Today, Chinese media, citing a May 16 report from the China Center for Disease Control and Prevention Weekly Report, reported the first confirmed case of a new strain of Omicron coronavirus subtype BA.2.12.1.
As early as April 23, 2022, international flight KQ880 from Nairobi, Kenya reportedly arrived at Guangzhou Baiyun International Airport in Guangdong. All passengers were transferred to quarantine hotels for 14 days for routine medical observation and routine nucleic acid testing.
One of the patients, a 27-year-old passenger on this flight, reported positive for the nucleic acid of the novel coronavirus on April 27, 2022. The patient had a complete history of Covid-19 vaccination and had no contact with other Covid-19 cases in the last 14 days. After being diagnosed, he was transferred to Guangzhou Eighth People's Hospital for treatment.
On April 30, 2022, a nasal swab sample from the patient was sequenced using the Illumina MiniSeq platform, and genotyping results indicated that the patient was infected with the BA.2.12.1 strain of the Omicron subtype. A total of 33 amino acid mutation sites were found in the spike gene. Among them, L452Q and S704L are the key loci of the BA.2.12.1 subline. The sequence has been sent to the National Genome Data Center. Authorities fear that BA.2.12.1 is about 25% more contagious than the BA.2 subtype, which is common in Germany.
On May 4, 2022, the World Health Organization recalled the close monitoring of subtype BA.2.12.1. The BA.2.12.1 subtype has a stronger immune evasion ability than other strains of the Omicron subtype, and some studies have shown that BA.2.12.1 spreads 23–27% faster than BA.2. This strain spread very quickly, causing a re-emergence of the epidemic in many parts of the United States, with cases reported in at least 17 countries.