Flu cases are on the rise across the U.S. as the season gets underway, but vaccinations for the bug aren't always popular. Last flu season, the CDC says  just 41.7 percent of American adults got a flu shot.

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Now the University of Washington School of Medicine is developing a new way to fight the flu, with a vaccine that could offer protection for years.

“I choose not to get the flu shot,” Washington resident Christine Booker said.

Cody Hurde said his 3-year-old toddler is not a fan of the vaccine.

“She hates shots,” Hurde said. “She still cried a bunch, but was braver than last year.”

This year, experts are warning about a severe flu season, and they’re already seeing a rise in flu cases in some parts of the country.

“It’s going to be a particularly bad one,” Dr. Deb Fuller, a professor and researcher with UW Medicine in the Department of Microbiology, said.

Fuller said one reason for the spike in cases compared to last year is this year’s vaccine.

“There’s a bit of a mismatch,” she said. “And a lot of that has to do with the flu, every season it undergoes significant genetic changes,” she said.

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But Fuller is developing a flu shot, called a DNA vaccine, that could change the game.

"It is coming, this is the future of flu vaccines -- to have a universal flu vaccine," Fuller said. "We really believe we can do better than to have to guess every single year what to include in the vaccine and hope it's a good enough match," she said.

The new “universal” vaccine uses genetic material of the influenza virus – the part that doesn't mutate – and teaches your body to recognize it.

“They go like little micro injections into your skin cells,” Fuller explained.

But you won't have to endure a shot or any needles. Her lab developed a "gene gun" that loads up microscopic particles with the DNA into a cartridge, then it uses gas to push out the particles into your skin.

“Then your skin cells are going to start producing flu antigens,” Fuller said.

Fuller is also working on developing a disposable version of the gene gun that would be self-contained and could be widely distributed.

She says the gene gun doesn’t hurt at all, because the particles are too small for your skin to feel.

The DNA vaccine is something Fuller says she's worked on for 12 years.

Her team has already shown monkeys that got the new DNA vaccine were protected even from mutated strains of the flu. Their research was just published last week.

Fuller says it could mean the end of the annual flu shot.

“You get this and you should have immunity for many years against any kind of flu that comes about,” she said.

The new vaccine still needs to go through clinical trials with humans. Fuller hopes it will be on the market in five to 10 years.

Fuller and her team are already testing the technology of DNA vaccines with other diseases, like Zika and HIV.