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So, of course no one in the media ever explains the process of confirmation. They’d rather just tell us how few tests are being done.

I did their job and a simple google search came up with this.

I don’t understand much of it, but it seems that the most accurate test requires a culture be grown and analyzed. The write mentioned that many labs in China, (and I presume other places including the US) were not sophisticated enough to perform this test.

There’s another shorter term test, but it seems to be very inaccurate.

Here it is:

There are actually 3+ types of test kits widely used to diagnose diseases caused by viruses. We can check for the nucleic acid of the virus, the antigen of the virus that would cause an immune response or the antibody produced during the immune response of the patient. Since we’ve already got the whole sequence of the nCoV, the test kits normally used this time (at least in China) fall into the nucleic acid class.
To diagnose a patient with this type of test kit, the patient’s nasopharyngeal swab, sputum or alveolar lavage fluid would firstly be collected to get a sample of the virus. Some reagents would then be used to extract the nucleic acid in it. After a reverse-transcription which would produce a DNA sequence based on the original single-stranded RNA gene of the virus, a PCR would be performed to amplify it to a large enough amount to eliminate the interference of other genetic materials in the sample (e.g. human DNA, genes of some normally existing bacteria and/or viruses). Here is where the nucleic acid detection kit would take place: the kit contains several characteristic genes serving as a guideline of the PCR, and it would have two primers that flank the target regions for each gene. The kit would also check if the amplification process goes well: it contains fluorescence molecules whose intensity would increase exponentially with the number of amplification (if target fragment exists in the original sample). The whole set of the testing process is called qPCR (quantitative polymerase chain reaction, or real-time polymerase chain reaction) and it requires highly precise thermal control and real-time fluorescence measurement. The labs where those qPCR instruments are in also need to be high-standard cleanrooms with negative air pressure in order to ensure that samples would not be contaminated by previously amplified DNA products. Unfortunately, most hospital labs in China are not qualified enough to perform tests of this level and that’s why it takes so long to truly diagnose a patient with nCoV, even if tons of test kits are already sent to the infected area.
Recently a new method called POCT rapid detection is being tested and it is said that it takes only 15 min to get the result. This method takes a colloidal gold-based immunochromatographic assay to detect the nCoV antibody produced by the patient. Going through the strip, the material tested would pass through a layer of the colloidal gold marker that binds to the antibody, a detection line that contains the corresponding antigen, and a control line that would change colour once it detects any liquid that contains the colloidal gold. This method feels kind of like a pregnancy test, where two lines are bad (i.e. antibodies is detected in the sample as they bind with antigens) and one line is good. It’s much faster than the nucleic acid test and it’s easier to apply, but the problem is that you can get false positives or false negatives due to the different amounts of antibodies produced by patients. It can be used as a supplementary method for nucleic acid detection, but for clinical use we may want to be more careful with it.

https://biology.stackexchange.com/questions/90095/how-does-a-coronavirus-test-kit-work