The difference between a research and a clinical test is how the performance characteristics must be understood clinically. If you’re going to screen 1000s of patients, and use the results to clear negative patients, you have to understand how often you’ll get it wrong 2/18
In this case, we should be very concerned with the sensitivity of the test (false negative rate). If it’s even as low as 90% that’s potentially thousands of people who have the virus sent back into their communities. 3/18
The process of understanding the performance of your test is called validation. It is supervised by #pathologists (in this case, #molecularpathologists or #clinicalmicrobiologists) who have specific training and clinical understanding of the consequences. 4/18
It takes weeks under optimal circumstances, but it has to be done, and it has to be handled by a medical professional. 5/18
You may have heard the term lab-developed test or “LDT.” This term means the lab decided which components to use and conducted a validation. It DOES NOT mean the lab invented a brand new test from whole cloth. LDTs are integral, normal components of everyday clinical labs. 6/18
2) true: the supply chain is inadequate for our current needs. Testing components and reagents need to be manufactured and some have a shelf-life. During emergencies, the supply is exhausted quickly. This has downstream consequences on many other tests for DNA/RNA. 7/18
This is not a failure of industry, but a consequence of relying on markets. The market doesn’t anticipate disasters. It doesn’t anticipate anything. It was the job of government to account for emergencies, and it repeatedly ignored expert warnings. 8/18
3) The FDA has insisted that it has authority to regulate clinical tests, despite that FDA was intended and designed to regulate the safe manufacture of drugs and medical devices, which operate under different principles. 9/18
Lab testing is already regulated, and has been for decades, by a law called CLIA. CLIA is admittedly imperfect, but has the advantage of being designed for the purpose of lab testing. 10/18
Perhaps the most important distinction is this: lab tests are overseen and administered by licensed medical professionals. The manufacture of drugs and devices is not. By extending its remit to include LDTs, FDA has interfered with the practice of medicine. 11/18
We see the consequences of that interference during the current crisis. Local testing could have begun development and validation weeks ago, but instead had to wait for approval. 12/18
Just compare the swift and professional lab response in the 2009 H1N1 flu outbreak (when FDA chose not to intervene in lab testing) to today. 13/18
Please note that these are bureaucratic decisions, the timing of which may fall during one administration or another, but have little to do with politics, and everything to do with protecting a perceived authority. 14/18
4) what can be done? If you work in a non-clinical lab doing DNA/RNA testing, please preserve reagents and kits related to extraction. These are precious right now. 15/18
If you can find a way to donate unused reagents to a local clinical or industrial lab that has active #Covid_19 testing, that’s great, but they are tragically few right now, and they may not need exactly what you have. 16/18
As testing ramps up over the next couple of weeks, if you have experience in a modern clinical or research lab (especially current grad students), consider reaching out to your local clinical lab to volunteer.17/18
We generally do not need help with assay development, but we may need assistance scaling up the volume of testing. 18/18
