# 1055
The past few days the biggest news on the Avian flu front has come from the announcement that researchers have isolated an antibody that might work against multiple strains of the H5N1 virus. This, we are told, may pave the way to a preemptive avian flu vaccine.
This report from the The Standard of Hong Kong is pretty typical, although to their credit, this paper has dropped the `beat bird flu before it begins' headline that many newspapers have used over the past couple of days.
Still, the underlying message is we are on the verge of having a vaccine that can prevent a pandemic. But are we really?
First the article, then a reality check.
New vaccine to jump gun on avian flu
Saturday, August 11, 2007
Researchers studying bird flu viruses believe they may have found a way to vaccinate people before a feared influenza pandemic.
Experts have long said there is no way to vaccinate people against influenza until a strain evolves. That could mean months or years of disease and death before a vaccination campaign.
But a team at the US National Institute of Allergy and Infectious Diseases in Maryland and the Emory University School of Medicine in Atlanta said they may have found a shortcut.
The reason we don't have a vaccine available to stop an influenza pandemic, we are told, is because you can't start manufacturing one until the exact pandemic strain is identified. Viruses mutate, and a vaccine based on an older virus might not be effective against a mutated strain.
And that is true, as far as it goes.
But of course, that isn't the only reason. It is just the easiest one for governments to explain. Most people understand this problem, and accept that vaccine production can't begin until after a pandemic erupts. It sucks, but they accept it.
But what if you could remove that barrier? What if you could produce a vaccine in advance that had a good chance of being effective against a mutated H5N1 virus, would the governments of the world do so?
Could they, even if they wanted to?
And if they did, would they really be willing to administer this experimental vaccine to billions of people prophylactically in order to `beat a pandemic before it starts'?
Using today's egg-based technology, we have the global capacity to produce about 500 million trivalent doses of vaccine a year. If a monovalent vaccine could be produced instead, then theoretically 1.5 billion doses might be produced over 12 months.
Of course, no other influenza vaccines could be produced during this time, and without a seasonal flu vaccine, that would probably lead to many thousands of deaths from non-pandemic flu.
But, if all of our resources were devoted to this new vaccine, since most vaccines have required 2 shots, 30 days apart, this might be enough to inoculate 750 million people. Or roughly 12% of the world's population.
Hmm. I'm beginning to sense a problem here. Nearly 90% of the world's population still wouldn't see a vaccine in the first year.
Complicating matters is the fact that most vaccines (and I'm assuming this would hold true for this new one, as well), lose their effectiveness after a few months. The immune response wears off over time. Perhaps not completely, but the level of protection begins to drop after 6 months or so.
And that means that booster shots, every year or so, may be required. That would drastically cut down on the number of people that could be inoculated in subsequent years.
Now perhaps the new cellular based manufacturing techniques currently under development will solve this production problem. They hold the promise of greatly enhancing our ability to produce vaccine in quantity. While not quite ready for prime-time, these techniques could be online in the next few years.
But then comes the decision of whether to inoculate people with an experimental vaccine against an influenza strain that may, or may not, cause the next pandemic. As many of you will recall, that decision was made in 1976 with the Swine Flu, and the results were less than satisfactory.
Severe reactions to influenza vaccines are believed to be extremely rare, despite the bad name the Swine Flu vaccine earned 30 years ago. Still, if only 1 person in 100,000 experienced a problem, that could equate to nearly 3000 potential lawsuits in the United States alone.
That is a lot of liability.
It would take an enormous amount of political courage to spend billions of dollars to divert our current seasonal influenza vaccine production to an experimental vaccine for a pandemic strain, and then risk prophylactically inoculating large segments of our population before a pandemic erupted.
The lack of a seasonal vaccine would certainly cost lives. And any adverse side effects to this experimental vaccine would be sensational fodder for the press, just as it was in 1976. The decision to put all of our eggs into an experimental vaccine basket would be very tough for any government to make.
We've been conditioned by movies and television shows to believe that scientists can, at the last minute, create some medical miracle that will always save us from the brink. It's a nice fantasy, but basically it's a plot device used to wrap up a dramatic presentation in an hour or two.
It has, however, a long history.
In ancient Greek plays, it was common to have an improbable character or event introduced suddenly at the end of a play to resolve whatever thorny problem remains. Deus Ex Machina, literally God out of the machine, comes from the plot device of lowering a God from the rafters onto the stage to solve all of the problems.
There are a lot of problems that would have to be overcome before any scientific breakthrough in vaccine research could be used to prevent a pandemic. They aren't impossible to solve, of course.
But we would need time, luck, and immense political courage on the part of our leaders to make it happen.
And a God descending from the rafters wouldn't hurt, either.
