testing is the critical way of confirming the presence of sars-cov-2 virus for those suspected of being infected or in contact with a known case, and since canadians won’t be fully vaccinated until very late this year, testing remains critical.
there is increasing need for exclusionary testing for symptoms, contact tracing for those infected, travel mandates as well as testing at some workplaces. this makes it important to know what tests are available and how accurate in determining covid-19 infection.
there is also some debate in conspiracy circles as to whether current tests purposely overestimate disease levels due to the belief that so much asymptomatic disease can’t really be a “disease,” but rather, must be due to false positive testing.
there are two types of tests to understand, namely molecular and antigen-based and they either require being sent to a large laboratory for overnight analysis, or can be analyzed at the point of care or at home.
molecular tests for sars-cov-2 using pcr and their accuracy
these tests are the gold standard, and the most sensitive. they detect viral molecular genetic material by amplifying the amount of virus obtained from a deeply inserted nasal swab. the test detects single strand viral rna (what the virus is made of) and then converts it into double strand dna, cuts a piece with a probe and then amplifies it through polymerase chain reaction (pcr).