Question

4) Testing for infection with the novel coronavirus Covid-19 is much in the news lately. The coronavirus is related to other similar viruses that already circulate in the US population, causing common cold symptoms. The RNA genomes of these viruses thus share substantial sequence identity. Describe how you might develop a molecular diagnostic that will distinguish the novel coronavirus from previously circulation coronaviruses. Discuss the potential problems that could occur with a diagnostic procedure that could lead to misleading or false results.

Answer 1

Covid-19 can be diagnosed by using an rRT-PCR assay developed by CDC. For this rRT-PCR, we collect multiple specimens, including lower and upper respiratory samples, serum, and stool specimens. Here we consider a person under investigation to be negative for active MERS-CoV infection following one negative rRT-PCR test on the recommended specimens. Since a single result can not completely end the CoV infection, in some circumstances additional specimens may be tested. Also, we consider a known Covid-19 patient to be negative for active Covid-19 infection following two consecutive negative rRT-PCR tests on all specimens.