GAO-25-108286 Universal Vaccines
Science, Technology Assessment,
and Analytics
SCIENCE & TECH SPOTLIGHT:
-25-108286, May 2025
WHY THIS MATTERS
Existing vaccines for diseases such as flu and coronaviruses
require frequent updating. In contrast, universal vaccines
could provide long-lasting protection against many or all
strains of a specific virus. Although they are in the early
stages of development, these vaccines could someday
improve public health and reduce vaccination frequency.
KEY TAKEAWAYS
» Universal vaccines could provide long-lasting, broad
protection against specific viruses and reduce the impact
of outbreaks.
» Multiple candidates for universal vaccines have reached
clinical trials, including flu vaccines.
» Further research on the potential effectiveness of
universal vaccines could inform decisions on whether to
further invest in this technology.
THE TECHNOLOGY
What is it? Compared to existing vaccines, universal vaccines
have the potential to provide longer-lasting protection against
current and emerging virus strands, including those with the
potential to cause pandemics. While traditional vaccines are
generally effective against specific strains of a virus, they lose
effectiveness because viruses change over time, which is known
as mutation. In contrast, universal vaccines could offer
protection against future strains of rapidly mutating pathogens
like flu and coronaviruses.
How does it work? Universal vaccines are designed to train the
immune system to recognize and target virus structures that are
consistent across many or all strains of a given virus. For
example, scientists are developing a universal flu vaccine that
targets the part of the protein the virus uses to enter human
cells. This part of the protein remains largely unchanged as the
flu virus mutates. By stimulating an immune response to these
stable elements, universal vaccines could provide broader and
longer-lasting protection than traditional vaccines.
How mature is it? Researchers have made significant progress
in understanding how universal vaccines could work. Advances
in vaccine technology have improved the feasibility of universal
vaccines. For example, scientists can now fuse together
microscopic pieces of many different virus strains, increasing the
number of strains that can be targeted in a single dose.
Since 2015, most clinical work on universal vaccines has
focused on the flu, which mutates rapidly. Federal agencies
have also invested in universal vaccine research. For example,
the Department of Defense and National Institutes of Health
(NIH) have funded research on developing a universal flu
vaccine. In May 2025, the Department of Health and Human
Services and NIH announced the development of a “next-
generation, universal vaccine platform,” with trials for flu
vaccines scheduled to begin in 2026. Another example of recent
work focused on universal vaccines to protect against any
mosquito-borne disease.
Multiple universal vaccine candidates targeting the flu and other
viruses have reached clinical trials. Between January 2015 and
April 2025, researchers began or completed eight early clinical
trials of universal vaccines, according to ClinicalTrials.gov, but
none have reached the market yet. It may take years for trials to
yield a successful candidate and for the Food and Drug
Administration to license a universal vaccine to be marketed in
the U.S.
OPPORTUNITIES
Universal vaccines could extend immunity against diseases and
reduce the need to update vaccines as frequently. For example:
