It can probably be tested by taking a bodily fluid sample and looking at it through an electron microscope. Plenty of color pics of the little bugger on the web. Not everyone has an electron scope though and it’s subject to human error/interpretation. Hence they need test kits for dummies. Why the first batch were defective? Who knows. Made in China? Procured by some RESIST person in fedgov? Incompetence on someone’s part?
Meanwhile Trump shut off travel of people coming here from China early this month and since 77,000+ cases out of 80,000 cases are in China, that seems to have given us time for the test kit glitch.
But this ain’t the flu. All we can do is keep track and prepare ourselves. So glad I moved from Ctrl FL to rural Ozarks.
After morphology, there is physiology. What media does it like, what metabolites does it produce? What temperatures does it like? Going deeper, there is the antigen signature. Use of labeled antibodies that latch onto a known antigen target can confirm a serotype.
The level of examination required for this corona virus requires breaking up the encapsulation and getting to the RNA inside. You have to amplify the tiny amount present with a polymerase chain reaction to make a huge number of identical copies. At that point you have the means to start sequencing the RNA an comparing the sequences to databases of known viruses or organisms. All of that finery was invented well after I graduated from UCSD in 1976. We did sequencing the hard way. Machines do that today.
It's not a simple process. Perhaps that's why CDC has ONE bench available and takes 6 hours to complete one test.