Biosafety in surgical pathology in the era of SARS-Cov2 pandemia. A statement of the Italian Society of Surgical Pathology and Cytology

Surgical pathology units face chemical and biological risks. While chemical risks have been intensely evaluated since the formalin ban, less attention has been drown to biological risks. The actual epidemiologic situation due to the SARS-CoV-2 pandemia has raised a series of questions, which need to be addressed as soon as possible. We have to pursue two lines of action: on one hand we must immediately adopt urgent measures to reduce the risk of SARS-CoV-2 infection of laboratory personnel, and on the other hand, we must address crucial technical and organizational aspects of biological risk reduction, preserving as much as possible the quality of tissue and cell samples. The evaluation of biological risk is an analytical process which involves different steps: a) characterization of the hazard (also known as risk assessment) and b) definition of a risk reduction strategy (also known as risk mitigation) 1. Risk assessment implies a) the identification of the intrinsic biologic characteristics of the infectious agent, and b) the identification of the laboratory procedures related to the agent. The intrinsic biologic characteristics of infectious agents are classified in 4 risk groups (RG) by the laboratory biosafety manual of the WHO 2. The RG range from level 1 (RG1) which includes microorganisms that are unlikely to cause human or animal disease, to level 4 (RG4) which includes pathogens which cause serious diseases, that can be readily transmitted from one individual to another, and for which effective treatment and preventive measures are not usually available. Risk mitigation includes the definition of the appropriate a) level of biosafety of the laboratory, b) type of personal protection equipment (PPE), c) type of infrastructure and equipment, and d) education of involved personnel. Laboratory biosafety is graded in 4 levels (BSL-1 to BSL-4) as exhaustively described in the laboratory biosafety manual of the WHO 2, and these levels are usually also defined by law (in Italy by the D. Lgs. 81/2008). BSL are a series of protections, which include individual safeguards designed to protect laboratory personnel, as well as the surrounding environment and community. The biosafety level required in laboratories derives from the characterization of the risk, and is not automatically derived from the risk group to which the pathogenic agent belongs. It is obvious that the biosafety level for a laboratory which cultivates a RG3 agent, will be higher than the level needed for a laboratory which performs diagnostic tests on inactivated biomaterials on the same agent. Specific checklists, derived from the WHO laboratory biosafety manual, which in Italy are also defined by the National Institute of Labor Safety Insurance (Istituto Nazionale Assicurazione Infortuni sul Lavoro) in its 6th Fascicle published in 2010 3 are necessary to verify the compliance of a given laboratory with the required biosafety level.