Real time RT-PCR is a nuclear-derived method for detecting the presence of specific genetic material from any pathogen, including a virus. Originally, the method used radioactive isotope markers to detect targeted genetic materials, but subsequent refining has led to the replacement of the isotopic labelling with special markers, most frequently fluorescent dyes. With this technique, scientists can see the results almost immediately while the process is still ongoing; conventional RT-PCR only provides results at the end.
While real time RT-PCR is now the most widely used method for detecting coronaviruses, many countries still need support in setting up and using the technique.
https://www.iaea.org/newscenter/news/how-is-the-covid-19-virus-detected-using-real-time-rt-pcr
