WHO will continue to closely monitor the situation in China
Geneva: In the last 28 days ( between December 5, 2022, to January 1, 2023), over 14.5 million COVID-19 cases and over 46 000 new fatalities were reported globally – an increase of 25% and 21%, respectively, compared to the previous 28 days, the World Health Organization (WHO) stated today. Its figures showed that as of January 1, 2023, over 656 million confirmed cases and over 6.6 million deaths were reported globally.
However, globally, there was a reduction in weekly cases and deaths of 22% and 12%, respectively although more than 3 million new cases and 10 000 deaths were reported in the week of December 26, 2022, to January 1, 2023.
At the country level, the highest numbers of new weekly cases were reported from Japan (946 130 new cases; -18%), the Republic of Korea (457 745 new cases; -3%), the United States of America (393 587 new cases; -21%), China (218 019 new cases; +45%), and Brazil (206 944 new cases; -19%).
The highest numbers of new weekly deaths were reported from the United States of America (2501 new deaths; -14%), Japan (1941 new deaths; -3%), Brazil (1110 new deaths; +19%), France (803 new deaths; similar to the previous week), and China (648 new deaths; +48%).
WHO though, clarified that current trends in reported COVID-19 cases were underestimates of the true number of global infections and reinfections, considering the reduction in testing and delays in reporting in many countries during the year-end holiday season.
Globally, from December 2, 2022, to January 2, 2023, in all 105 428 SARS-CoV-2 sequences were shared through GISAID (a global science initiative established in 2008 that has provided access to genomic data of influenza viruses, and since the COVID-19 pandemic, has become the world’s largest repository for SARS-CoV-2 strain sequences). Among these, 103 723 sequences were the Omicron variant of concern (VOC), accounting for 98.4% of sequences reported globally in the past 30 days.
BA.5 and its descendent lineages are still dominant globally, accounting for 63.7% of sequences submitted to GISAID as of week 50 (12 to 18 December 2022), even though their prevalence is decreasing. The prevalence of BA.2 and its descendent lineages is rising, mainly due to BA.2.75 ( indicates the inclusion of descendent lineages); together they account for 15.2% of sequences submitted. BA.4 and its descendent lineages are declining with a prevalence of 0.7% as of week 50. Unassigned sequences (presumably Omicron) account for 13.6% of sequences submitted to GISAID in week 50, while the other lineages account for 6.1%.
At the global level, six variants currently under monitoring account for 74.4% of prevalence as of week 50 and have replaced the former BA.5 descendent lineages. These six variants under monitoring (and the respective prevalence) are BQ.1 (44.9%), a sublineage of BA.5, BA.5 with one or several of five mutations (S:R346X, S:K444X, S:V445X, S:N450D, S:N460X) (10.3%), BA.2.75 (11.8%), BA.4.6 (0.6%), and BA.2.3.20 (<0.1%). In week 50, the prevalence of XBB was 6.8%, which includes XBB.1.5 which had an increase in sequences in week 50 (667 sequences) compared
to week 49 (December 5 to 11, 2022) where 525 sequences were reported.
Based on current evidence, there is no indication of increased severity associated with these variants under monitoring compared to the former Omicron lineages, WHO stated.
Meanwhile, the Technical Advisory Group on Virus Evolution (TAG-VE), which advises WHO on whether a change in public health strategies is warranted, met on January 3, 2023, to discuss the COVID-19 situation in mainland China. TAG-VE stated that it was presented genomic data by the Chinese Center for Disease Control and Prevention (China CDC) whose analysis showed a predominance of Omicron lineages BA.5.2 and BF.7 among locally-acquired infections. BA.5.2 and BF.7 together accounted for 97.5% of all local infections as per genomic sequencing. A few other known Omicron sublineages were also detected albeit in low percentages. These variants are known and have been circulating in other countries, and at the present time, no new variant has been reported by the China CDC.
As of January 3, 2023, in all, 773 sequences from mainland China were submitted to the GISAID EpiCoV database, with the majority (564 sequences) collected after December 1, 2022. “Of those, only 95 are labelled as locally-acquired cases, 187 as imported cases and 261 do not have this information provided. Of the locally-acquired cases, 95% belong to BA.5.2 or BF.7 lineages. This is in line with genomes from travellers from China submitted to the GISAID EpiCoV database by other countries. No new variant or mutation of known significance is noted in the publicly available sequence data,” TAG-VE stated.
According to China CDC, the possibility of a large-scale epidemic caused by COVID-19 Omicron XBB sub-variant is low in the short term in China. Chinese news agency Xin Hua quoted Xu Wenbo, director of the National Institute for Viral Disease Control and Prevention under the China CDC, as saying that China detected BF.7, BQ.1, and XBB imports in the past three months, but BQ.1 and XBB sub-variants have not developed into dominant sub-variants in the country.
While the TAG-VE is also evaluating the rapidly increasing proportion of XBB.1.5 in the United States and other countries, WHO stated it will continue to closely monitor the situation in China and globally. WHO’s emergencies director Dr Mike Ryan said that the current numbers being published in China underrepresent the true impact of the disease in terms of hospital admissions, in terms of ICU admissions, particularly in terms of deaths. It urged all countries to continue to be vigilant, to monitor and report sequences, as well as to conduct independent and comparative analyses of the different Omicron sublineages, including on the severity of the disease they cause.
– global bihari bureau
