A recent analysis of COVID-19 cases in Beijing has revealed that no new variants of the virus have emerged in the latest outbreak, according to a recent study published in The Lancet.
More than 90% of local infections in Beijing between Nov. 14 and Dec. 20, 2022, were BA.5.2 and BF.7, two existing Omicron sub-variants of COVID-19. The timeframe of the study fell as China officially ended its zero-tolerance COVID-19 policy on Dec. 7, 2022.
Researchers view Beijing as a good snapshot of the pandemic in China due to its population size and the circulation of the high transmissible strains of the virus there. Since the zero-tolerance policy ended late last year, rising case numbers have caused concern that new variants could emerge. Multiple waves of COVID-19 infections over the last few years have created several new variants, including Alpha, Beta, Gamma, Delta and Omicron.
Study authors looked at COVID-19 samples detected in Beijing in 2022, using genome sequencing to determine variants. Of the 413 new sequences in the analysis, all were known COVID-19 strains. The 413 sequences included 350 local cases and 63 imported cases.
“Although our data were only from Beijing, the results could be considered a snapshot of China, due to the frequent population exchange and the presence of circulating strains with high transmissibility,” wrote first author Yang Pan, PhD, of the Beijing Center for Disease Prevention and Control, Beijing, China, et al.
BF.7 accounted for 75.7% of local infections, while BA.5.2 was responsible for 16.3% of local cases. Populations of both strains increased after Nov. 14, 2022.
“Given the impact that variants have had on the course of the pandemic, it was important to investigate whether any new ones emerged following the recent changes to China’s COVID-19 prevention and control policies,” said lead author Professor George Gao, of the Institute of Microbiology at the Chinese Academy of Sciences. “Our analysis suggests two known Omicron sub-variants––rather than any new variants––have chiefly been responsible for the current surge in Beijing, and likely China as a whole. However, with ongoing large-scale circulation of COVID-19 in China, it is important we continue to monitor the situation closely so that any new variants that might emerge are found as early as possible.”
The study authors noted that “the BA.5-derived subvariant BQ.1, its subvariant BQ.1.1, and XBB (a recombinant of two BA.2 subvariants) are spreading globally.” Though, XBB, BQ.1, and BQ.1.1 were not detected in local cases in the study.
In the United States, XBB.1.5 has recently become the most dominant strain of the virus, according to the Centers for Disease Control and Prevention (CDC)’s latest data tracker weekly review. XBB.1.5 accounted for 75% of new COVID-19 cases in the U.S. as of Feb. 10.
Amy joined TriMed Media as a Senior Writer for HealthExec after covering home care for three years. When not writing about all things healthcare, she fulfills her lifelong dream of becoming a pirate by sailing in regattas and enjoying rum. Fun fact: she sailed 333 miles across Lake Michigan in the Chicago Yacht Club "Race to Mackinac."