On December 16, the Chinese Center for Disease Control and Prevention Weekly Report reported the specific situation of the First Omikejong variant detected in China.
On December 9, 2021, two international passengers arrived at Tianjin Binhai International Airport by plane from Warsaw, Poland, and were identified as asymptomatic infected with the new crown virus through nucleic acid testing.
The first case (patient A) is a crew member, 35 years old male, who returned to Warsaw on the same flight on 10 December 2021. The second case (patient B) is a 17-year-old female student who has been transferred to Haihe Hospital for isolation. Both cases were polish nationals who had recently resided in Warsaw.
After investigation, the patient had no symptoms of the disease and a history of medication. Patient B was vaccinated against COVID-19 with Pfizer BNT162b2 on 27 September 2021. Patient A was vaccinated on 25 May 2021, but no further vaccine information was collected as Patient A had left China. No other cases of infection were detected on this flight.
On December 10, 2021, the Tianjin Municipal Center for Disease Control and Prevention collected respiratory specimens from two infected people for whole genome sequencing and sequence analysis of the new coronavirus, and obtained the sequencing results on December 13.
Compared with the virus found in Wuhan, the viral nucleotide sequence of patient A had 58 replacements, 39 deletions, and 9 insertions (genome coverage rate of 99.62%), which belonged to the Pango line BA.1 (alias B.1.1.529.1). Due to the low viral load, the coverage of the B viral genome in patients was only 92.62%. Based on the detected characteristics of 50 replacements and 3 deletions, the strain of patient B belongs to B.1.1.529. Following the Alpha, Beta, Gamma, and Delta variants, the World Health Organization (WHO) designated B.1.1.529 and its descendants (BA.1 and BA.2) as the fifth SARS-CoV-2 variant (VOC), named Omicron. South Africa first reported the Ormikeron variant to WHO on 24 November 2021. As of December 14, 2021, 55 countries have uploaded 4,265 Opichron genome sequences by the Global Influenza Data Sharing Initiative (GISAID).
40 amino acid mutation sites and at least 26 amino acid mutation sites were detected from the spike proteins of patient A and patient B strains, respectively. Some mutations near receptor-binding domains and furin protease sites may be associated with increased immune evasion or increased infectivity.
Today, Ami kerong is showing a faster growth trend than other variants in many countries around the world. In addition, preliminary experimental data suggest that Omiljung showed reduced immune protection against vaccines.
"Weekly" pointed out that the strains found in the two cases in Tianjin are the first imported Aomi Kerong variants found in the mainland, posing a huge potential threat to the prevention and control of the new crown pneumonia epidemic in China. The transmissibility, pathogenicity and immune escape ability of Omikejong need to be further studied.
