Influenza Vaccine Advances

Doctor with a blue bandaid that says "Fight Flu" after getting a flu vaccine

What is being done to improve influenza vaccines?

For more than a decade, collaborative efforts in the United States across the federal government and the private sector have led to improved influenza vaccine technologies that have expanded vaccine supply and/or improved vaccine effectiveness.

To further support improvement of influenza vaccines, the White House issued Executive Order (EO) 13887: Modernizing Influenza Vaccines in the United States to Promote National Security and Public Health on September 19, 2019. The EO established a National Influenza Vaccine Task Force, which CDC is a member of, and calls for the modernization of influenza vaccines and vaccine manufacturing along with increased national influenza vaccination.

What are the roles of CDC and the other federal agencies working on flu vaccine improvements?

As the nation’s leading public health agency, CDC is part of a broad inter-agency government effort to improve flu vaccines. One of CDC’s primary roles in this effort is to provide recommendations for the best public health use of existing influenza vaccines. CDC also plays a leading role in conducting year-round global virologic surveillance, supporting the selection and in some cases production of viruses used in influenza vaccines. The agency also supports the development of new and better vaccines. For example, CDC’s Influenza Division is using next generation sequencing and genomic technologies to develop better flu candidate vaccine viruses (CVVs) and more CVVs that represent major and minor genetic subgroups (e.g., clades) and induce an optimal immune response in people. In addition, CDC monitors and reports on the effectiveness of existing influenza vaccines.

Much of the work to improve influenza vaccine technology over the past decade has taken place under the auspices of influenza pandemic preparedness planning, which is led by the U.S. Department of Health and Human Services’ Biomedical Advanced Research and Development Authority (BARDA)BARDA is charged with the development and procurement of medical and non-pharmaceutical countermeasures for pandemic influenza preparedness and response, including flu vaccines. The CDC, the Food and Drug Administration (FDA) and the National Institutes of Health (NIH) are partners in this broad inter-agency government effort. FDA is the federal regulatory agency responsible for assuring the safety, effectiveness, quality, and security of drugs, vaccines and other biological products and medical devices. NIH is the nation’s medical research agency, a role which includes conducting clinical trials for vaccines.

What advances have been made with flu vaccines in recent years?

  • high dose vaccine that is designed specifically for people 65 and older to create a stronger antibody response;
  • flu vaccine made with adjuvant (an ingredient added to vaccine that helps create a stronger immune response in the patient’s body), was approved for people 65 years of age and older;
  • an intradermal vaccine that requires less antigen for an equivalent immune response thus stretching vaccine supply;
  • A U.S.-approved cell-based flu vaccine, which can be made more quickly than traditional egg-based vaccines and does not require a large supply of eggs to produce (learn more from this published article);
    • CDC has established good laboratory practice (GLP) laboratories and procedures to isolate candidate vaccine viruses (CVVs) in qualified manufacturing cell lines that serve as seeds for cell-based vaccine manufacture.
    • CDC performs two-way antigenic testing of cell CVVs that is required for them to serve as a vaccine virus.
  • quadrivalent (four component) flu vaccines that protect against both lineages of influenza B viruses thus offering expanded protection against circulating influenza viruses;
  • the first recombinant influenza vaccines, which can be manufactured more quickly than either egg-based or cell-based vaccines and which does not require an egg-grown vaccine virus nor eggs to produce; and,
  • developing live attenuated influenza vaccines (LAIV): CDC Influenza Division’s Virology, Surveillance, and Diagnostics Branch (VSDB) develops LAIV vaccines that are shared via World Health Organization (WHO) for distribution globally. VSDB recently developed methods to stabilize the vaccine to eliminate the cold chain (learn more from this published article).

What is the long-term goal of efforts to improve the flu vaccine?

One long-term goal is to reduce reliance on egg-based methods of flu vaccine manufacturing and to embrace newer vaccine manufacturing technologies that can be used to more quickly respond to novel flu outbreaks and pandemics. Another long-term goal is the development of a single flu vaccine that would provide safe, effective, and long-lasting immunity (i.e., immunity lasting multiple flu seasons) against a broad spectrum of influenza viruses, both seasonal and novel. A flu vaccine with these qualities is often referred to as a “universal flu vaccine.”

What is CDC currently doing to support development of a universal flu vaccine?

At this time, CDC is participating in a broad inter-agency partnership coordinated by BARDA that supports the advanced development of new and better influenza vaccines. These efforts already have yielded important successes. Part of this effort is the eventual development of a “universal vaccine” that would offer better, broader and longer-lasting protection against seasonal influenza viruses as well as novel influenza viruses. This task poses an enormous scientific and programmatic challenge, but a number of government agencies and private companies already have begun work to advance development of a universal flu vaccine.

Where can I get more information about flu vaccine research?

More information on this topic is available at:

BARDA Strategic Plan, 2011-2016