At the beginning of the epidemic, with lots of deaths in Mexico, the government decided to procure enough vaccine for all who wanted it, as fast as possible, and give it out for free. Had this epidemic been as deadly as first feared, we would all be grateful for those decisions.
Anticipating the difficulties of vaccine production, and the slowness of the hens' egg process, the government decided to use a number of strategies and companies for vaccine production. It chose to order a mix of live vaccine (faster, cheaper production), cell culture-grown vaccine (faster production) and hens' egg production (tried and true, though slower). Had one process gone very well, and if the epidemic had been more deadly, more vaccine made by the fastest method could have been obtained to speed availability.
Five companies were given vaccine contracts. This would have (and has) resulted in at least some timely vaccine successes.
Novel adjuvants were purchased: enough for the whole country. Had the virus been very deadly, an adjuvant would have expanded the (injectable) vaccine supply by at least a factor of four.
When it turned out the virus wasn't all that bad, the US government wisely chose not to use adjuvant, knowing this would slow down vaccine production, but would add a significant measure of safety. This was done despite calls from WHO to use adjuvants, and despite decisions by most other developed countries to include them in swine flu vaccines.
UPDATE: Dr. Margaret Hamburg, FDA Commissioner, "defended the agency's decision not to use an additive that could have stretched swine flu vaccine supplies" at the Reuters Health Summit on November 12. More from Reuters:
Last but not least, despite loud calls for more and faster vaccine availability, the feds have not rushed out a poorly manufactured product. Think that never happens?"Adjuvanted vaccines contain an additive to boost the immune system response and need less of the active ingredient than the unadjuvanted types approved by the FDA.
But Hamburg said they have not been widely tested and that the agency did not want to risk using them when standard vaccines worked well with a single dose.
"Had the shape of epidemic or the characteristics of the virus and the disease required it, we would have moved toward an adjuvanted approach," she said.
"Europe took a little bit more of a risk. Yes, there was experience with an adjuvanted vaccine but it was really only used in the elderly and there wasn't experience with that vaccine in other populations, including pregnant women and children."
Bacterially contaminated flu vaccine from England was about to be distributed in the US in 2004 when the UK Medicines and Healthcare Products Regulatory Agency (not the FDA, which had averted its eyes to the problem) pulled the manufacturer's license. Remember how we lost half the flu vaccine supply that year? Then the same problem recurred the next flu season.
Want to read a scary timeline of how the US public nearly received this potentially deadly, contaminated vaccine? FDA denied it had been warned by UK officials of the problems weeks before the license was pulled. Yet the Liverpool plant was notorious for problems. (I personally returned vaccine delivered to my office free (by the state) from this same factory, after reading the FDA's inspection report of its failures.)
The company at fault, Medeva, then Chiron Corp, was later purchased by Novartis. Novartis has the current contract for half the US swine flu vaccine supply, and again, there are apparently significant problems causing delays.
The agencies responsible for vaccine regulation and testing are now taking the time they need to get this right. Injection bypasses all the body's protective mechanisms, and the material injected needs to be "the good stuff." Safety and quality must trump convenience and expedience.
This is our dress rehearsal for a really serious pandemic. Let's learn from this how to do it better next time. The US could have done it a lot worse.
Postscript: This post may surprise some readers, but what I find necessary is the ability to balance benefit and risk. If a disease is very virulent, you may need to take more chances with the remedies. With swine flu, a relatively mild pandemic, there is little justification to take big risks on prophylactic measures.
UPDATE (Nov. 17 NY Times): "At a hearing before the Senate Committee on Homeland Security and Governmental Affairs, representatives of the Centers for Disease Control and Prevention, the Department of Health and Human Services and the Department of Homeland Security argued that they were right not to put immune-boosting adjuvants in the vaccine even though that could have quadrupled the number of doses available now..."
2 comments:
Can you please expand on your comment that an adjuvanted vaccine would have been less safe? Is this related in any way to the squalene based adjuvant that was also present in the anthrax vaccine?
I live in Canada and been vaccinated last week with the adjuvanted H1N1 vaccine from Glaxo/Kline. I usually do get Flu shots every year but I have never experienced side effects ( at least never connected any dots...). But this time it's been almost a week and I still have a very mild fever of 37.0 C ( 1st few days after the shot it was 38.5 C and no amount of Tylenol helped)
The unajuvanted vaccine had a reported 45% systemic reaction rate.
http://www.medscape.com/viewarticle/709468?src=ptalk&uac=32611CG
With adjuvant I would expect it to be higher. I have been told by recipients in my community of 5 plus days of fever, muscle aches, headache and mild joint swelling. These side effects can be anticipated to occur in a minority of recipients of either type of vaccine.
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