Inactivation of infectious virus samples through UV irradiation for downstream analysis

Abstract

Downstream analysis of infectious samples often needs to be performed outside a containment area, requiring prior inactivation before transfer. The inactivation of adenovirus, reovirus, and rabies virus by ultraviolet radiation at 254 nm (UV-C) was investigated with the objective of preserving the bacterial endotoxin test (BET) performance in irradiated samples. Virus samples containing endotoxins were exposed to UV-C doses ranging from 1 to 9 J/cm². A treatment of 5 J/cm² (2 × 2.5 J/cm²) applied to 1 mL volumes resulted in complete viral inactivation and acceptable endotoxin recovery. Samples containing cell culture media required 10-fold dilution prior to UV irradiation to overcome UV light attenuation and achieve complete virus inactivation. UV radiation had minimal impact on endotoxins, with recovery rates around 100 % compared to non-irradiated controls, regardless of UV dose and sample volume. The development of optimized UV-C irradiation conditions enabled the identification of a dose interval that ensures effective viral inactivation while maintaining BET specificity and applicability. The irradiation process is intended for industrial implementation on rabies vaccine samples, allowing testing outside containment areas and ensuring that biological samples are safely inactivated, without residual biological risk.