WHO Advises Removing Vanished Flu Strain from Future Vaccines
The World Health Organization (WHO) has recommended removing a component from seasonal flu vaccines that protects against the B/Yamagata lineage of influenza viruses, as this strain has not been detected since March 2020. The COVID-19 pandemic disrupted the spread and cycles of other infectious diseases, including the flu, resulting in a virtually nonexistent 2020-2021 flu season and a collapse in the genetic diversity of circulating flu strains. WHO advisors have now recommended excluding the B/Yamagata component from future flu vaccines, as the virus appears to be extinct and its inclusion could pose a theoretical risk of reintroduction.