The Plume Room - adventures in toilet hygiene

Infection Control Matters

In this episode recorded in an Irish Bar in Nelson (NZ), Brett and Martin dive headfirst into the swirling world of toilet aerosols, airborne pathogens, and potential mitigations.
We begin with a older study by Scott, Bloomfield, and Barlow examining the effectiveness of disinfection in real-world settings and how this depends heavily on practical application and behavioural compliance. Then we move to move to a recent contribution by Higham and colleagues, who shift the focus from surface disinfection to airborne exposure. Their paper presents a quantitative microbial risk assessment framework that models aerosolised viral particles generated by toilet flushing that demonstrates the importance of ventilation. Finally we discuss the work of Boone and colleagues, who evaluate a practical intervention—an air sanitizer spray—and its impact on reducing airborne virus concentrations following flushing events.

Papers that we discuss:

Scott E, Bloomfield SF, Barlow CG. Evaluation of disinfectants in the domestic environment under 'in use' conditions. J Hyg (Lond) 1984;92(2):193-203. https://doi.org/10.1017/s0022172400064214

Higham CA, López-García M, Noakes CJ, Tidswell E, Fletcher L. A Quantitative Microbial Risk Assessment (QMRA) framework for exposure from toilet flushing using experimental aerosol concentration measurements. Indoor Environments 2025;2(1). https://doi.org/10.1016/j.indenv.2024.100069

Boone SA, Betts-Childress ND, Ijaz MK, McKinney J, Gerba CP. The impact of an air sanitizer spray on the risk of virus transmission by aerosols generated by toilet flushing. Am J Infect Control 2025. https://doi.org/10.1016/j.ajic.2025.04.008