Scientists from across the country and the globe are making progress toward developing a universal flu vaccine, but reaching that goal will likely still take years, a top administration health official said Wednesday.

The National Institutes of Health recently funded a phase two clinical trial of what is one of several likely candidates for a universal influenza vaccine, said Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases, which is part of the NIH. The first version of a vaccine that might protect against any type of flu likely won’t actually be universal but more targeted to specific strains, though, Fauci said.

“It’s not going to be next year or the year after because it’s going to be an iterative process,” said Fauci, who spoke Wednesday at the National Press Club.

His comments come on the heels of a particularly brutal flu season, especially for children.

In June, the Centers for Disease Control and Prevention reported 172 flu-related deaths of children for the 2017-2018 season — one of the deadliest years on record, excluding pandemic periods. Roughly 80 percent of those who died had not received a seasonal flu vaccination, according to the agency.

Current vaccines help protect against particular strains of flu predicted to spread in a given year. Flu strains typically mutate at least slightly from one season to the next, creating the need for new vaccines every year.

The effectiveness of yearly vaccines can range from 10 percent to 60 percent, Fauci said. The goal in a universal vaccine would be to target parts of the virus that don’t change from season to season, he said.

A universal vaccine will likely develop in stages with one version targeting a particular flu strain, such as H3N2, and then building on that to protect against another, such as H1N1, and so on, he said. Ultimately, researchers hope to develop a vaccine that could be given to children as young as six months and protect them for years, though there may be a need for occasional booster shots, he said.

Efforts to develop a universal flu vaccine received a lift from Congress earlier this year in the March omnibus package, which included $100 million in NIH funding for such research in fiscal 2018, compared with $64 million in 2017. In a May letter to the Trump administration, a group of a half dozen Democratic senators, as well as one independent, also urged support for a separate measure that would authorize an additional $1 billion for universal flu vaccine research over five years.

“Despite the damage inflicted by influenza annually, our current vaccine is only 60 percent effective at best,” the senators wrote. “It is critical that we develop a more effective and longer lasting approach to preventing influenza.”

Fauci pointed out that NIH funding remained flat for more than a decade before increases from Congress in the last two years.

Public health experts hope greater investment will continue.

“Congress is going to have to continue to make investments in research so that we stay ahead of the curve,” said Georges Benjamin, executive director of the nonprofit American Public Health Association, which focuses on federal public health policy. “These fits and starts in terms of investments is a bad idea.”

Such funding not only advances science and innovation but creates jobs and boosts the economy, too, Benjamin said.

Achieving a universal flu vaccine would also not only reduce the risk of illness and death for Americans but also free up money and manpower to help address other types of preventable diseases, he said. Benjamin added that he hopes someday scientists will achieve the same level of advancements for flu vaccines as those reached in other areas of medicine, such as treating certain cancers.

“We’ve got a ways to go,” he said. “It’s going to take a lot more research, a lot more investment, but it’s worth it in the end.”

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