Inactivation of Hantaan Virus-Containing Samples for Subsequent Investigations outside Biosafety Level 3 Facilities

OBJECTIVES: The potential risk of accidental infection by hantaviruses in a clinical or research laboratory necessitates special precautionary measures. A biosafety program must address handling and disposal of infectious materials as well as appropriate virus inactivation or depletion procedures to permit necessary further processing of specimens outside the biosafety level 3 laboratory. METHODS: To study the elimination of hantavirus infectivity, the effects of different chemical and physical inactivation and depletion procedures were investigated on Hantaan virus-containing materials. An infectivity assay for hantaviruses was utilised to verify these procedures which are commonly preceding investigations such as ELISA, flow cytometry analysis, Western blot or immunofluorescence assay. RESULTS: Chemical inactivation with methanol, paraformaldehyde, acetone/methanol and detergent-containing lysis buffer as well as physical forces such as UV irradiation and filtration efficiently reduced viral infectivity in infected cells and their supernatants below the detection limit. CONCLUSION: The virus inactivation and depletion methods described herein are suitable to prepare non-infectious samples for further use in immunological, virological and cell-biological assays.