A University of Pennsylvania study published in the journal Science reports a successful trial of a universal flu vaccine, NewScientist writes. The influenza virus is constantly evolving, so current vaccines are designed to provide immunity against strains that are expected in a particular coming season. However, predictions often do not come true, and vaccination is ineffective. This problem could be solved by a universal vaccine against all strains of influenza. Work has been underway on its development for a long time, but until recently, not a single such vaccine has been approved for widespread use.
Employees at the University of Pennsylvania have created an mRNA vaccine that works by the same mechanism as the Pfizer / BioNTech and Moderna coronavirus vaccines. The new vaccine contains mRNA molecules encoding fragments of proteins found in all 20 known influenza A and B strains that cause seasonal outbreaks each year. In tests on mice, the animals produced antibodies specific to all 20 strains of the influenza virus, and these antibodies remained at a stable level for up to four months.
In fairness, separate experiments have shown that the universal influenza vaccine provides weaker protection against new variants of the 20 influenza strains than the annual vaccine corresponding to new forms of the virus. Nevertheless, the new approach raises hopes for the possibility of developing a universal vaccine.