Brazil defines composition of flu shots for 2023
Brazil’s drug regulator Anvisa today (Oct. 26) approved the composition of trivalent and quadrivalent shots against influenza to be administered in the country in 2023.
For next year, the doses produced from chicken eggs must utilize strains Influenza A/Sydney/5/2021 (H1N1) pdm09, Influenza A/Darwin/9/2021 (H3N2), and Influenza B/Austria/1359417/2021 (B/Victoria).
In non-egg-based vaccines, the A (H3N2) virus strain should be a virus similar to the Influenza A/Darwin/9/2021 (H3N2) virus, along with the other A (H1N1) and B strains.
The quadrivalent vaccines, which include two types of Influenza B virus strains, should contain a virus similar to the Influenza B/Phuket/3073/2013 virus (B/Yamagata), in addition to the three types of strains mandatory for trivalent doses.
After the publication of the composition by the watchdog, the pharmaceutical companies with registration rights must adjust their products for the manufacture of supplies for 2023.
How it works
Every year, the World Health Organization examines all flu sub-types circulating worldwide and decides which are the most intense, so that the efficiency of the doses can be improved.
“The change in the composition of strains in influenza vaccines is vital for the efficiency of the inoculation, as viruses adapt and mutate,” Anvisa stated.
