes on the Lancet Study released yesterday and berates it as being alarmist.  While I've already weighed in on the deficits of that report here, my problems were that it glossed over the effects a pandemic would have in the developed world, not that it was overly alarmist.

 

So be it.  A difference of opinion.  That's what makes the World Wide Web go round.

 

And I'd leave it at that, except Mr. Milloy's argument that the next pandemic must be mild, such as the ones we saw in 1957 and 1968, isn't even based on `junk science'

 

It's based on nonsense.

 

Quoting Mr. Milloy

 

But perhaps the researchers’ choice that most reveals their apparent desire to come up with a scary – rather than a realistic – death toll from pandemic flu is their decision to use the 1918 pandemic flu data in the first place. There were, after all, two other more recent and, in all likelihood, more relevant pandemic flu outbreaks in the 20th century.

 

There was the 1957-58 Asian flu pandemic that killed somewhere between 1 million to 4 million people. The 1968-1969 Hong Kong flu killed an estimated 750,000 people.

 

Now if one wanted to estimate a death toll from a hypothetical pandemic flu in today’s world, it seems as though data from the Asian and Hong Kong flu pandemics would be much better starting points than the far more uncertain data from a chaotic period almost 90 years ago. That presumes, of course, that one is interested in more realistic (albeit smaller) estimates that better reflect modern conditions as opposed to overblown numbers aimed at producing scary headlines.

 

Now this almost sounds like it makes sense. After all, Mr. Milloy points out our medical knowledge is greater and we now have antibiotics we didn't have in 1918.  Our ability to combat the next pandemic has certainly improved over the past 90 years.  The next pandemic should be, by all rights, even less of a problem than 1968. 

 

Shouldn't it?

 

Only if you ignore all the science behind pandemics, which Mr. Milloy conveniently manages to do.

 

The reason the 1918 Spanish Flu was so devastating, and the 1957 and 1968 pandemics relatively light,  is well known.  At least to scientists.  Mr. Milloy apparently is unaware of the reasons, so I will explain them as simply as I can. 

 

No need to thank me, Mr. Milloy.   I live for this sort of thing.

 

The reason why seasonal flu's are relatively mild for most of us is that they are genetically similar to flu's of years past.  We've all been exposed to them, and have developed antibodies that recognize them.  It is only when a radically different flu surfaces that a pandemic occurs. And the virulence of any pandemic is determined by just how different the new strain is from what we've already been exposed to.

 

The H1N1 virus, the one that caused the Spanish Flu of 1918, was a novel virus to which most, if not all humans had no immunity to.  There is some evidence that perhaps sometime in the mid 1800's, a similar virus may have made the rounds, but for those under the age of 65, there was no history of exposure, and therefore no immunity.   Whatever flu was in circulation before 1918, it was apparently genetically quite different from the H1N1 virus that emerged that year.

 

The Spanish Flu, was therefore a killer of monumental proportion.

 

The 1957 pandemic, the so-called Asian flu, was not an entirely new flu. In fact, it was a product of reassortment between an unknown avian strain of flu and the H1N1 strain which had been in wide circulation since 1918.  It retained much of its genetic material from an existing strain to which we all had been exposed.

 

In other words, it wasn't our modern society, or our medical advances that made the Asian flu less of a killer; it was the genetic makeup of the virus itself.

 

In 1968, the Asian H2N2 flu, mutated through antegenic shift and became the even milder Hong Kong Flu, or H3N2 virus.  Once again, this virus's roots go all the way back to the 1918  H1N1 virus, and so the effects of this virus were considerably dampened.

 

Today, the H5N1 virus that now looms is, like the H1N1 virus of 1918, a novel influenza strain; one that we have no immunity to.  This is why, of the roughly 260 people who have been diagnosed as having contracted it, 60% have died.

 

If we were looking at a genetically similar virus to the ones currently in circulation, a product of antigenic shift from the H3N2 virus for instance, then your point would have some validity.  But we aren't.

 

While you deride talk of a devastating pandemic as being based on  `junk science', you are only half right.

 

It's based on science.

 

Now, will the H5N1 virus turn into the next pandemic?  

 

We don't know.  And if it does, we honestly don't know when it will happen. It could be next year, the year after, or perhaps never

 

It still needs to pick up a few mutations in order to make it easily transmissible from human to human.  How that happens will determine how virulent it remains.  It could, through reassortment, obtain genetic material from the currently circulating H3N2 virus and that might help attenuate the lethality of the virus. 

 

We are hopeful that, if it becomes a pandemic, that is how it will happen.

 

But what we do know is, that if the H5N1 virus manages to become a pandemic strain, and does so without picking up genetic material from a flu to which we have had previous exposure, the odds are that it will be a very bad pandemic strain.

 

And that is the reason for the heightened concern.

 

Virology is a fascinating subject, and while the complexities of it elude even the best scientists, the basics are fairly easy to comprehend. Assuming you take the time to learn them.

 

Hey, if I can do it, Mr. Milloy.

 

So can you.