did not originate in Wuhan seafood market, Chinese scientists say
of genomic data from 93 samples of the novel coronavirus suggests it
was imported from elsewhere
busy market then boosted its circulation and spread it to the whole
city, research shows
23 February, 2020
novel coronavirus that has claimed the lives of more than 2,400
people did not originate at a seafood market in the central China
city of Wuhan as was first thought, according to a new study by a
team of Chinese scientists.
severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was
instead imported from elsewhere, said researchers from Xishuangbanna
Tropical Botanical Garden under the Chinese Academy of Sciences and
the Chinese Institute for Brain Research.
team, led by Dr Yu Wenbin, sequenced the genomic data of 93
SARS-CoV-2 samples provided by 12 countries in a bid to track down
the source of the infection and understand how it spreads.
they found was that while the virus had spread rapidly within the
Huanan Seafood Wholesale Market in Wuhan, there had also been two
major population expansions on December 8 and January 6.
to the study, which was published on the institute’s website on
Thursday, analysis suggested that the coronavirus was introduced from
outside the market.
crowded market then boosted SARS-CoV-2 circulation and spread it to
the whole city in early December 2019,” it said.
reports by Chinese health authorities and the World Health
Organisation said that the first known patient showed symptoms on
December 8, and that most of the subsequent cases had links to the
seafood market, which was closed on January 1.
research went on to say that based on the genome data it was possible
that the virus began spreading from person to person in early
December or even as early as late November.
study concerning whether Huanan market is the only birthplace of
SARS-CoV-2 is of great significance for finding its source and
determining the intermediate host, so as to control the epidemic and
prevent it from spreading again,” the research team said.
scientists said also that although China’s National Centre for
Disease Control and Prevention issued a Level 2 emergency warning
about the new coronavirus on January 6, the information was not
the warning had attracted more attention, the number of cases both
nationally and globally in mid-to-late January would have been
reduced,” they said.
Xiang Nijuan, a researcher at the Chinese Centre for Disease Control
and Prevention, said in an interview with state broadcaster CCTV on
Saturday that people infected with the new coronavirus were
contagious two days before they showed any symptoms.
anyone who had been in close contact with someone within 48 hours of
them being confirmed as infected should put themselves in isolation
for 14 days, he said.
Chinese study indicates novel coronavirus did not originate in Huanan
The Wuhan seafood market, which is at the centre of the pneumonia outbreak, has been closed. (Photo: Handout)
new study by Chinese researchers indicates the novel coronavirus may
have begun human-to-human transmission in late November from a place
other than the Huanan seafood market in Wuhan.
study published on ChinaXiv, a Chinese open repository for scientific
researchers, reveals the new coronavirus was introduced to the
seafood market from another location, and then spread rapidly from
market to market. The findings were the result of analyses of
genome-wide data, sources of infection and the route of spread of 93
samples of the novel coronavirus collected from 12 countries across
study believes that patient zero transmitted the virus to workers or
sellers at the Huanan seafood market. The crowded market facilitated
the further transmission of the virus to buyers, which caused a wider
spread in early December 2019.
to the researchers, the new coronavirus experienced two sudden
population expansions, including one on January 6, 2020, which was
related to the Chinese New Year’s Day holiday.
earlier expansion occurred on December 8, implying human-to-human
transmission may have started in early December or late November, and
then accelerated when it reached the Huanan seafood market.
January 6, the National Center for Disease Control and Prevention
(CDC) issued a second-level emergency response, which the researchers
said served as a warning against mass public activity and travel.
the warnings had received wider public attention, the number of cases
spreading nationally and globally in mid-to-late January would have
been lower, said the researchers.
from Australia, France, Japan and the US – countries with wider
samples – have had at least two sources of infection, and the US in
particular has reported five sources, the study said.
based upon limited samples in other countries, the source of most
infections is deemed to be the same. In addition to their contact
history with Wuhan, some may have been infected in South China’s
Guangdong Province and Singapore.