(AP) -- Flu season's arrived with lots of coughing and fever in the South and New York City, and it's sure to spread to the rest of the country. The good news: There's still plenty of vaccine for procrastinators.
But don't wait much longer - it takes about two weeks for the vaccine's protection to kick in.
"Take the opportunity while you've got the chance," advises Dr. Daniel Jernigan of the Centers for Disease Control and Prevention.
If this seems like a late start for influenza, not so: We're just getting back to normal after the swine flu pandemic that made the 2009-10 flu season hit unusually early.
January and February typically are the worst flu months, and it can drag into March. And this winter, a well-known nasty strain of Type A flu is causing most of the illnesses so far in the U.S. This so-called H3N2 branch of the flu family tends to trigger more pneumonia and other complications than other forms of influenza.
It's a different story overseas, where swine flu has returned to hit Britain hard and vaccine again is running low there. European health authorities warned the bug was sure to reach the continent next and urged a last-minute effort at boosting vaccinations in countries like France and Germany where protection historically is low.
This year's vaccine does offer triple protection - against the swine flu known formally as Type A H1N1 flu, the worrisome H3N2 strain, and the Type B flu that tends to be less severe.
And the U.S. produced more than 160 million doses this year, a record amount. Last year, nearly 114 million doses of seasonal vaccine were used, but lots of the special swine flu vaccine went to waste because it didn't arrive until that outbreak was waning and people had lost interest.
The challenge is getting more people to use this plentiful supply in a year that so far hasn't made much news about illness that can drive vaccination, says Dr. Jonathan Temte of the University of Wisconsin and the American Academy of Family Physicians. He pushes his own patients to be vaccinated, and this year had so many shot-haters flock to the nasal-spray FluMist version that he had to order a second batch.
Dr. Sarah Nafziger is caring for "a ton" of flu patients in the emergency room at the University of Alabama Birmingham - and she makes a point of asking why they didn't avoid the misery by getting vaccinated, in hopes they'll remember the lesson.
"Most of the time they don't show a lot of remorse," she says, surprised.
The CDC says the flu so far is striking very hard in parts of the South - Alabama, Georgia, Louisiana and Mississippi - and New York City. Illinois and Oklahoma also are reporting high levels of flu. It's what Jernigan calls expected levels for the leading edge of the winter's outbreak - and that latest count is for the last week of December, the holiday lull when lots of people are home from school and work and thus not trading germs as widely as usual.
Enough Americans either caught swine flu or were vaccinated against it during the last flu season that it's having a difficult time returning here this year, Jernigan says, but a smaller proportion of Britain's population entered this winter similarly protected. Here, the predominant H3N2 strain tends to be especially hard on the very young and very old, he warns.
There's also a fair amount of Type B flu circulating. In his health clinic, UAB physician Dr. Stephen Russell is seeing lots of those people who have cough and fatigue lingering for 10 days instead of the usual three or four with that strain.
People tend to think January's too late to get vaccinated when it's not, says Dr. Jane Zucker, a New York City assistant health commissioner whose office is running TV ads to spread that message.
There's no good count yet of how much vaccine the country's used, but it's clear that a lot is still available. Often, it's at retail pharmacies that tend to charge $20 to $30, although they will file with a customer's insurance.
Drugstore giant Walgreens aims to give 15 million flu shots this year and has given nearly 6 million so far, making it the single largest non-government provider of flu vaccine. Federal health officials announced last month that the company agreed to donate $10 million in vouchers for enough free shots for 350,000 uninsured people in regions deemed especially in need.
Grocery giant Kroger won't say how many shots it's given, but has dropped the price from its original $24.99 to $19.99, or in some locations $14.99. It, too, is distributing free-shot vouchers in areas the stores serve, through the Salvation Army and another charity, Feeding America.
The CDC recommends vaccine for most everyone except infants younger than 6 months and people with severe allergies to the eggs used to brew it.
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