(AP) -- Get ready to roll up your sleeve three times for flu shots this fall. That's right, three times. This year's flu season is shaping up to be a very different one. Most people will need one shot for the regular seasonal flu and probably two others to protect against the new swine flu.
Experts suggest you get that first shot as early as this month - if you can find it.
"We'd like to get to Job 1 and get most of it done," said Dr. William Schaffner, a Vanderbilt University flu expert, referring to seasonal flu vaccinations.
"Get it done before we start to tackle Job 2," the more complex task of swine flu vaccinations, he added.
The five vaccine manufacturers that supply the United States are finishing up production of seasonal flu vaccine earlier than usual. Health officials say they expect about half of the more than 120 million doses of seasonal vaccine to be available by the end of this month. Most of the rest are due out by the end of September. Some manufacturers report that distributors are quickly buying up supplies.
Those five companies - including one that makes a nasal spray version of flu vaccine - are the same ones making the new swine flu vaccine. They are on track to start delivering the first batches of that in September, but the bulk of it isn't expected until late October or November, health officials say.
That's sparked questions about how all this is going to work.
Officials want to get as many people as possible vaccinated against both forms of flu, but a lot of that depends on consumers and how many trips they'll be willing to make to get shots.
Why can't you get one shot for all - or maybe just two?
The reasons have to do with logistics and caution.
Scientists believe the swine flu vaccine will be most effective if given in two doses, about three weeks apart. Also, they don't think the seasonal and swine flu vaccines can be combined into one syringe or vial and still be effective, so they've got to be administered as separate doses, even if it's during the same appointment.
But it's not a matter of just giving both to whoever comes in. Supplies are expected to be limited, so the federal Centers for Disease Control and Prevention has two different lists for who should be first to get the seasonal flu shot and who should be first to get the swine flu shot.
For the regular flu vaccine, elderly people, health care workers and pregnant women are among the priority groups. For the swine flu vaccine, health care workers and pregnant women are on the list but not older people, who seem to have some immunity to swine flu.
If all the flu shots were given at about the same time, it could mean a mash of people, some of whom should be among the first to get one shot and not the other.
"I think it's safe to say we expect some confusion," said Kristine Sheedy, a CDC communications specialist.
Then, there are safety questions.
Health officials are haunted by the swine flu vaccine campaign in 1976, which was stopped after unexpectedly high numbers of patients suffered a paralyzing condition called Guillain-Barre Syndrome. While it's not clear the vaccine was to blame, health officials want to carefully monitor people who get the new swine flu vaccine for any problems.
Scientists are just beginning to test the safety and effectiveness of the new swine flu vaccine, work that is expected to take months. If the seasonal flu and swine flu vaccines were given at the same sitting and some people developed health problems, it would be hard to single out which vaccine caused the problem, or whether it was the combination of them.
"How you're going to separate that out - that's a doozer," said Dr. Samuel Katz, a Duke University vaccines expert, who was a developer of the measles vaccine.
So the government is looking at three shots, preferably over three visits.
That's daunting. Over the years, the public hasn't been great about getting even one flu shot: Just one in three U.S. adults got flu shots last year, CDC data indicate.
"To come two or three times? That's expecting a lot, of public response," said Katz.
Health officials traditionally kick off an autumn vaccine campaign against seasonal flu in late September or October with a news conference in Washington D.C. But this year, the news conference - which features the CDC director - has been moved up to Sept. 10.
Unofficially, the push for seasonal vaccinations begins even sooner, some health officials said.
"As soon as it becomes available, we'll be encouraging people to get it," said Carol Schriber, a spokeswoman for the North Carolina Department of Health and Human Services.
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