Scientific evidence links COVID-19 transmission with fecal aerosols. A recent study, published in Annals of Internal Medicine, explored an outbreak in a high-rise apartment building in Guangzhou, China. The outbreak infected 9 individuals living in different units throughout the building. Through patient interviews, throat swabs, and an in-depth environmental investigation, researchers found that transmission most likely occurred in the master bathrooms of the apartments, which were connected through drainage vents. Fecal bio-aerosols most likely leaked, travelling from one apartment to another through the bathroom drainage pipes. Annals of Internal Medicine

Takeaway: To prevent future outbreaks of this kind, scientists who conducted the study recommend immediately resolving any leaks that exist within sewage drainage systems. This will prevent bio-aerosols from escaping and becoming a hazard. The findings in this study add to the growing evidence that COVID-19 and other infectious diseases can be spread through wastewater plumbing systems, especially those in high-rise buildings.  

Studies also show that fecal aerosols can be dispersed into the air during flushing, referred to as “toilet plume”, which can potentially transmit COVID-19 to others in the bathroom during the flush, as well as those entering the bathroom at a later time. Small bathrooms and those with poor ventilation are the most at risk for fecal aerosols.