Although no one knows yet how severe this flu season will be, now is the time to get vaccinated, health officials say.
Already this season, a 4-year-old from California who recently died tested positive for influenza, local health officials reported earlier this month. The child did have underlying health conditions, they added.
"Flu is incredibly unpredictable," said Lynnette Brammer, leader of the domestic influenza surveillance team at the U.S. Centers for Disease Control and Prevention.
Last year was a perfect example of that. "We saw something we had never seen before," she said. "We saw two waves of influenza."
Both waves included the influenza A strain H3N2, which is a particularly severe type of flu. The first wave was well matched to the vaccine, but the second wave saw a changed H3N2, for which the vaccine was less effective, Brammer said.
This year's vaccine has been tweaked to account for the changes in the H3N2 virus, and the influenza A strain H1N1 has also been updated, she said.
As far as B flu strains are concerned, this year's vaccine is like last year's because these viruses haven't changed. "It looks like we're ready for this season," Brammer said.
"Vaccination is our best tool against flu, and now's the time to start getting vaccinated," she said.
People need to get vaccinated each year, not only because the vaccine has changed, but because your immunity wears off, she explained.
The CDC recommends that everyone aged 6 months and older get a flu shot.
Brammer said that some people think the vaccine isn't very effective, so they skip getting it. Even if the vaccine isn't as effective as the CDC would like, it still protects millions from getting the flu.
Also, even if you get sick, the vaccine makes your illness less severe. "Vaccine effectiveness isn't always what we would like, but flu vaccine can reduce your risk of hospitalization 40%, and for healthy kids, it can reduce their chance of dying by 65%," she noted.
For this year's flu season, somewhere between 162 million and 169 million doses of flu vaccine will be available, Brammer said.
For kids and some adults who don't like shots, a nasal spray vaccine is available.
It's particularly important for people who have chronic heart or breathing conditions to get vaccinated because flu can make these conditions worse.
Pregnant women should also get their shot to protect themselves and their baby, the CDC recommends.
If you do get the flu, antiviral medications are available that work against the viruses currently circulating.
The trick is to see your doctor as soon as you get sick because these drugs work better the earlier you take them. "Antiviral medications can help you get better quicker," Brammer said.
The bottom line is get vaccinated now - because you don't know what this flu season will bring, she advised.