That’s the test that Michael Mina has been talking about on TWIV and elsewhere, and he claims it’s possible right now. He says, however, that the FDA wouldn’t approve it, because a test that’s not as accurate as a PCR test—but that accurately detects people who are infectious—couldn’t get FDA approval. That’s a perverse situation. From a public health perspective, the only people we want to identify are people who could spread the disease.
Does it work on those machines that doctors offices have to test for flu?
No, it has to go to a lab. It will be interesting to see how many labs provide and commercialize the SalivaDirect test.
If it’s cheaper and faster and they can use their existing stuff, I forsee alot. This could be a big help for returning our elementary students back to the classroom.
Margins will have to be there unless it’s a government or philanthropic organization commercializing it.
Not sure the turn around is fast enough to change things for k-8 schools…for example, in Illinois, one positive test requires each of that kid’s classmates (in some schools where each kid goes to multiple classes with different students that could be a lot of kids) and teachers to quarantine for 14 days. This test won’t change that.
Edited to add: It seems like we need the rapid strip test (like Michael Mina’s discusses) to help with the school, and office workplace, issues.
We need the rapid strip test and it has to happen at the federal level.
An article a couple of pages back said the Yale test requires that labs have an expensive piece of equipment to process them. I don’t see how the cost can be ~$4/person unless they already own that piece of technology. Plus, they have to receive certification. It doesn’t say how long that process takes.
The FDA authorization says, “Because this test does not rely on any proprietary equipment from Yale and can use a variety of commercially available testing components, it can be assembled and used in high-complexity labs throughout the country, provided they comply with the conditions of authorization in the EUA.”
Because of this comment, as well as what else I’ve read, I believe that a high-complexity lab would already have the equipment needed to process the test.
On a side note, for those of you who are interested in how the pandemic got started, here is some interesting reading:
“A Proposed Origin for SARS-CoV-2 and the COVID-19 Pandemic” by Jonathan Latham, PhD and Allison Wilson, PhD
It is on the Independent Science News website.
It presents a theory I had not heard of before based on the Masters Degree thesis of a Chinese student. No need to look at pangolins anymore.
Oh please…I prefer medical news from respected sources.
The “mystery” that the Independent Science paper attempts to explain is why this bat virus moved to another animal and mutated a spike protein to target the ACE2 receptor in humans. But a paper discussed on This Week in Virology (TWIV) 648 addresses this very issue. And it turns out that the the virus didn’t hop to another intermediate species (like pangolins) and then mutate to have the spike protein. The virus had the spike protein all along! Some coronaviruses in bats have the spike protein.
Here’s the paper, which was published in Nature Microbiology: https://www.nature.com/articles/s41564-020-0771-4
And here’s TWIV. You want Episode 648: https://www.microbe.tv/twiv/
Last year at this time I didn’t think I’d become a listener to This Week in Virology. Who had heard of that obscure recherche podcast?
The story, as also reported in Newsweek (7/6/20), is that 6 miners in Yunnan Province got a coronavirus-like illness in 2012 after clearing bat guano from a mine. Three of them died. They had symptoms such as dry cough, fever, low oxygen levels, and blood clots. Blood samples from the miners were sent to the lab in Wuhan. This information seems to point to direct transmission from horseshoe bats to humans. It also seems to show that China knew this information and covered it up by claiming that the miners died of a fungal type illness.
I’m not convinced that the Yale Saliva Direct test is a game changer.
Pros:
No need for nasal swabs.
No need for PPE for the person who does the swabbing (not a big plus since people can swab themselves).
No need for viral media to transport the sample (virus is stable in saliva).
No need for special container to collect saliva, any sterile container will do.
No need for the reagents used to extract RNA (the test skips this step).
Cons:
Requires a high complexity lab with CLIA approval to perform.
Still requires reagents, materials, instruments, primers and probes.
Performing the test must be done by hand in several steps, by trained personnel.
Due to the above points, this test may not be any cheaper than doing PCR of nasal material by hand, and it’s slower/less safe than PCR by machine.
I’m not in the field, but from everything I’ve learned, I suspect this test will be subject to many of the same shortages and delays as the existing PCR tests. It’s basically PCR with saliva instead of nasal material, and I don’t see why it would be much cheaper or faster than the tests these labs are already performing.
Saliva is a good idea, but we need the sample to be processed on site, as rapidly and inexpensively as possible. Processing by machine/device is better than in a lab, and automatic processing (as with lateral flow technology, like a pregnancy dipstick) would be ideal.
FDA’s Medical Device shortage list:
Interesting…they specifically said it can be done for $10. Are they giving misinformation?
Labs have to commercialize it and can charge whatever they want. They have to cover the costs of the kits, transporting the sample, running the test, etc. I’m thinking that will be more than $10 and take well over 3 hours to receive IRL.
I agree with the pros and cons above…many of the factors that are slowing things down in the testing world will affect this process too.
Michael Mina has a great twitter thread on why the Yale test will not be a panacea. Like he says, we need the rapid strip test…with immediate results.
Not deliberately. But their field is research science, not medicine or lab diagnostics.
DH got tested last week in Missouri. They did both a nasal swab and a saliva test, said they were comparing the results to see how accurate the saliva test was.
Quest just reported that they are “caught up” on testing and the article also mentioned this saliva direct as a benefit.
The SalivaDirect test got emergency use authorization on Saturday, so I don’t think it contributed to Quest’s announcement (on Monday) that they have cut their turnaround time. The shortened time was attributed to a faster method of RNA extraction which was approved by the FDA on 7/29.
It is great news that it’s taking 1-2 days instead of 7+ to get results from Quest. I still maintain that NAAT (nucleic acid amplification testing) is best used for diagnostic purposes during individual patient care. For wide-scale screening purposes, we need a cheap, fast, low-tech test.