Probiotic-Based Sanitation in the Built Environment—An Alternative to Chemical Disinfectants

The use of conventional chemical disinfectants is a common practice in built environments and has drastically increased in response to the COVID-19 pandemic. While effective for instantaneous disinfection, the application of chemical disinfectants to indoor surfaces is associated with recontamination and is prone to select for antimicrobial-resistant pathogens. In contrast, probiotic-based sanitation (PBS) relies on the premise that probiotic bacteria, namely apathogenic Bacillus spp., when combined with eco-friendly detergents and applied to indoor surfaces can outcompete and exclude pathogens. Recent in situ studies assessing PBS in healthcare settings have demonstrated overwhelmingly positive results, including significant reductions in pathogen burden, antimicrobial-resistant genes and nosocomial infections, yet these studies are limited in duration and scope. Here, we review results of Bacillus-based PBS in practice, identify knowledge gaps and discuss the considerations for the widespread use of PBS in built environments. In a time when indoor cleaning and disinfection has come to the forefront, PBS may offer an attractive, effective and sustainable alternative to conventional chemical disinfectants.