Last winter’s dreadful flu season may have had a silver lining: Flu vaccine uptake rose sharply this fall in both children and adults, according to newly released data.

The Centers for Disease Control and Prevention reported Friday that the number of children and teens vaccinated as of mid-November was up nearly 7 percentage points over last year at that time and coverage among adults was up 6.4 percentage points.

The data, which were drawn from three CDC-sponsored surveys, do not indicate whether more people will be vaccinated overall this winter — or that last year’s flu season is changing behavior this winter. The increase could mean that more people were inspired to get their flu shot sooner this year.

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“It’s a good sign, but it’s too early to interpret,” said Michael Osterholm, director of the University of Minnesota’s Center for Infectious Diseases Research and Policy.

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The increase in early vaccinations may be due to fresh memories of last winter. But Osterholm said other factors could also be at play.

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“I don’t know if that’s what did it or if in fact there are more organized programs to get people vaccinated,” he said.

The CDC acknowledges that it’s hard to say for sure what is driving the increase, but it’s working theory is that more people are getting vaccinated because last winter reminded them that influenza can be dangerous.

Last year’s flu season was one for the ages, with high-level activity stretching over several months. The CDC estimated that 80,000 Americans in total were killed by the flu; 185 children died. Last season’s flu activity was caused mainly by the influenza A virus H3N2, which is associated with more severe flu seasons.

Dr. Ram Koppaka, associate director for adult and influenza immunization, in the CDC’s immunization services division, noted that there was a rise in vaccination rates after the 2009 flu pandemic that was sustained over a number of seasons.

The rate hovered around 46 percent or 47 percent for several years, but dropped back to 42 percent last year.

Fewer than half of Americans have been vaccinated overall this year — 45.6 percent of children and 44.9 percent of adults had received flu vaccine.

Still, more young children are getting vaccinated this year over last year. There was an 8.2 percentage point increase in uptake among children aged 6 months (the earliest flu vaccine can be given) and 4 years and a 7 percentage point increase among children aged 5 to 12 years old.

But teens aged 13 to 17 were vaccinated at the same rates as last year, with only about 35 percent of children in this age group vaccinated.

The CDC report noted that experience from previous flu seasons shows that people continue to get vaccinated through the winter and even into spring, with end-of-season rates in children 19 percentage points higher than the early season rates, and 8 percentage points higher in adults.

Flu activity so far this season remains low, though there are signs that it is picking up steam. Six child flu deaths have been reported to the CDC.