https://doi.org/10.17113/ftb.61.02.23.8018

Supplement

Investigation of SARS-CoV-2 Detection Method Applicability and Virus Occurrence in Food and Food Packaging

Zdenko Mlinar^1*, Deni Kostelac², Ivančica Kovaček¹, Ana Klobučar¹, Vanja Tešić^1,3, Vedran Prahin¹ and Jadranka Frece²

¹Andrija Štampar Teaching Institute of Public Health, Mirogojska cesta 16, 10000 Zagreb, Croatia

²Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva ulica 6, 10000 Zagreb, Croatia

³Faculty of Medicine, University of Rijeka, Braće Branchetta 20, 51 000 Rijeka, Croatia

Article history:

Received: 30 November 2022

Accepted: 13 June 2023

Keywords:

SARS-CoV-2; food; RT-PCR; coronavirus; foodborne transmission; RNA extraction

Summary:

Research background. While it is clear that SARS CoV-2 coronavirus is the primary respiratory virus, there are no entirely clarified ways of transmission. Foodborne transmission has remained an unexplained path. Therefore, the goals of this paper are to examine and present an assessment of the most appropriate of the four selected kits for RNA extraction for the testing and detection of SARS-CoV-2 on food packaging surfaces, food surfaces, and in food. This will enable to indicate the possibility of infection through contact or direct food consumption.

Experimental approach. Finding the best technique is vital as RNA extraction is one of the essential elements in detecting SARS-CoV-2. This was achieved through an experiment with four commercial kits following the original manufacturers’ protocols, and with a modification of the original protocols that included the use of ethanol and isopropanol. The selected kit was used for RNA extraction from the swabs of packaging surfaces, food surface, and ready-to-eat food samples. The coronavirus was then identified using real-time reverse transcription-polymerase chain reaction (RT-PCR) assays to determine whether the SARS-CoV-2 virus or viral particles are present in the food chain with the overall purpose of demonstrating the possibility that food can contribute as a vehicle for the transmission of the virus.

Results and conclusions. The findings of this investigation made the most effective extraction kit and protocol stand out. The results of the applicability of the kit indicated a significant share of positive samples of viral SARS-CoV-2 virus particles on surfaces from the environment where infected persons with ‘silent’ COVID-19 infection, with mild symptoms or no symptoms, were present. However, according to the findings of the second part of the study, the virus was not detected on the examined samples of food packaging surfaces, food surfaces, and food.

Novelty and scientific contribution. The presented results distinguished one of the most suitable protocols for isolating RNA from environmental surface samples. The main contribution of the study is in the presentation of the results, that is, the examination of samples that are primarily related to the food chain, food packaging, food surfaces, and ready-to-eat food. The results of this study could also be helpful for further determination of the potential of food as a vector for the transmission of coronaviruses.