CDC team identifies origin of virus in 16 hours

Writer: Zhang Yu, Zhang Yingxi  |  Editor: Holly Wang  |  From: Shenzhen Daily  |  Updated: 2022-01-14

The virus origin-tracing team of the Shenzhen Center for Disease Control and Prevention (CDC) took only 16 hours to identify the COVID-19 variant of the first and second confirmed cases in the city’s latest COVID resurgence, eight hours faster than before, Shenzhen Economic Daily reported Thursday.

For several days in a row, the team had been busy working at the emergency laboratory building since the first positive nucleic acid test sample, detected in the latest COVID outbreak Jan. 7, was sent to the lab.

The first four cases were infected with the Delta variant (AY.103 sublineage) amid the recent COVID resurgence, which was most likely caused by contaminated imported goods based on a comprehensive analysis, according to the municipal health authority Monday.

Shenzhen CDC’s virus origin-tracing team had worked against time to pinpoint the virus’ origin, according to the Daily report.

“The sooner the virus origin is confirmed, the better odds we have in the battle against COVID,” He Yaqing, the team’s leader, told the Daily.

Gene sequencing necessitates a series of procedures including sample pretreatment, library construction, sequencing reaction, and bioinformatics analysis. Among them, library construction includes RNA reverse transcription and amplification.

“Every step of the gene sequencing process is closely linked. When local infections occur, everyone is vigilant and dares not lower their guard,” He was quoted as saying.

According to He, it is greatly significant to trace the virus’ origin when locally transmitted COVID cases appear. “We must first determine the virus’ type and origin. We’ll designate key populations and areas, as well as prevention and control measures to use for different types of COVID-19 variants.”

She added that gene sequencing can be used to determine whether infections are caused by the same source.

He’s virus-origin tracing team, established in January 2020, is composed of young members mostly born after 1900, with some born after 2000.

“Tracing the virus’ origin is not an easy job. We often have to race against the virus,” He said. He added that the young people are energetic, motivated, quick to learn and willing to persevere in the face of adversity, which is in line with gene traceability research.