Water wash personal decontamination effectiveness to reduce biological surrogate MS2 virus aerosol risk from shaken military uniform fabric

Objective: High-volume, low-pressure water wash decontamination was used to reduce the residual viral agent that became aerosolized when fabric swatches were shaken. Design: The viral agent surrogate, bacteriophage Emesvirus zinderi (MS2), was used to contaminate swatches of military uniform fabric. MS2 was aerosolized at a 1010 plaque-forming units per milliliter (PFU/mL) concentration using a six-jet Collison nebulizer to contaminate swatches. Setting: Mass casualty decontamination of a viral aerosol agent. Participants: None. Interventions: High-volume, low-pressure water wash of contaminated fabric was compared to a control condition with no decontamination. After decontamination, MS2 particles were reaerosolized from the fabric by vibration at 50 Hz using a vortex, and an SKC BioSampler collected air samples with sterile deionized water as the collection liquid. Same-day plaque assay analyses were conducted to determine overall aerosol concentrations. Main outcome measures: Aerosolized MS2 virus was sampled in the air above shaken swatches of military uniform fabric. The samples were plated and counted using a plaque assay. Results: Student’s t-test (p = 0.0001) indicated a significant reduction in aerosolized MS2 virus when comparing no decontamination to a water wash. Results showed an average 83.5 percent reduction, which is less than a 1-log10 reduction in PFU/mL for reaerosolized MS2 after the decontamination procedure was applied. Conclusions: Viral agents can reaerosolize from military clothing fabric and present an airborne risk to patients and attending medics. A water wash significantly reduced residual aerosolized MS2 virus released from shaken fabric swatches by an average of 83.5 percent. While this is less than 1-log10 reduction, it is within the military-suggested range of 75-90 percent reduction.