Groundbreaking virus tracing result published

►China submits latest genome sequence to WHO at record speed

From Beijing’s Xinfadi market, where the capital’s outbreak flared up, virologists from China’s Center for Disease Control and Prevention (CDC) took substantial coronavirus-positive samples three times and published a groundbreaking discovery that the virus causing Beijing’s latest outbreak came from Europe, yet it has existed longer than the coronavirus strain in Europe, or may be more contagious.

Chinese scientists spent only a week to work out the genome sequence data of the coronavirus that caused Beijing’s outbreak and shared it with the international community, a development that experts said could assist virus tracing and finding patient zero in the capital to stem the spread.

Experts suspect that a super spreader may be lurking in the capital, as the market was severely contaminated by the virus and a large number of patients, all linked to Xinfadi, have been found in Beijing. But it raised the question of whether the outbreak had been brought under control in the capital.

New finding

The finding that the coronavirus strain detected at Xinfadi in Beijing came from Europe was included in a detailed epidemiological survey published on the website of the Communist Party of China (CPC) Central Com

mission for Discipline Inspection (CCDI) on Friday, yet the virus found in Xinfadi has existed lo longer than the coronavirus strain circulating in E Europe, CDC virologists said.

Since the outbreak, virologists from China’s C CDC have visited the now closed market three ti times – on June 14, 15 and 17 – and announced a gr groundbreaking discovery.

The coronavirus is particularly cold-resistant an and can survive for months at -4 C and 20 years at -20 C, which explains why the virus has been fo found several times in seafood markets, and can b be transported across borders, Chinese epidemiol ologist Li Lanjuan said on Friday.

Experts said it is possible that the virus did not mutate during transport as it has been se sealed in frozen food, and stored in cold and d damp conditions.

Based on the known facts, we can speculate th that the virus that caused Beijing’s latest outbr b break existed as early as January, Yang Zhanqiu, d deputy director of the pathogen biology department at Wuhan University, told the Global Times, noting that almost 200 people got infe fected within a week, meaning the virus is more co contagious than its Chinese peer.

The virus may be a subtype of the coronaviru rus in Europe, and no matter when it came to C China, it only caused the outbreak now because di different races have different immunities to the vi virus, Yang said. He explained it is possible the vi virus from Europe may not easily infect Asians, or take longer for Asians to contract the virus.

The CDC published the genome sequence d data of the coronavirus that caused the latest COVID-19 outbreak in Beijing. The data has also been submitted to the World Health Organizati tion. This time, it took a week for China’s CDC to share the coronavirus genome sequence with W WHO and publish it on GISAID after Beijing’s ou outbreak flared up on June 11. It took Wuhan 16 d days to do the same during the first outbreak in Ja January.

Jin Dongyan, a professor at the School of Biomedical Sciences at the University of Hong Kong, said that the coronavirus genome se sequencing data, together with epidemiologic inve vestigations, could help scientists better analyze th the source of the virus – whether it’s more like th the virus in Europe.

Stemming transmission routes

Wu Zunyou, the chief epidemiologist of CDC, sa said Thursday the capital’s coronavirus outbreak h has been brought under control.

Wu told the Global Times that his conclusion was based on science, instead of a wild guess. But prevention measures cannot be relaxed.

“Beijing’s tough measures have stemmed tr transmission routes of the virus… It is difficult fo for the virus to spread further under such airti tight prevention measures,” Wu noted, saying th the measures will be relaxed once no new infecti tions are reported for two weeks.

Jin believes it’s too early to conclude that Beijing’s recent outbreak has been brought under control, as there are still many unsolved problems.

One was whether the virus has circulated for a long time before being noticed. We need to co conduct antibody tests on people involved in the X Xinfadi market infections to see how long the vi virus had been existing, Jin said.