Comment by bionhoward | Hacker News Reader

Comment by bionhoward | Hacker News Reader

Looks great until they hit the ELISA (antibody test) which requires pre-existing antibodies for the target. That’s like when you search for your keys under the streetlight when you dropped them in the dark. Anything novel becomes an expensive and slow ordeal (aka, it doesn’t happen in practical use) because you need “test kits” (sound familiar?) ... just imagine your malware detector would only flag code which exactly matched exploits it had seen already.

If they replace ELISA with a nanopore sequencer like Oxford’s MinION then you could detect all the DNA RNA in your breath and feed that data into algorithms like BLASTN. Suddenly you can see viruses no one ever saw, and thousands of them at once. Meta genomics is more sensitive than ELISA because you can see everything and more efficient because you can use the same reagents to test for anything. Then we detect virus everywhere as soon as the sequence is available on NCBI (we had a sequence for CoV-19 two months & four days ago)

https://www.who.int/csr/don/12-january-2020-novel-coronaviru...

I don't know the technical details of MinION.

Coupling good capture with amplification and detection is required. When working on dna detection you use something like pcr for signal amplification.

But surface detection can in some cases be more sensitive, since you generally have a lot more surface fragments available than you have dna or rna. Especially since many viral diseases form have huge ratios of surface fragments per every well formed infectious viral particle.

Generally: a sequencer by itself doesn't have the sensitivity required. For example, for norovirus we're talking about detecting a few virus particles per cubic meter of air. You need insanely sensitive detection tech to be able to do that.

> I don't know the technical details of MinION.

Neither does OP.

Naive question, because I only knew of ELISA. but can you use MinION or something like it to detect DNA/RNA in blood?

I would be excited if this was cost effective and more sensitive and specific for bacteria and viruses than what we have currently.

With all things RNA related, sample prep and PCR amplification are the most important steps for good detection with any sequencing platform.

Those factors alone make sequencing alone a near impossibility in rapid detection. PCR based assays are a much better candidate and could identify different strains in less than a few hours.

This is very interesting. I'm usually on the side of interpreting tests/ordering them instead of knowing the nuances behind them. Are there any major breakthroughs in testing that you're excited about?

Your first concern is a problem in the current situation, but wouldn't this be immensely helpful in avoiding/preparing for a second wave in the fall (if weather has any impact) or next year (if it becomes pandemic and endemic)?

There are other ways to build ultra sensitive assay technology that does not depend on antibodies, and which can be faster to develop.

how cost effective is your solution ?

The 'starter pack' costs $1,000, which is good for just two uses.

However, the entire device is just made of plastic, silicon and metal, which are very cheap materials. The majority of the cost is R&D cost, which if one were to produce millions of this device would be amortized and you could bring the cost down to that of a $10 fake ink cartridge, which coincidentally has awfully similar technology.

One would think the case for further public investment in such R&D is now made.

note this is from 2018, so it makes drop in like MinION or other sequencers even more feasible

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