The Joint Team set up by the World Health Organisation (WHO) has reported that Bats and Pangolins are not direct progenitors of COVID-19 cases studied in China.
The report states that “…neither of the viruses identified so far from these mammalian species is sufficiently similar to SARS-CoV-2 to serve as its direct progenitor.”
This is one of the highlight of the WHO-Convened Global Study of Origins of SARS-CoV-2 in China.
WHO in conjunction with China and other global organisations conducted a 28-day joint study from 14 January to 20 February, 2021 to trace the origin of the coronavirus in China.
Here is the highlight of the final report of the joint team.
The Widespread Started in Wuhan, China
According to the report, COVID-19 transmission was widespread among the population of Wuhan by the first week of 2020 before it spreads to the rest of Hubei Province.
“The documented rapid increase in all-cause mortality and pneumonia-specific deaths in the third week of 2020 indicated that virus transmission was widespread among the population of Wuhan by the first week of 2020. The steep increase in mortality that occurred one to two weeks later among the population in the Hubei Province outside Wuhan suggested that the epidemic in Wuhan preceded the spread in the rest of Hubei Province.”
No firm conclusion about the role of the Huanan market in the origin of the outbreak
The team conclude “Transmission within the wider community in December could account for cases not associated with the Huanan market which, together with the presence of early cases not associated with that market, could suggest that the Huanan market was not the original source of the outbreak.”
Bats and pangolins are not direct origin of the coronavirus
“Evidence from surveys and targeted studies so far have shown that the coronaviruses most highly related to SARS-CoV-2 are found in bats and pangolins, suggesting that these mammals may be the reservoir of the virus that causes COVID-19. However, neither of the viruses identified so far from these mammalian species is sufficiently similar to SARS-CoV-2 to serve as its direct progenitor. In addition to these findings, the high susceptibility of mink and cats to SARS-CoV-2 suggests that additional species of animals may act as a potential reservoir.”
COVID-19 outbreak commenced around mid-November and early December.
“Based on molecular sequence data, the results suggested that the outbreak may have started some time in the months before the middle of December 2019. The point estimates for the time to the most recent ancestor ranged from late September to early December, but most estimates were between mid-November and early December.”
The Virus Can be found in and transferred through Frozen Food
The team also report that “SARS-CoV-2 has been found to persist in conditions found in frozen food, packaging and cold-chain products. Index cases in recent outbreaks in China have been linked to the cold chain; the virus has been found on packages and products from other countries that supply China with cold-chain products, indicating that it can be carried long distances on cold-chain products.”
The identified possible pathways of early transmission of the Virus are:
- direct animals; which is graded to be possible to likely pathway
- an intermediate host; a likely-very likely pathway
- frozen food chain; a possible pathway