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Comparative Analysis of the Fourth and Fifth Editions of Biosafety in Microbiological and Biomedical Laboratories Section IV (BSL2-4)

We developed a matrix of changes between Section IV of the current and former editions of Biosafety in Microbiological and Biomedical Laboratories (BMBL), focusing on biosafety levels two, three, and four (BSL2, BSL3, and BSL4). Citations containing multiple statements were subdivided into individually addressable statements and statements with similar/identical scope were aligned, allowing for a precise comparative analysis. In addition, statements were categorized for further analysis based on the subject of the change, the type of change, and the outcome of the change. Although the Fifth Edition of BMBL (BMBL5) proved to be a close facsimile of its predecessor, we identified 375 total changes, including 165 novel statements not addressed in the former edition. Over 65% (110) of these changes were found in statements pertaining to BSL4 containment. In our study, we further examine these edition differences and identify key areas where those entities responsible for compliance with these new recommendations may wish to focus their efforts.