What’s the plan? The U.S. CDC is being asked that question a lot these days – not just about COVID-19, but also about preparing for what could be a tough influenza season as flu bugs circulate with the coronavirus.

With little known about the interaction between influenza strains and SARS-CoV-2 or the severity of co-infection, public health and infectious disease experts are warning that the U.S. “needs to increase its influenza vaccination rate substantially this fall to mitigate a potentially deadly confluence of seasonal influenza [and] an anticipated second wave of COVID-19,” Republican leaders of the House Energy and Commerce Committee said in a Sept. 14 letter to CDC Director Robert Redfield.

If predictions of up to 100 million cases of influenza-like symptoms prove true for the coming flu season, the current testing capacity for influenza would be overwhelmed, according to the letter, signed by Ranking Member Greg Walden (R-Ore.) and Reps. Brett Guthrie (R-Ky.) and Mike Burgess (R-Texas), the ranking members of Energy and Commerce subcommittees dealing with health and oversight issues. And if COVID-19 and influenza outbreaks overlap and peak around the same time, the stress on hospitals and supplies would intensify, the lawmakers said as they once again asked the CDC, “What’s the plan?”

The letter noted that the government and private sector have ramped up the production of influenza vaccines to record levels. Manufacturers have projected that they will provide as many as 198 million doses of influenza vaccine for the 2020-2021 flu season. That would be 13% higher than the record 175 million doses produced last year, according to the lawmakers. Meanwhile, the CDC, which usually purchases about 500,000 doses of influenza vaccine for adults per season, this year has purchased 9.3 million doses – plus an additional 2 million doses of pediatric influenza vaccine.

Along with those purchases, which will be distributed to the states, the CDC is working on an education campaign targeting the most vulnerable populations to urge them to get a flu shot. But all the preparedness is no guarantee Americans will heed the warnings.

Vaccination rates

For years, an annual flu vaccination has been recommended for all people age 6 months and older, but over the past decade, influenza vaccination rates for adults in the U.S. have ranged between 40% and 45% – well below the government’s 70% target. The numbers are worse for adults in minority communities.

While 49% of white and 44% of Asian adults in the U.S. got flu shots in the 2018-2019 flu season, the vaccine rate was 39% for Black adults, 38% for American Indian or Alaska Native adults, and 37% for Hispanic adults, according to a Sept. 15 report from the Kaiser Family Foundation.

Influenza vaccination rates for children have been higher across the board due to programs such as the federally funded Vaccines for Children, but they still are under the 70% target in most groups. The Kaiser report found that 71% of Asian children, 66% of Hispanic children, 61% of white children, 60% of Black children and 59% of American Indian or Alaska Native children received influenza vaccines in the 2018-2019 season.

Safeguards to protect against COVID-19 could impact influenza vaccine rates this year. In the past, many adults got their vaccines at their workplace. Now, a lot of those people are teleworking, so workplace vaccine programs won’t be as available, Walden, Guthrie and Burgess said in their letter. They encouraged the CDC to consider creative outreach venues, such as mobile vaccine units or drive-thru stations, to ensure influenza shots are widely accessible.

Another concern the lawmakers raised has to do with testing and the demands it could place on an already constricted reagent supply. They urged the CDC to increase access and availability to its technology that can simultaneously test for COVID-19 and seasonal influenza strains.

The letter cited a CDC email the lawmakers received last month in which the agency acknowledged that testing for the coronavirus and influenza strains simultaneously in a single test reaction would save time and resources and would potentially help mitigate supply shortages should testing volumes increase substantially. The CDC said it expected its influenza SARS-CoV-2 multiplex assay, which received an emergency use authorization (EUA) in July, would improve throughput at least threefold compared with using its current single-plex SARS-CoV-2 assay. The multiplex test also will find co-infections of influenza and COVID-19, which will help doctors better diagnose and treat patients.

As of mid-August, the CDC had shipped 135 multiplex assays, each containing about 500 tests, to 101 laboratories across the U.S. To make the tests more broadly available, the agency has made its technical information available to commercial developers and has granted them right of reference to its EUA. In their letter, Walden, Guthrie and Burgess asked the CDC for a briefing on the status of those efforts.