H1N1 Swine Flu Vaccine Delayed
45 Million Doses Will Be Ready by Tentative
Oct. 15 Start Date
By Daniel J. DeNoon
WebMD Health News
Reviewed by Louise Chang, MD
Aug. 20, 2009 - By November, the U.S. will have only
half the doses of H1N1 swine flu vaccine originally predicted, officials from the Department of Health
and Human Services now say.
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By Oct. 15, the U.S. now expects to have 45 million doses of the new vaccine
on hand. Every week after that, another 20 million doses should roll in until
the nation has all 195 million doses it's contracted for from five vaccine
This means that at the end of October, there should be 85 million doses --
just over half the 160 million doses predicted by that date.
There was always an asterisk next to the prediction of
160 million swine flu
doses by November. That's because vaccine production is a multi-step process in
which a lot can go wrong.
Officials originally felt smug when it turned out that the original H1N1
swine flu vaccine seed strains didn't grow well -- that was included in their
But there have been new setbacks:
- Four of the five manufacturers providing the vaccine
to the U.S. took longer than expected to produce the vaccine's key ingredient.
- One of the five manufacturers is still finishing up
production of seasonal flu vaccine, which must be completed before switching
to H1N1 swine flu vaccine production.
- It's taken longer than expected to develop potency
tests for H1N1 swine flu vaccine.
- One of the manufacturers -- Australia's CSL, under contract to provide
19% of the U.S. supply -- won't be sending vaccine to the U.S. until it has
fulfilled demand in Australia, where
flu season is in full swing.
There's good news from MedImmune, which makes the live attenuated flu vaccine
called FluMist. Production is ahead of schedule on the H1N1 version of this
vaccine, which is administered by nasal inhaler. The snag here is that there
aren't enough inhalers for all the new doses. The FDA must give the nod to
giving the vaccine in the nose-drop form tested in early clinical trials.
By the end of the year, the U.S. will have all 195 million H1N1 swine flu
doses it originally ordered. Whether that's enough, or too much, depends on
Right now, the U.S. is bracing for a resurgence of the pandemic. The new flu
strikes young people most often, and schools and universities across the nation
are opening. All flu bugs like cool dry air -- and fall weather is on the way.
If, as expected, there's a new wave of H1N1 swine flu -- and if it doesn't
peak before the vaccine becomes widely available -- demand for the vaccine will
be high (as it now is in Australia). But interest may wane if the next wave of
the flu pandemic peaks before most people can get the vaccine.
It seems likely that people will need two doses, given three weeks apart, for
protection. That means even those at the front of the vaccine-priority line
won't be fully protected until late November, four to six weeks after their
Ongoing clinical trials will soon answer the question of
whether one or two doses is needed, and whether the vaccine appears as safe a
the seasonal flu vaccines on which it's based.
Meanwhile, states are making plans for widespread vaccination against both
seasonal and pandemic flu.
Department of Health and Human Services.
CDC web site.
WebMD Health News: "Swine Flu Vaccine: When?"
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