Certainly a possibility, but I would think that it would very unlikely to contaminate the source sample (usually they're frozen in -80 fridge), and if you have a contaminated work station, then the rest of the samples would likely be return false-positive as well.
Could easily be "mixed samples" on the other end instead of intentional leaks. You know how old lab equipment could be really useful in a live seafood market.
I understand their concern; however I don't agree that the remedy mentioned in the article is the only path.
Knowing a sample is rendered invalid by mishandling or age might be accomplished by packaging an indicator with it which reacts when exposed to extreme temperatures and/or a chemical timer once packed.
The samples could also be delivered via drop-off to collection stations at hub facilities (E.G. medical clinics or hospitals) and stored in controlled environments for the rest of the process.
My claim wasn't that "the team(s) involved did not consider that contamination could occur before or after the sample was obtained and analyzed".
I merely gave a trivial (even exhaustive!) enumeration of possible contamination cases that could still have happened (regardless of whether they are targeted against in their protocols), not some novel avenue for contamination that I claim to be "smarter than the scientists" to come up with.
Of course they knew of those contamination possibilities. I didn't say anything about them having missed such basic contamination cases.
What I did (and am) suggesting is that they probably are too confident in their protocols having been executed correctly and being 100% tight with no possibility of error. And that that those avenues of contamination are still a real possibility (protocols to prevent them be damned).
Now, this might not be the case. This might indeed be space travelling RNA-combound and B3 vitamin.
But I'd say that the probability of contamination being the case and someone (on HN or wherever) calling it correctly, is equal to the probability of the samples being contaminated. Which is not that small.
Spotting some novel contamination route they haven't thought off would indeed be very rare and a major feat. But merely been less confident (that they are) in their thoroughness and in their preclusion of contamination, is much easier to claim and be correct while doing so.
That's one of the things they were doing, but the other machines they were using weren't designed or tested to use diluted samples. At least the sensitivity of the test would suffer, but really it's out of spec and so unknown.
If you want CLIA lab certification, there are a number of rules surrounding cross contamination, which not sealing a plate of samples properly might be a red flag.
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