[lit-ideas] Re: flu vaccine
- From: Eternitytime1@xxxxxxx
- To: lit-ideas@xxxxxxxxxxxxx
- Date: Wed, 27 Oct 2004 00:14:14 EDT
In a message dated 10/26/2004 12:27:17 PM Central Daylight Time,
JimKandJulieB@xxxxxxx writes:
Can anyone vouch for
the validity or lack thereof of any of it?
Julie Krueger
wondering
Hi,
This was in the Kansas City Star: Do know that we (on a different list)
were talking about how the profit margin was not *quite* as high (though one
of
the members has a husband who went with his brother [who is a sales
pharmeucetical rep] on a sales trip to NYC where they each had their own room
in a
posh hotel and $500 dinners [per person] each night [for a week]. Apparently
the brother lives like that all the time and his brother was a bit stunned by
it all. I knew from a couple of people that I know who used to be in that
profession that it does, indeed, pay well, but I had not idea it paid *that*
well. (they are now in the tv industry--their egos needed that more than they
needed the money...though they do fine with the money, too...guess I
understand now just why they would sigh while remembering...)
I have decided that if Bush wins ... I need to change professions. I will
then be able to take care of my friends and their kids...esp those who need
medicine <g>. Julie, your problems will be over! [of course, I might have a
few ethical issues to deal with but I'm sure that all of you will help me,
right?]
Anyway, don't know all about what you wee asking in terms of validity of
what you read, but this verifies some of it...
Telling Robert Paul that World Series tickets are going $1000 apiece in St.
Louis,
Marlena in Missouri
Posted on Mon, Oct. 25, 2004
Vaccine Production Relies on Quaint System
MARILYNN MARCHIONE
Associated Press
SWIFTWATER, Pa. - The quaint system of producing flu vaccine
based on seasonal egg-laying has harsh implications for what would
happen if new batches had to be made in a hurry to fight a super-
strain pandemic. At best, it would take half a year.
And since chicken flocks for next year's vaccine are already
established and plants already run at full capacity, it's unclear how
much Aventis Pasteur or any single company can goose up
production to cover a shortfall like this year's loss of Chiron Corp.'s
vaccine.
As Chiron executive Dr. Kevin Bryett said in an interview two weeks
before its British factory was shut down: "If the market was to
change dramatically, it is almost impossible to turn up production.
The primary issue is access to the eggs. Large numbers of birds
cannot be obtained immediately. It's not something you can just go
down to the shop and buy, eggs off the shelf."
A visit to Aventis, America's only flu shot maker, reveals how much
fragile Americans depend on an eggshell-fragile system to protect
them from a killer disease. The Associated Press was allowed
inside last week for a rare, firsthand look.
As the nation struggles with a historic shortage of flu vaccine, the
last batches of this year's supply are being bottled at a slickly run,
modern factory in the Pocono Mountains.
A little to the west, in Amish country, next year's doses are already
in the works. At the moment, they have two legs and soft, downy
feathers. By January, they'll be laying millions of eggs for flu shots.
There is far more horse-and-buggy to vaccine production than just
the Amish wagons that creak past Pennsylvania chicken farms.
Vaccines are biological products, not chemicals that can be cranked
out in times of need.
The viruses they're made from need cells in which to grow. Yellow
fever and flu are the only vaccines that use eggs for this - not the
kind that come from the store but those produced under strict
pharmaceutical conditions.
Flu also is the only vaccine made fresh every year. In late February
or early March, the World Health Organization picks its three strains
based on the virus going around. If it acts too soon, newly emerging
strains can be missed, as Fujian was last year.
If it waits too long, vaccine makers must race against the biological
clocks of hens, which only lay eggs for nine months until they're too
old, then rush through a several-months-long process to make
enough vaccine before the flu season starts.
"We're constrained on the front end and the back end. No other
vaccine has that kind of time pressure," said Aventis spokesman
Len Lavenda.
Dr. Anthony Fauci, the government's top vaccine scientist,
acknowledged the difficulty.
"The ability to have surge capacity when something goes wrong, to
turn on a dime and try and correct it, is difficult," he said in an
interview Thursday.
Aventis starts making vaccine more than a year in advance, around
August on nearly 50 farms throughout Pennsylvania.
"They're fairly small operations," many with only 10,000 birds, said
Sam Lee, a 40-year-old chemical engineer who is the company's
operations team leader.
