The heads of multiple health agencies told a House subcommittee Thursday that both the government and industry need to invest more resources in researching new forms of flu vaccines in light of this year’s epidemic.

Vaccines are often developed using egg-based technology, but newer cell-based and recombinant DNA technologies offer more speed and flexibility for fighting viruses — like the flu — that mutate frequently. While the technology offers promise, it remains uncommon, with lingering gaps in technology.

Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases within the National Institutes of Health, highlighted the “underlying inertia” in private industry that stops it from moving away from “antiquated” technology.

“The thing that I think that we need to emphasize is that we’ve got to go there,” he told the House Energy and Commerce Oversight and Investigations Subcommittee. “We can’t stay stuck in the old technologies.”

The flu hit the public especially hard this year, resulting in a higher mortality rate and at least 114 children’s deaths. But just 18 percent of vaccines are cell-based this season, and only 3 percent are produced with recombinant DNA. The H3N2 strain of the virus — which vaccines are typically less effective against — is to blame for much of the outbreak.

The problem, according to Fauci, rests with a particularly complex mushroom-shaped protein in the flu virus. The head of the protein mutates frequently, while the makeup of the stem remains relatively constant. Researchers are working to develop a universal vaccine that homes in on the stem to improve efficacy across the flu’s various strains.

This flu season, the vaccine is estimated to be just 36 percent effective against all strains of the illness and 25 percent against the H3N2 strain, although that rate varied among demographic groups. The immunization is 51 percent effective against the H3N2 strain in children ages six months to 8 years old, and just 17 percent effective in seniors ages 65 and older.

But egg-developed vaccines remain relatively safe and effective overall, so drugmakers are uninterested in making the leap to newer methods, according to Rick Bright, director of the Biomedical Advanced Research and Development Authority, or BARDA, which works with drugmakers to develop new vaccines.

The marketplace is not conducive to the development of new antiviral medications, either, Bright said. The Food and Drug Administration has not approved a new class of antivirals in the last 20 years.

“The virus, as we know, continues to change, and resistance to that class of antivirals continues to emerge,” he said, calling the trend “very concerning.”

BARDA is working with several companies to address the flu. One potential solution is Japanese company Shionogi’s pill Xofluza, which can kill the flu in a single day. The medication targets the virus in an earlier stage of its replication.

“The bottom-line message is that we are very interested in having a spectrum of antiviral drugs that act differently at different points in the virus in case the virus itself becomes resistant to one approach targeting the virus,” FDA Commissioner Scott Gottlieb said.

President Donald Trump requested $250 million from Congress to fight the flu in 2019. The Pandemic and All Hazards Preparedness Act, which created BARDA, is set to expire in September.

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