The main difference between the tests and the widely used PCR test is that they do not require the extraction of RNA from the virus, which is both difficult and time-consuming. At the same time, they are much more accurate than express antibody tests, which only respond to a very high viral load. The first test was called the antisense test, which detects the presence of the virus in a smear sample using an innovative technology called electrochemical sensing. The prototype test looks like a glucose meter, so it can easily be used at home. Antisense has already been approved by the FDA and is now in the last stage of testing, which shows it to be 98 % accurate. This is comparable to a PCR assay. The second test also doesn't require access to a lab or sophisticated equipment. It uses a highly specific molecule attached to gold nanoparticles to detect a protein. This protein is part of a genetic sequence unique to the [COVID-19](https://ul.orna.me/KOge/librarydisease?id=221) virus. When the virus is detected, the gold nanoparticles change the color of the liquid reagent from purple to blue. Preliminary tests of the test system showed that it can detect the virus on the first day of infection. According to the authors of the study, rapid and highly accurate tests will dramatically reduce the spread of COVID-19, including new strains. __Source__: https://www.nature.com/articles/s41596-021-00546-w