https://www.sciencedirect.com/science/article/pii/S0013935122013068
Many of you may recall a study from over two years ago which found traces of covid RNA in sewage water in Lombardy, Italy.
This is not that study. This is a study released this month which confirms those earlier findings. A new strain which predates the Wuhan alpha strain was sequenced, labeled proCoV2.
Abstract
As a reference laboratory for measles and rubella surveillance in Lombardy, we evaluated the association between SARS-CoV-2 infection and measles-like syndromes, providing preliminary evidence for undetected early circulation of SARS-CoV-2. Overall, 435 samples from 156 cases were investigated.
RNA from oropharyngeal swabs (N = 148) and urine (N = 141) was screened with four hemi-nested PCRs and molecular evidence for SARS-CoV-2 infection was found in 13 subjects. Two of the positive patients were from the pandemic period (2/12, 16.7%, March 2020–March 2021) and 11 were from the pre-pandemic period (11/44, 25%, August 2019–February 2020).
Sera (N = 146) were tested for anti-SARS-CoV-2 IgG, IgM, and IgA antibodies. Five of the RNA-positive individuals also had detectable anti-SARS-CoV-2 antibodies. No strong evidence of infection was found in samples collected between August 2018 and July 2019 from 100 patients. The earliest sample with evidence of SARS-CoV-2 RNA was from September 12, 2019, and the positive patient was also positive for anti-SARS-CoV-2 antibodies (IgG and IgM).
Mutations typical of B.1 strains previously reported to have emerged in January 2020 (C3037T, C14408T, and A23403G), were identified in samples collected as early as October 2019 in Lombardy. One of these mutations (C14408T) was also identified among sequences downloaded from public databases that were obtained by others from samples collected in Brazil in November 2019.
We conclude that a SARS-CoV-2 progenitor capable of producing a measles-like syndrome may have emerged in late June-late July 2019 and that viruses with mutations characterizing B.1 strain may have been spreading globally before the first Wuhan outbreak.
Our findings should be complemented by high-throughput sequencing to obtain additional sequence information. We highlight the importance of retrospective surveillance studies in understanding the early dynamics of COVID-19 spread and we encourage other groups to perform retrospective investigations to seek confirmatory proofs of early SARS-CoV-2 circulation.
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What mechanism for contamination do you suggest here? They have found antibodies too. As far as I can see contamination is quite unlikely. This is the second study in the vein and they also found no evidence in samples before a certain time period. I really struggle to find any likely way this could be due to contamination.
Yeah unless they sprayed vaccine into the samples I don't see it being contaminated with antibodies. A sure sign of contamination would be seeing variants of COVID that have arisen more recently, but they didn't find that.
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That's not sufficient. You need to also coincidentally not have any contamination for the samples outside the time period, and you need the control samples to still be negative, and of course you need the contamination to go in the same way for both ELISA and PCR.
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That doesn't make sense. If you think that there is a general contamination in the lab, then it would be exceedingly unlikely to get a consistent negative result on all the samples before a given time period. And while one might think that RNA contamination could have happened at a coincidental time of testing to only happen for a sample past a certain date, for it to happen at the same point for the serological data is highly unlikely.
Also, ELISA is far less sensitive than a PCR test. Like, 3 orders of magnitude less. And RNA is far more stable than antibodies, too. So again, double contamination segmented cleanly around a coincidental points is massively unlikely.
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Yes this is literally what I just mentioned in the comment you replied to. If this was a sequential contamination issue you would need contamination at the same point in time both for antibodies and RNA.
Sequencing the samples is something they say they want to do on the paper. It's not going to be easy at all to sequence these samples that are going to have RNA from thousands of other organisms.
Last I had seen bat's from Laos had the most similar genetics, is that not the case any more? I've more or less stopped watching, because I'm more of a macroevolution guy
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Fifteen professors co-signed a rebuttal letter to that one because they found it unconvincing. I also don't trust the motives of its author Kristian Andersen because he was caught playing underhanded in FOIA requests. I think he's an obfuscator.
If there were only one positive sample, I would agree. But this is 11 positive samples. And it conforms to sewage and antibody studies from across the globe. All samples from before September 2019 were negative.
Except for this study? They sequenced ProCov2.
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