Shanghai has detected the Omicron subvariants BQ.1 and XBB that have been prevailing in some overseas countries but experts said the two mutant strains were found in imported cases placed under closed-loop management which has not caused local transmission, saying there is no need to hoard Montmorillonite powder to relieve diarrhea that can be caused by subvariant XBB.1.5.
A total of 369 viral sequencing results of the local COVID-19 cases in China have been shared by a Shanghai research team with the Global Initiative on Sharing All Influenza Data (GISAID). They showed that at least 30 known Omicron subvariants have been detected in Shanghai but no new variant has been identified, according to media reports.
These samples randomly collected from COVID-19 patients in Shanghai between November 23 and December 22 in 2022 showed that apart from the BA.5.2 variant spreading in the southern China and the BF.7 variant spreading in the northern region, Omicron subvariants BQ.1 and XBB widely spread in some overseas countries have also been found in Shanghai.
However, the great majority of the patients infected with BQ.1 and XBB were imported cases placed under closed-loop management so that they did not cause large-scale local transmission, according to the joint research team of Ruijin Hospital affiliated to the School of Medicine of Shanghai Jiao Tong University and Shanghai Public Health Clinical Center.
Yuan Zheng'an, member of the city's epidemic prevention and control work group, also confirmed that so far, the Omicron variants BQ.1 and XBB found in Shanghai have only been detected in a very small number of inbound travelers quarantined upon their arrivals and have not caused local transmission in communities, Shanghai Observer reported on Monday.
Meanwhile, as the designated hospital for treatment on imported confirmed COVID-19 cases, Shanghai Public Health Clinical Center has implemented strict closed-loop management on imported cases as required, and the patients will only be released from quarantine after meeting the criteria for discharge from hospital, Ling Yun, deputy director from the Shanghai Public Health Clinical Center, told Shanghai Observer, noting that the two mutant strains have not yet caused local transmission in communities.
Among the 25 samples of XBB variants detected in Shanghai, three were identified as XBB.1.5 subvariants, which has become dominant in the US, accounting for about 41 percent of confirmed COVID cases across the country, according to the data published by the US Centers for Disease Control and Prevention on December 30, 2022.
