Evaluation of the persistence of SARS-CoV-2 (ATCC® VR-1986HK™) on two different food contact materials: flow pack polyethylene and polystyrene food trays

Abstract

Even though SARS-CoV-2’s primary transmission pathway is person-to-person, the role played by surfaces and food contact materials in carrying viral RNA should be further explored. For this purpose, the study aimed to investigate the persistence of SARS-CoV-2 using the strain ATCC® VR-1986HK™ on flow pack polyethylene (FPP) and polystyrene food trays (PFT). Samples of FPP and PFT were contaminated with heat-inactivated SARS-CoV-2 and were incubated at a temperature of 24 ± 1°C and at controlled relative humidity (RH 65%). The experimental design included analyses at the time 0, 3, 6, 12, 24, 36, 48 and after every 24 hours until the viral RNA was no longer detectable. The results showed a significant decrease ( P <0.001) in viral copies number on PFT within 3 hours (24% reduction) and, at 72 hours, the viral RNA had fallen below the limit of detection. Regarding the FPP, it was necessary to wait 24 hours for a significant decrease ( P =0.015) in the viral load (14% reduction), while the detection threshold was reached at 96 hours. These findings showed that the viral RNA persists longer on polyethylene flow pack samples than on polystyrene food trays, thus highlighting the importance of material characteristics in the persistence of SARS-CoV-2.

Survival of human coronavirus 229E at different temperatures on various food-contact surfaces and food and under simulated digestive conditions

“…Moisture evaporation and drying occur more easily on porous surfaces ( Chatterjee et al, 2021 ). Also, virus recovery from porous surfaces is lower than from non-porous surfaces because of absorption of virus ( Castrica et al, 2021 , Terio et al, 2021 ). Therefore, survivability of virus on porous surfaces may be lower than on non-porous and non-porous surfaces may be better carriers of SARS-CoV-2 transmission.…”