WASHINGTON - Flu season's in full swing two months early this year - and nearly all the cases are the new swine flu strain that so far is targeting mostly children and younger adults.
That doesn't mean older people are off the hook. They sometimes catch swine flu. Also, we could see a one-two punch when regular flu strains start circulating as the weather gets colder. You probably won't know which kind you have. Very few people will get the specialized testing to tell. That doesn't matter - treatment's the same for both.
Here are answers to some questions about what the Centers for Disease Control and Prevention predicts will be a busy and long flu season.
Q: Where's the vaccine, and how many shots will I need?
A: Many people will need to line up twice. One vaccine protects against regular winter flu, and that vaccine's available now. A separate vaccine to protect against swine flu - the 2009 H1N1 strain - will arrive in October. It appears that adults will need one dose of that vaccine; dose studies are under way in children to see if they'll need a booster.
Q: Why couldn't both kinds be put into one shot?
A: Bad timing. Swine flu didn't burst onto the scene until April, after manufacturers had already begun brewing this fall's regular flu vaccine and too late to add into that mix.
Q: How does swine flu compare to regular flu strains?
A: So far it doesn't seem any more deadly than regular flu, which kills 36,000 Americans a year and hospitalizes 200,000. But swine flu does sicken the young much more frequently than the old, and it spreads very easily, especially in crowded schools. A University of Washington study found the typical sick school student infects two to three classmates - so keep sick kids at home.
The sad reality: You can be contagious up to 24 hours before you show symptoms, one reason flu spreads so easily.
Q: Who's at highest risk of severe illness or even death?
A: Children under 5. Pregnant women. People 65 or older. And people of any age with asthma or other lung disorders; diabetes; heart, kidney, liver or blood disorders; neurodevelopmental disorders such as cerebral palsy; or a weakened immune system.
Q: I think I had swine flu over the summer. Do I still need the vaccine?
A: Yes, says CDC flu specialist Dr. Anne Schuchat. Other viruses mimic flu so it's hard to be sure what you had.
Q: How does swine flu affect children, and what symptoms should prompt a race to the pediatrician?
A: Symptoms are the same regardless of age: Fever, aches, cough, sore throat, sneezing or runny nose, sometimes diarrhea and vomiting.
The CDC says to seek immediate care if a child has difficulty breathing or is breathing fast, turns bluish, isn't drinking enough fluids, has severe vomiting, is hard to wake up or lethargic, or is so irritable the child doesn't want to be held.
Also seek care if the fever breaks and then later returns, sign of a possible bacterial infection.
Q: What are emergency signs for an adult?
A: Difficulty breathing, pain or pressure in the chest or abdomen, dizziness, confusion, severe vomiting or a rebound fever.
Q: Won't I or my child need those anti-flu medicines, Tamiflu or Relenza?
A: No, most won't, stresses CDC's Schuchat. Most people will recover with rest and fluids - don't get dehydrated.
But people at high risk should make a plan with their doctor now, before they're sick, Schuchat advises. They may need Tamiflu within the first 48 hours of symptoms, and some doctors may agree to an advance prescription if they promise to call with symptoms - saving time and exposing others in the waiting room.
Q: How long should sick kids stay out of school or day care?
A: For 24 hours after the fever breaks naturally, not because of fever-reducing medicine. And never give a child aspirin, only non-aspirin fever reducers. For a child under 5, ask a doctor first about type and dose.
You're considered more contagious while feverish. But children especially can be contagious for over a week, so doctors say use common sense - stay home if you're still sick after the fever breaks.
Q: Is it true that not everyone gets a fever?
A: Yes. There are no good estimates although the CDC thinks it's not too common.
Q: Someone's sick in my office. How long until I know if I caught it?
A: Up to a week.
Q: Do I have an obligation to notify my friends or employer if I or my child get sick?
A: "Of course you tell your friends," especially if you've been around someone who's at high risk, says Dr. William Schaffner of Vanderbilt University. Treat flu like any other easy-to-spread illness. Families normally tell the school and playmates when a child gets strep throat, for example. Employers must weigh privacy requirements but certainly can advise that flu has hit the office.
Q: But what if I hate shots?
A: There's FluMist, the squirt-in-your nose vaccine, available for people ages 2 to 49.
Q: What if I have asthma?
A: Any flu can worsen asthma attacks, warns CDC asthma specialist Dr. David Callahan. Children may be prescribed Tamiflu at the first symptoms, so call your doctor. Keep a good supply of regular asthma medicines, including "rescue" inhalers for asthma attacks, on hand.
Q: What if I have diabetes?
A: Flu can increase a diabetic's blood sugar, so test frequently and call your doctor about adjusting insulin or other medications, said CDC diabetes specialist Dr. Ann Albright. Keep a two-week supply of regular medication. Stay hydrated. And check your ketone levels.
Q: Can you catch flu from the flu shot? You hear people say," I was sick the day after the shot!"
A: No, it's biologically impossible for a flu shot to give you influenza; it's made with a dead virus. But the flu shot won't prevent a cold or other flu-like viruses, causing some confusion.
Q: My child was told to bring hand sanitizer to school and use it regularly. Is there any concern with that?
A: Nope, says the CDC. It shouldn't be more drying to skin than soap. Just keep the whole bottle away from toddlers who might try to swallow it.
Q: Why isn't everybody tested?
A: Rapid tests just tell if you have flu, not which strain, and aren't always accurate. More sophisticated testing takes too long to be practical. The CDC does enough testing to tell what strains are circulating where but for the average person it doesn't matter - flu's flu.
• Lauran Neergaard covers health and medical issues for The Associated Press in Washington.
Flu information: http://www.flu.gov