Restrictions in place to halt the coronavirus pandemic have stifled the flu season in 2020-2021, with so few cases that scientists hypothesize that one of the major flu strains may become extinct because there are no people to infect it.
One of the four influenza strains, the B/Yamagata strain, is regularly included in annual influenza vaccinations. However, amid the lockdowns imposed against Covid-19, it appears to have “completely disappeared from radar screens,” Australian researchers wrote in a study published in the scientific journal Nature Reviews.
B/Yamagata strains have not been isolated or sequenced in identifying influenza cases since March 2020, when restrictions imposed to halt the coronavirus pandemic ended the 2019-2020 influenza season.
Only 31 suspected cases of B/Yamagata were reported to public health authorities during the flu season yesterday, but none were successfully identified or genetic sequenced to establish them: in fact, it is the B/Yamagata strain that is responsible for the diseases.
The B/Yamagata strain has always been less contagious than the other three strains and has not developed as aggressively as the others: vaccine manufacturers have not had to update the B/Yamagata component of their annual influenza vaccines since 2015.
Combined with the conditions of the Covid-19 pandemic, these factors may have limited the global spread of the B/Yamagata strain and the potential extinction of this strain, writes a team led by Marius Kotsakos, a researcher at the University of Melbourne.
If the entire influenza strain does become extinct, it will open up new avenues for treating annual influenza outbreaks, US epidemiologists believe, however, they caution, saying it will take more than a season to determine the extinction of the B/Yamagata strain.
Richard Kennedy, chief vaccine researcher at the Mayo Clinic in Rochester, states that the B/Yamagata strain only appears in certain years and then disappears at other times, according to medicalxpres.com news portal. (MTI)
