February 8, 2023 – After the top of the zero-COVID policy in China, no recent COVID-19 variants emerged in the most recent wave of infections, in line with a analysis Published in The Lancet.
Genome evaluation of 413 recent infections in Beijing since strict pandemic controls were lifted suggests they were all attributable to existing viruses. The Lancet said.
“More than 90% of local infections in Beijing between November 14 and December 20, 2022, involved the Omicron subvariants BA.5.2 or BF.7,” The Lancet “The imported cases during the same period were mostly variants other than those prevalent in Beijing,” he said.
China reportedly ended its zero-COVID strategies in December, which included targeted lockdowns, mass testing and quarantines. Case numbers have skyrocketed, raising fears that recent variants could emerge. The Lancet said.
Variants resembling Alpha, Beta, Gamma, Delta and Omicron have caused waves of cases all over the world because the pandemic began. Observers have been concerned because the policy change that recent strains could emerge in China.
The study authors analyzed local and imported cases in Beijing since December 2019 and concluded that no sustained local transmissions were reported in Beijing before last December.
“Due to frequent population exchange and the presence of circulating strains with high transmissibility, the results can be considered a snapshot of China,” the study said.
In the present study, they examined COVID-19 samples from Beijing last 12 months. “Genome sequences were generated using rapid, large-scale sequencing technology and their evolutionary history and population dynamics were analyzed using existing high-quality COVID-19 sequences,” The Lancet said a press release.
More than 400 samples were analyzed and all of them were found to belong to existing strains. The dominant strain in Beijing after November 14, 2022 was BF.7, accounting for 75.7% of local infections, while BA5.2 accounted for 16.3%.