Coronavirus “exterminated” a flu strain: Trivalent and not quadruple time vaccine

Its new recommendations for influenza virus strains to be included in the treatment to be administered from the autumn of 2024 today (26.03.2024), the European Medicines Agency (EMA). According to the recommendations of the EMA Emergency Group (ETF), the flu vaccine will now be trivalent (and not quadruple), as it will no longer target the Yamagata series of influenza B virus. Currently, most approved flu vaccines are quadrupulous, meaning they are designed to protect against the four main strains of flu responsible for seasonal influenza, A(H1N1)pdm09 and A(H3N2), B/Victoria and B/Yamagata. However, the B/Yamagata strain of influenza B virus has been detected since March 2020. It is estimated that this is partly due to measures to protect public health taken to limit the spread of coronavirus and Covid-19’s disease during the pandemic. Influenza B viruses are responsible for 25% of flu cases recorded annually. Since the B-Yamagata strain no longer appears to pose a threat to public health, it is not necessary to include it in the synthesis of influenza vaccines. Manufacturers of live attenuated vaccines or trivalent egg-based vaccines should include these three strains of virus for the period 2024 – 2025 : A/Victoria/4897/2022 (H1N1)pdm09. A/Thailand/8/2022 (H3N2) virus. B/Austria/1359417/2021 (B/Victoria line). Cell-based trivalent vaccine manufacturers should include these three strains of the virus for the period 20242025: A/Wisconsin/67/2022 (H1N1)pdm09-like virus. A/Massachusetts/18/2022 (H3N2)-like virus. B/Austria/1359417/2021 (B/Victoria line). Manufacturers of inactivated vaccines may consider producing a tetravalent vaccine containing two strains of influenza B virus for the period 2024 – 2025. In this case, a B/Phuket/3073/2013-like virus (B/Yamagata lineage) other than those mentioned above is considered appropriate. Recommendations for the period 20242025 were adopted by the Committee for Medicinal Products for Human Use of Coreper (CHMP) at its March 2024 meeting. Flu viruses, as noted, change and evolve constantly. The periodic replacement of virus strains contained in influenza vaccines is therefore necessary to maintain vaccines effectively, EMA notes. To eliminate another relative? As iatropedia.gr had written, the disappearance of the B-Yamagata strain meant the end for a serious cause of death and illness, especially among children. It also showed that it may be possible in the future to eliminate another related influenza B strain, known as ‘Victoria’. Unlike influenza A, which has a wide range of hosts and threatens to cause pandemics, influenza B strains may be more easily eliminated if more effective vaccines develop that not only protect against the disease, but also prevent transmission, scientists reported in their publication in Lancet Infectious Diseases magazine. ‘The theoretically feasible eradication of influenza virus B could eliminate an important clinical and financial burden,” Florian Krammer, a professor of vaccine at the Icahn School of Medicine at Mount Sinai in New York City and his associates wrote in the inspection. Source: iatropedia.gr