White leghorn hens are used. The exact type is a company secret.
The breeder holding the patent supplies the eggs, which take 21
days to hatch and become chicks.
They're moved in late September into buildings where they can
move freely as opposed to cages and coops, and spend three
months maturing into hens.
Egg-laying starts in late December, typically one a day. How many
eggs it takes to make a flu shot is another Aventis secret, but
Chiron's Bryett said: "If you're very lucky, you'll get three doses per
egg." That's for a single flu strain; three strains go into each dose of
vaccine.
The fertilized eggs are collected by two large egg producers, who
incubate them for seven to 12 days and then bring them to Aventis.
Eggs delivered in January would hatch into chicks if not used for
vaccine, so manufacturers often gamble and start making whichever
of the three flu strains WHO seems most likely to choose.
"Any production before February is done at the company's risk," Lee
said.
A machine punches a tiny hole in each shell and a needle inoculates
the chick embryo with a single flu strain. The virus is allowed to
multiply for about three days.
Then the eggs are broken, and the fluid around the embryo
containing the virus is collected and purified. Formaldehyde is
added to inactivate the flu virus, and a machine spins the mixture to
separate out the part containing virus.
Once again, eggs are needed: A sample of the spun solution is put
back in the eggs to see if any virus grows - a test to ensure the
germ was inactivated. A few more processing steps turn it into a lot,
or batch, of several hundred thousand doses of a single strain.
Next comes sterility testing where vaccine is spread onto lab dishes
and checked to see if it contains contaminating bacteria.
"We haven't had a contamination in years," Lee said.
It's not known whether this step is where Chiron's vaccine was
discovered to be tainted with serratia bacteria or if it happened later.
As Aventis tests for sterility, samples also go to the Food and Drug
Administration, which doesn't start its testing until late May or early
June because it has to brew specific chemicals each year to test
specific strains.
After that, three viral strains are combined to form the trivalent
vaccine. Four weeks of potency and sterility testing follow, then
packaging into single-dose syringes and 10-dose vials and quality
checks for potency.
The last doses are made by the end of September. Chicken farms
are free to sell old birds and must do a mandatory cleanout and
disinfection to get ready to start the whole process all over again.
As cumbersome as this egg-based vaccine recipe may seem, "it
has been over the years a reliable, time-tested and reasonably
efficient way to get virus grown," Fauci said.
"Changing that requires genuinely a very, very large investment" to
make a product sold only once a year and for a pittance compared
to expensive cholesterol pills and other drugs that people take every
day, said Dr. William Schaffner, a Vanderbilt University flu expert
who advises the government on vaccines.
"Vaccines in general and flu in particular are undervalued. Prices
are not at the level they should be to attract new investments,"
Aventis' Lavenda agreed.
Aventis has partnered with a company in the Netherlands, Crucell,
to research using human and animal cells in place of eggs. These
so-called cell cultures could be maintained indefinitely and ramped
up on demand whenever vaccine is needed.
It's pricey technology, but cost isn't the only obstacle. Some worry
that the genetic material of these cells might interact with the flu
viruses, creating dangerous hybrids and undercutting the purpose of
the vaccine.
"If it changes the virus, obviously, that would not be desirable,"
Chiron's Bryett said.
Such technology is at least a couple years away, said Fauci, whose
office is funding many such studies.
"There are safety issues, consistency issues," he said. "That's the
reason why you do research on it. If it was just sticking the virus in a
cell culture and go, we would have done it a long time ago."
So we're stuck with eggs for next year and probably several more.
The government has plans in the works to encourage chicken
farmers to maintain year-round flocks so eggs would be available
anytime in case a new single-strain vaccine had to be made to fight
a pandemic.
"Right now we don't have the capacity to reliably create all the
vaccine we would need in that situation," Dr. Julie Gerberding,
director of the federal Centers for Disease Control and Prevention,
said in a news conference earlier this year.
"It is clear that we need to substantially expand our options,"
including looking at whether the vaccine really needs to be updated
every year, Dr. John Treanor, another government vaccine adviser
from the University of Rochester, wrote in a recent New England
Journal of Medicine article.
Public health officials have worried much about bioterrorism, a
threat of unknown proportions. Instead, Treanor writes, the nation
has been caught offguard and threatened by a long familiar foe, "a
virus that predictably - in each and every year - causes major
mortality and morbidity."
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