With edible insects being increasingly produced, food safety authorities have called for the determination of microbiological challenges posed to human health. Here, we find that the bacterial endospore fraction in industrially reared mealworm and cricket samples is largely comprised of Bacillus cereus group members that can pose insect or human health risks. Hepatitis A virus, hepatitis E virus and norovirus genogroup II were not detected in the sample collection, indicating a low food safety risk from these viral pathogens.
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Sequencing data obtained in this study have been deposited in GenBank (National Center for Biotechnology Information) with the accession codes MN508485 to MN508527 (Supplementary Table 1). All other data that support the findings of this study are available from the corresponding author upon request.
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Virus references and IACs were provided by I. Di Bartolo from the Italian Istituto Superiore di Sanità (ISS) and N. Cook from Fera Science Ltd. We thank A. Paeleman (Scientia Terrae Research Institute) for her expertise and assistance in designing and optimizing the qPCR protocols, S. Crauwels (KU Leuven) for processing the sequencing results and R. Smets (KU Leuven) for help with the statistics. J. Franciotti, L. De Vrindt, N. Huybrechts, M. Gerits, S. Machtajiw, J. Plas and E. Van Vossole are acknowledged for their assistance in the lab. This research was financially supported by Flanders Innovation & Entrepreneurship (VLAIO) (Project 141129) as well as Internal Funds KU Leuven (grant number PDM/18/159).
The authors declare no competing interests.
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Vandeweyer, D., Lievens, B. & Van Campenhout, L. Identification of bacterial endospores and targeted detection of foodborne viruses in industrially reared insects for food. Nat Food 1, 511–516 (2020). https://doi.org/10.1038/s43016-020-0120-z