COVID spit test is faster, cheaper, avoids shortages?and now greenlit by FDA

Generally, these tests determine if a person is currently infected with the pandemic coronavirus, SARS-CoV-2, by detecting the genetic material of SARS-CoV-2, which is in the form of RNA rather than DNA.The basic steps of the test start with sticking a long swab far into a person’s nose until it hits the back—a nasopharyngeal swap—to try to scrape up any SARS-CoV-2 that may be present. If it’s above, say 37, it means there was little SARS-CoV-2 RNA in the sample, perhaps from a fading infection or genetic remnants of a recently ended infection.For diagnostic tests, the Ct value isn’t necessarily useful—if you have any amount of SARS-CoV-2 RNA in your nose, you are or were very recently infected. They took saliva and nasal swabs from 37 known-positive patients and ran a standard lab test for SARS-CoV-2 on all the samples. Last, the researchers streamlined the RT-qPCR by combining a few steps and still saw similar Ct values.In a head-to-head comparison with dozens of positive samples from infected people, SalivaDirect results were the same as standard nasal test results 94 percent of the time. Comparing SalivaDirect to standard lab tests on saliva, the tests agreed 97 percent of the time for positive samples and 100 percent on negative samples.