Exploring Surrogate Selection for Virucidal Aerosol Testing: A Qualitative Analysis

The COVID-19 pandemic heightened interest in the development
and
testing of virucidal chemistries and technologies for use in indoor
environments. Direct testing of pathogens often requires a high-level
biosafety containment, which can restrict performance evaluations
to smaller scales that may have limited translatability to the complexities
of real-world indoor environments. Therefore, using viral surrogates
that are safer to work with than target pathogens offers many potential
benefits, including aerosol testing in more realistic conditions.
This scoping review analyzes surrogate selection and use across aerosol,
surface, and suspension-based tests and identifies bridges in surrogate
selection considerations. A qualitative analysis of 133 studies was
conducted to highlight trends, knowledge gaps, and future directions
toward standardized surrogate selection frameworks. This review finds
that Enterobacteria phage MS2 (MS2) and other bacteriophages
are commonly used due to their practicality and safety. There are
limited examples of concurrent pathogen and surrogate testing to assess
suitability, which is highly context-dependent on the test conditions.
Beyond virucide testing, the surrogate selection considerations discussed
herein are informative for research on the persistence, transmission,
transport, behavior, and nonchemical management of airborne viruses.