Friday, June 4, 2010

Swine flu: Not a Hoax, But ....

UPDATE June 5: the EU smells a rat, and it works for WHO.

I get a sense that there is now a new push-back on last year's swine flu. It looked like a fiasco at the time--so few deaths it was actually an unusually good flu season--with government agencies constantly nagging us to get vaccinated.

So the New Scientist runs a short piece by Debora MacKenzie. "Don't worry folks, it wasn't a hoax."

Critics now allege the flu was less deadly than normal flu, meaning vast sums of public money were wasted on nothing more than a scare. Some even claim that it was a conspiracy to boost vaccine company profits.

MacKenzie doesn't exactly provide a ringing rebuttal to the statements by "critics."

First and foremost, the notion that swine flu is not so deadly is an illusion caused by incomplete statistics: it certainly rivals normal flu, and its impact so far exceeds some previous flu pandemics.

Wow. It "rivals" normal flu, and it has an "impact" (deaths? serious cases of illness? mass hysteria caused by official exaggerations?) that exceeds "some" (how many?) previous pandemics. Scary stuff.

Later we find this:

Even though early reports from Mexico suggested a high mortality rate, when the virus hit the US in April it did seem fairly benign. Should the vaccine plans have been shelved at that point?

Nobody knew in April last year what swine flu would be like six months down the line, at the start of the winter flu season in the northern hemisphere. It could have turned very nasty - and to have vaccine ready for that eventuality meant making it immediately.

So it's not so much that the virus actually was nasty--it was "fairly benign"--but that it could have been, and it was wise to go ahead with large-scale production of vaccine. Her argument seems to be that no one could have known any better, the cautious approach, i.e. encouraging large-scale vaccination, was the best, and people who criticize what was done are putting people at risk in the future.

Governments have pandemic vaccine orders in place largely because they are worried about bird flu. Nobody disputes that this is the correct strategy. If this highly lethal virus starts spreading readily in people, it could be worse than the 1918 flu pandemic, which killed millions. But other flu viruses are potential pandemic threats too.

Flu evolves, especially when it is blasting through millions of new hosts.

We know the 1918 virus got worse as it spread.

But is this whole picture true? That a terrible flu pandemic is more or less inevitable, that it is likely to be bird flu but might be another kind, and that the worst kind is one that hasn't been around (or one like it hasn't been around) for a long time--so we have a population mostly lacking antibodies against it? If this is all true, anyone criticizing the attempt to vaccinate much of the population must have been very irresponsible.

The Toronto Globe and Mail discusses a report by Ontario's present Medical Officer of Health. Why was there a mis-match between demand for flu vaccine and supply? At an early stage, there were huge, highly publicized line-ups of frustrated people. Only a few weeks later, vaccine was going begging. Overall, fewer people were vaccinated than officials had expected and hoped.

Health experts say the low rates point to failings on the part of provinces. Alberta, for example, initially ignored an agreed-upon priority list and said it would vaccinate anyone who showed up, forcing clinics to close abruptly. Ontario did the same, resulting in waits as long as six hours. Experts say confusion reigned, and the lack of co-ordination shook public confidence in how the pandemic was being handled.

What is more, anti-vaccine advocates or doctors expressed skepticism about the severity of the pandemic. As much as they tried, health officials, mainly in larger provinces, could not persuade the public to get vaccinated.

“In a small province you can control the message much easier than in a larger place where … you will always find a professor of something or a previous chief medical officer of health or someone else to say they disagree, the vaccine is not safe or the adjuvant is not properly tested or the pandemic is not so bad so why bother and so on,” said Paul Van Buynder, deputy chief medical officer of health in New Brunswick, a province that vaccinated 65 per cent of its population.

“I think it’s very difficult to get 75 per cent of the public to go and do something if the message they’re getting is actually a mixed message.”

Dr. Richard Schabas, a previous Medical Officer of Health (and probably the one referred to above), has questioned all of these beliefs beginning in April 2009.

See here, here, and here.

Schabas says that in general, viruses mutate in the direction of being less virulent--evolution would favour a virus that doesn't kill its host. The exception that Schabas doesn't spell out is when a population shifts from rural to urban, or simply becomes more congested: more hosts, less of a price to be paid if a virus becomes highly virulent. He does mention the 1918-19 flu, and he says he doubts that it was the same virus both years. The first year was fairly mild, the second year much worse--probably a different virus, which again became increasingly less virulent as time went on.

Bird flu a few years ago was a bust, as was SARS, and there have been others. Public health people and epidemiologists go for big dramatic scares--partly to add to their budgets, and partly because they don't want to be stuck with the topics of bad cheese and the proper use of seat belts. But they are crying wolf.

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