3 ms·

Seems dubious. Everything we know about the phylogenesis of SARS2 points to the origin being China. All RNA sequences that were published have been shown [1] to

by jupp0r 7y ago

Seems dubious. Everything we know about the phylogenesis of SARS2 points to the origin being China. All RNA sequences that were published have been shown [1] to be mutations of earlier samples from Wuhan. If we would have had community transmission in France in late December, we would see that being a distinct branch in the genealogy. We don't see that, all RNA we've seen being sequenced in Europe is descended from China. [1] https://nextstrain.org/ncov/global https://nextstrain.org/ncov/global

ahmedalsudani 7y ago
IIRC, I read that we think it broke out into humans in November -- so this does not contradict Wuhan being the where this thing started.
hazeii 7y ago
The detail is his wife worked at a supermarket near the main Paris airport, and had often had travellers (inc. from China) coming in, straight off the plane [0]. So one suggestion is she was caught it and was asymptomatic, and he caught it from her. [0] https://www.bbc.co.uk/news/world-europe-52526554 https://www.bbc.co.uk/news/world-europe-52526554
not_a_moth 7y ago
Why wouldn't this suggest to you it was spreading from China in December?
- jupp0r 7y ago
  What happened to the strain of the virus? The previously known first case in France is this one [1]. If there was community transmission in France for a month, we should see different mutations than the ones in China. [1] https://nextstrain.org/ncov/global?branchLabel=aa&dmax=2020-01-27&s=France/IDF0372/2020 https://nextstrain.org/ncov/global?branchLabel=aa&dmax=2020-...
  - not_a_moth 7y ago
    To be clear, the claim is if there was earlier community spread, the current virus in France should look different because of presumed mutation rates, because right now it looks similar to China?
    - jupp0r 7y ago
      I don’t think the current virus would need to look different. For the other first few cases in France a month later, we are relatively sure that they come from China because their RNA has mutations that have nit been there in December. If there would have been transmission in France in December, we would expect to see a strain if the virus without the mutations that happened in China in January (but potentially with different mutations). This makes me think that either 1. nobody else in France was infected by the spread that they now found to have happened in December, the strain died 2. the findings are wrong 1 seems pretty unlikely. We’ll know once they hopefully sequence and publish the genome of the virus they found.
loulouxiv 7y ago
The french Institut Pasteur has sent to preprint a genetic study which tends to show that the coronavirus was silently spreading in france in february, as as distinct branch from those in other auropen countries. This was sent to preprint before this other study was made public : https://www.sciencedirect.com/science/article/pii/S0924857920301643 https://www.sciencedirect.com/science/article/pii/S092485792... . In this paper, another team looked back at records of patient showing flu-like symptoms before the supposed start of outbreak in France. They discovered by PCR testing archived samples that one of these french patients was positive to SARS-Cov-2 in late december

by jupp0r 7y ago

ahmedalsudani 7y ago

IIRC, I read that we think it broke out into humans in November -- so this does not contradict Wuhan being the where this thing started.

hazeii 7y ago

The detail is his wife worked at a supermarket near the main Paris airport, and had often had travellers (inc. from China) coming in, straight off the plane [0]. So one suggestion is she was caught it and was asymptomatic, and he caught it from her. [0] https://www.bbc.co.uk/news/world-europe-52526554 https://www.bbc.co.uk/news/world-europe-52526554

not_a_moth 7y ago

Why wouldn't this suggest to you it was spreading from China in December?

jupp0r 7y ago
What happened to the strain of the virus? The previously known first case in France is this one [1]. If there was community transmission in France for a month, we should see different mutations than the ones in China. [1] https://nextstrain.org/ncov/global?branchLabel=aa&dmax=2020-01-27&s=France/IDF0372/2020 https://nextstrain.org/ncov/global?branchLabel=aa&dmax=2020-...
- not_a_moth 7y ago
  To be clear, the claim is if there was earlier community spread, the current virus in France should look different because of presumed mutation rates, because right now it looks similar to China?
  - jupp0r 7y ago
    I don’t think the current virus would need to look different. For the other first few cases in France a month later, we are relatively sure that they come from China because their RNA has mutations that have nit been there in December. If there would have been transmission in France in December, we would expect to see a strain if the virus without the mutations that happened in China in January (but potentially with different mutations). This makes me think that either 1. nobody else in France was infected by the spread that they now found to have happened in December, the strain died 2. the findings are wrong 1 seems pretty unlikely. We’ll know once they hopefully sequence and publish the genome of the virus they found.

loulouxiv 7y ago

The french Institut Pasteur has sent to preprint a genetic study which tends to show that the coronavirus was silently spreading in france in february, as as distinct branch from those in other auropen countries. This was sent to preprint before this other study was made public : https://www.sciencedirect.com/science/article/pii/S0924857920301643 https://www.sciencedirect.com/science/article/pii/S092485792... . In this paper, another team looked back at records of patient showing flu-like symptoms before the supposed start of outbreak in France. They discovered by PCR testing archived samples that one of these french patients was positive to SARS-Cov-2 in late december