Types of Transport Systems Suitable for Test of COVID-19 The formula contains special ingredients to maintain and store viruses for a longer time. It helps viruses to maintain its viability. Flocked Swab Suitable for Sample Collection of Different Types of Virus Specimens Flocked swab can uptake and release sample into liquid medium better than rayon swab. Room Temperature Storage up to 96 Hours Good Virus vitality and infectivity after stored under room temperature 96 hours