Like the World Health Organization previously, the Academy of Medicine is calling for the use of so-called trivalent vaccines against seasonal influenza, following changes in the circulation of virus strains.
- In February, the World Health Organization recommended abandoning quadrivalent seasonal flu vaccines because one strain of the virus is no longer circulating.
- In France, the Academy of Medicine supports this recommendation.
- The B/Yamagata lineage of the virus should therefore disappear from the formula.
The flu virus evolves, the vaccine must change too. In a communicated dated May 15, the Academy of Medicine calls for changing the composition of influenza vaccines and returning to so-called trivalent vaccines. This announcement follows a communication from the World Health Organization last February.
Seasonal flu vaccination: why should we change the formula?
“The most commonly used influenza vaccines are inactivated influenza vaccines administered by intramuscular injectionnoted WHO. They are of the trivalent (three strains) and quadrivalent (four strains) type.” But she recalls that the composition of these vaccines must be updated, because “Influenza viruses are constantly evolving.. In his last notice, she therefore advises using vaccines prepared with three strains: H1N1, H3N2 and Lineage B/Victoria. On the other hand, it recommends abandoning so-called quadrivalent vaccines containing the so-called B/Yamagata lineage strain. “No detection of B/Yamagata lineage virus has been confirmed since March 2020warns the organization. Following the WHO recommendation of September 2023, the WHO advisory committee on the composition of influenza vaccines considers that the B/Yamagata lineage should be excluded from influenza vaccines.”
Seasonal flu: the Academy of Medicine also calls for a return to the trivalent vaccine
In his recent communicated, the Academy of Medicine agrees with this recommendation. “In order not to deprive the most vulnerable people of enhanced protection against influenza, the National Academy of Medicine suggests that the return to trivalent vaccines be used to produce a trivalent HD formulation, the effectiveness of which will be monitored must be implemented and the fair price must be determined and that this return to trivalent vaccines is implemented, in accordance with the WHO recommendation, if possible from the next vaccination campaign in the northern hemisphere”, indicates the document. HAS BFMTVBruno Lina, professor of virology at Lyon University Hospital, explains that this request for reformulation is not “a flashback”. “We adapt the composition of vaccines to the circulation of viruses to meet the needs as closely as possible.“, he explains.
Could a new flu vaccine be available for the next vaccination campaign?
On the other hand, this could take time. Before being placed on the market, a vaccine must be validated by the European Medicines Agency and the National Medicines Safety Agency (ANSM). According to BFMTVit is unlikely that the new formulation will be available as early as October.
