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Judith Anne I posted this story separately but since I dont know how to 'link' to other articles here I'm going to repost the news story here since it may be relevant to your point...hope that is ok.

Experts mull possibility of vaccine protection against pandemic flu strains
CP ^ | 24/04/2005 3:48:00 PM | Canadian Press

Posted on 04/27/2005 11:53:34 AM EDT by FYREDEUS

TORONTO (CP) - When the next influenza pandemic hits, vaccine will be the key defence for countries that can afford it. But there will be inevitable if agonizing months between the emergence of a pandemic strain and the point when vaccine is ready to be plunged into arms.

Some influenza experts, though, have started to debate whether it's really necessary to wait for a pandemic to ignite before moving to protect people against virus subtypes on flu watchers' Most Feared list.

Wracked by concerns the world might be watching the unfolding of a pandemic, they are searching for out-of-the-box solutions to reduce the devastation to human health and the global economy that one would wreak.

Dr. Jesse Goodman is among those mulling over the notion of trying to create some population immunity to threatening flu strains during interpandemic times.

The idea is still "very exploratory," admits Goodman, director of the Food and Drug Administration's centre for biologics evaluation and research, which regulates vaccine production and sales in the United States.

"I think there is an opportunity to think about: Can we prepare and provide some protection not in a crisis mode, but more ahead of time? Ahead-of-the-curve kind of mode," he suggested in a recent interview from Washington.

"I think this is a strategy worth considerable thought and discussion. . . . (But) it's not something one would just do without a lot of thought and evaluation."

The idea would most likely entail adding a fourth component to the annual flu shot, which currently protects against the three flu strains - two influenza A and one influenza B - experts predict will be dominant in the coming flu season.

Adding a fourth strain could awaken or prime the immune system to viruses it's never seen before. Like the H5N1 strain smouldering in Southeast Asia. Or the H7N3 strain behind British Columbia's 2004 avian flu outbreak. Or H2N2, the 1957 pandemic strain recently sent in unlabelled vials to more than 5,000 labs around the world.

(While the flu world fears H5N1's lethality, some experts argue H2N2 is the top contender for the next pandemic strain because of its proven ability to infect and spread among humans.)

It is widely believed people would need at least two shots - a primer and one or two boosters - to get good protection against a flu strain their immune systems has never battled.

This idea would see a generic primer to H5N1 or H2N2 delivered well in advance of need. Once a pandemic starts and a vaccine targeting the specific strain is produced, the booster or boosters would be administered. If a large segment of the population was pre-primed, vaccine production time could be cut dramatically.

University of Ottawa flu expert Dr. Earl Brown says the approach could give pre-vaccinated people "a leg up."

"It has some merit in that you should have some (protective) advantage," Brown says, adding that even without the booster shot, people who'd been primed might have some protection. "Maybe some people wouldn't get as severely diseased."

The head of the World Health Organization's global influenza program also sees the theoretical appeal of the notion.

"Logistically, it could make sense that during ... peace times like now you vaccine everybody and then when it comes to mass vaccination needs . . . you'd only need to apply one dose," says Dr. Klaus Stohr.

But Stohr is also quick to point out what might be the single biggest impediment to the idea - the issue of liability. While flu shots are considered to be among the safest medical interventions available to public health, no vaccine or drug is risk-free.

The flu community knows that too well, having learned the lesson the hard way during from the swine flu debacle. In the spring of 1976, four U.S. Army recruits fell ill with what was discovered to be a swine flu similar to the 1918 strain that caused the worst infectious disease outbreak in recorded history, the pandemic know as the Spanish Flu.

Fearing the 1918 virus was readying itself for a new assault, the U.S. government mounted a mass vaccination campaign aimed at protecting every American.

Swine flu never took off, but another health threat did - Guillain-Barre syndrome.

A small but significant number of people who got the swine flu shot developed the potentially fatal neurological condition, resulting in major lawsuits. To this day, the rare syndrome remains linked to influenza vaccination, though only one study has shown an association and then only at the rate of one case per million people vaccinated.

Still, swine flu instantly comes to mind when the flu community starts discussing the ethics and liability concerns raised by the notion of vaccinating people against a theoretical risk.

"The bar does rise," Brown admits.

"If you vaccinate your whole country, you've got to be concerned that everybody for the next two or three months is going to blame whatever bad happens on the vaccine."

Vaccine expert Dr. John Treanor sees other problems as well. Treanor thinks pre-priming might actually work, though it would need to be proved through testing.

But he says with current flu vaccine production limitations - old technology, capacity to make vaccine for only a fraction of the world's populace - "it's probably not going to fly.

"It's been quite difficult just to make the regular vaccine. Add another component, it just makes it that much harder. It might make it so hard it couldn't be done," says Treanor, director of the vaccine treatment and evaluation unit at the University of Rochester, one of three centres testing an experimental H5N1 vaccine for the U.S. government.

Stohr points out another issue. Pre-priming, if it worked, is only really an option for affluent countries.

"We must also not forget that we are talking about a privileged part of the population. Those who can already afford the seasonal vaccine would have access to it. And the others would again draw the short straw."

Goodman knows all these arguments, but feels the notion is still worth exploring.

"It needs a careful discussion" he says.

"But in the long run, if you really do think about it more optimistically, what you realize is that with good surveillance systems we do have the possibility of knowing what are potential pandemic threats and thinking about these kinds of strategies."