A primary study of the thermal stability and inactivation of severe fever with thrombocytopenia syndrome virus

Abstract

Objective To elucidate the thermal stability and inactivation of severe fever with thrombocytopenia syndrome virus (SFTSV).Methods The stability of cell culture-derived SFTSV (SD4 strain) under different environmental temperatures,and the ability of heat,ultraviolet rays,diethyl ether,chloroform,acid,disinfectants treatments to inactivate SFTSV were evaluated.The infectious titers of treated viral samples were determined by titration assay based on a double N protein specific antibodies sandwich ELISA assay for SFTSV in Vero cells.An indirect immunofluorescence assay was performed to determine the replication dynamic of SFTSV in cells.Results SFTSV in culture medium was relatively stable at 4℃ without drastic loss of infectivity for at least 1 week,and the virus was sensitive to heat and could be inactivated in 30 min when incubated at 60℃.UV light irradiation with an intensity of 185 μW/cm2 efficiently inactivated SFTSV within 30 min.Exposures to optimized concentration of diethyl ether,chloroform,β-propionolactone,formaldehyde,Hypochlorous acid all destroyed SFTSV infectivity effectively.Acid conditions brought damage to the virus activity,but virus could not be completely inactivated at pH3.0.Conclusion The results provide quantitative evidence for the potential use of a variety of approaches for samples collection,inactivating SFTSV,and safety protection in scientific research and diseases control and prevention. Key words: Phlebovirus; Thrombocytopenia; Heat stress disorders; Inactivation