研究原文

https://zenodo.org/record/6291628#.YhuDSi1OIgp

Understanding the circumstances that lead to pandemics is critical to their prevention. Here, we analyze the pattern and origin of genomic diversity of SARS-CoV-2 early in the COVID-19 pandemic. We show that the SARS-CoV-2 genomic diversity prior to February 2020 comprised only two distinct viral lineages—denoted A and B—with no transitional haplotypes. Novel phylodynamic rooting methods, coupled with epidemic simulations, indicate that these two lineages were the result of at least two separate cross-species transmission events into humans. The first zoonotic transmission likely involved lineage B viruses and occurred in late-November/early-December 2019 and no earlier than the beginning of November 2019, while the introduction of lineage A likely occurred within weeks of the first event. These findings define the narrow window between when SARS-CoV-2 first jumped into humans and when the first cases of COVID-19 were reported. Hence, as with SARS-CoV-1 in 2002 and 2003, SARS-CoV-2 emergence likely resulted from multiple zoonotic events.

 

 

 

https://zenodo.org/record/6299600#.YhuExi1OIgp

Geographical clustering of the earliest known COVID-19 cases and the proximity of positive environmental samples to live-animal vendors suggest that the Huanan Seafood Wholesale Market in Wuhan was the site of origin of the COVID-19 pandemic.

3

Abstract:

Understanding the circumstances that lead to pandemics is critical to their

prevention. Here, we analyze the pattern and origin of genomic diversity of SARS

-

CoV

-

2 early

in the COVID

-

19 pandemic. We show that the SARS

-

CoV

-

2 genomic

diversity prior to

February 2020 comprised only two distinct viral lineages

—

denoted A and B

—

with no

transitional haplotypes. Novel phylodynamic rooting methods, coupled with epidemic

simulations, indicate that these two lineages were the result of at least

two separate cross

-

species transmission events into humans. The first zoonotic transmission likely involved

lineage B viruses and occurred in late

-

November/early

-

December 2019 and no earlier than

the beginning of November 2019, while the introduction of l

ineage A likely occurred within

weeks of the first event. These findings define the narrow window between when SARS

-

CoV

-

2 first jumped into humans and when the first cases of COVID

-

19 were reported. Hence, as

with SARS

-

CoV

-

1 in 2002 and 2003, SARS

-

CoV

-

2 em

ergence likely resulted from multiple

3

Abstract:

Understanding the circumstances that lead to pandemics is critical to their

prevention. Here, we analyze the pattern and origin of genomic diversity of SARS

-

CoV

-

2 early

in the COVID

-

19 pandemic. We show that the SARS

-

CoV

-

2 genomic

diversity prior to

February 2020 comprised only two distinct viral lineages

—

denoted A and B

—

with no

transitional haplotypes. Novel phylodynamic rooting methods, coupled with epidemic

simulations, indicate that these two lineages were the result of at least

two separate cross

-

species transmission events into humans. The first zoonotic transmission likely involved

lineage B viruses and occurred in late

-

November/early

-

December 2019 and no earlier than

the beginning of November 2019, while the introduction of l

ineage A likely occurred within

weeks of the first event. These findings define the narrow window between when SARS

-

CoV

-

2 first jumped into humans and when the first cases of COVID

-

19 were reported. Hence, as

with SARS

-

CoV

-

1 in 2002 and 2003, SARS

-

CoV

-

2 em

ergence likely resulted from multiple