4 ms·

Coronavirus traces found in March 2019 sewage sample, Spanish study

18 points by ljf 6y ago

darkerside 6y ago
This seems like it must be a typo. March of 2019??? That doesn't compute at all.
- ancarda 6y ago
  It's not a typo. The article points out how early it is: >The discovery of virus genome presence so early in Spain, if confirmed, would imply the disease may have appeared much earlier than the scientific community thought. >The University of Barcelona team, who had been testing waste water since mid-April this year to identify potential new outbreaks, decided to also run tests on older samples.
- a1369209993 6y ago
  It not a typo, it's a (single) incorrect test result, probably due to contamination, operator error, noise, or expected defects in testing supplys. (It might be some other coronavirus (there are plenty). It theoretically might be COVID-19, but as you note, that's incredibly unlikely.)
- dragonwriter 6y ago
  It's very unlikely to actually be COVID-19, but the sample was actually from March of 2019. Others have covered many of the ways it could be wrong, but things like this are important to point out when found if no clear (rather than suspected, unconfirmed) source of error can be identified because it provides indications for follow-up, and even things that are 99.9% likely to be error will indicate a surprising new piece of information 0.1% of the time, and if you ignore it, the world will miss those. OTOH, things this improbable to be correct get presented inaccurately and as far more likely to be correct (or as perceived by the scientific community as such) than they are, which helps foster “science fatigue” in the public.
tyfon 6y ago
Curious about how accurate these tests are. The recent coronavirus is just one of many in a family that also includes common cold as written in the article, "There was the potential for a false positive due to the virus’ similarities with other respiratory infections". Considering this is just one test out of many that came back positive and the next positive result was in January 2020 I suspect it's just that, a false positive. But it makes for a good headline.
deleted 6y ago
[deleted]
Izkata 6y ago
The paper itself was posted yesterday, with a lot of criticism: https://news.ycombinator.com/item?id=23652804 https://news.ycombinator.com/item?id=23652804
- abathur 6y ago
  Thanks for pointing to this. I missed it yesterday. A little disappointed in Reuters for the handling of this. I wish news outlets were treating direct reporting of single-study-preprint (i.e., just credulously reporting the preprint's claims with no attempt to seek expert feedback) as roughly equivalent of publishing a single-anonymous-source article without bothering to fact check. There might be circumstances where it's merited--but they'll be extraordinary, and you should probably feel compelled to explain why you think it's important enough to break the norm.
- ljf 6y ago
  Thanks for this - I hadn't seen that yesterday, and wouldn't have posted this otherwise. My wife has had long term post-covid symptoms and goes in a slack group to discuss and this was posted and I thought it was interesting. I'll flag this post myself.
ageitgey 6y ago
They had one partial positive test result from one random sample taken in March 2019. None of the samples taken during the following months tested positive until Jan 15, 2020. The paper is a preprint that hasn't been peer reviewed. The overwhelmingly likely explanation is one incorrect test result due to something like an imperfect test or cross contamination. You would need much better evidence than that to rewrite the entire timeline of this disease.

18 points by ljf 6y ago

darkerside 6y ago

This seems like it must be a typo. March of 2019??? That doesn't compute at all.

ancarda 6y ago
It's not a typo. The article points out how early it is: >The discovery of virus genome presence so early in Spain, if confirmed, would imply the disease may have appeared much earlier than the scientific community thought. >The University of Barcelona team, who had been testing waste water since mid-April this year to identify potential new outbreaks, decided to also run tests on older samples.
a1369209993 6y ago
It not a typo, it's a (single) incorrect test result, probably due to contamination, operator error, noise, or expected defects in testing supplys. (It might be some other coronavirus (there are plenty). It theoretically might be COVID-19, but as you note, that's incredibly unlikely.)
dragonwriter 6y ago
It's very unlikely to actually be COVID-19, but the sample was actually from March of 2019. Others have covered many of the ways it could be wrong, but things like this are important to point out when found if no clear (rather than suspected, unconfirmed) source of error can be identified because it provides indications for follow-up, and even things that are 99.9% likely to be error will indicate a surprising new piece of information 0.1% of the time, and if you ignore it, the world will miss those. OTOH, things this improbable to be correct get presented inaccurately and as far more likely to be correct (or as perceived by the scientific community as such) than they are, which helps foster “science fatigue” in the public.

tyfon 6y ago

Curious about how accurate these tests are. The recent coronavirus is just one of many in a family that also includes common cold as written in the article, "There was the potential for a false positive due to the virus’ similarities with other respiratory infections". Considering this is just one test out of many that came back positive and the next positive result was in January 2020 I suspect it's just that, a false positive. But it makes for a good headline.

deleted 6y ago

[deleted]

Izkata 6y ago

The paper itself was posted yesterday, with a lot of criticism: https://news.ycombinator.com/item?id=23652804 https://news.ycombinator.com/item?id=23652804

abathur 6y ago
Thanks for pointing to this. I missed it yesterday. A little disappointed in Reuters for the handling of this. I wish news outlets were treating direct reporting of single-study-preprint (i.e., just credulously reporting the preprint's claims with no attempt to seek expert feedback) as roughly equivalent of publishing a single-anonymous-source article without bothering to fact check. There might be circumstances where it's merited--but they'll be extraordinary, and you should probably feel compelled to explain why you think it's important enough to break the norm.
ljf 6y ago
Thanks for this - I hadn't seen that yesterday, and wouldn't have posted this otherwise. My wife has had long term post-covid symptoms and goes in a slack group to discuss and this was posted and I thought it was interesting. I'll flag this post myself.

ageitgey 6y ago

They had one partial positive test result from one random sample taken in March 2019. None of the samples taken during the following months tested positive until Jan 15, 2020. The paper is a preprint that hasn't been peer reviewed. The overwhelmingly likely explanation is one incorrect test result due to something like an imperfect test or cross contamination. You would need much better evidence than that to rewrite the entire timeline of this disease.