Can Flushing of Domestic and Public Toilet Spread SARS-Cov-2 and Other Enteric Pathogens?

Microbial transmission has been studied extensively during the SARS-CoV-2 pandemic of the last four years. A new way of transmission of enveloped viruses has been suggested, that is infectious aerosols escaping the toilet after flushing, which if true would have serious health consequences. Corona viruses reach the alimentary canal in a similar manner to parasites in that their life cycle includes the lung from where they are coughed and then swallowed. Many pathogens, bacterial and parasites, can survive the harsh environment of the stomach, however very few enveloped viruses, such as Corona and Hepatitis B can survive, thus the probability of their transmission within the toilet environment, even though unlike bacteria and parasites there is no evidence that they can multiply in the intestines, is justifiable. This study used simple routine Microbiological monitoring methods; settle plates and stains, to determine whether microbe or stain containing aerosols detected within the toilet environment escaped from the bowl or the cistern of the toilet after flushing, when the lid was kept open. Many different bacteria and fungi were detected, which were both in numbers and types very similar to those recovered prior to flushing, however no bacteria originated from the toilet bowl and when stain was added to the bowl and cistern all aerosols detected originated from the cistern. In conclusion wash-down low pressure modern gravity-flash toilets do not pose any health threat when the toilet is flushed with the lid open.