Concept
A toilet plume is the dispersal of microscopic particles as a result of flushing a toilet. Normal use of a toilet by healthy individuals is considered unlikely to be a major health risk. However this dynamic changes if an individual is fighting an illness and currently shedding out a virulent pathogen in their urine, feces or vomitus. There is indirect evidence that specific pathogens such as norovirus or SARS coronavirus could potentially be spread by toilet aerosols, but , no direct experimental studies had clearly demonstrated or refuted actual disease transmission from toilet aerosols. It has been hypothesized that dispersal of pathogens may be reduced by closing the toilet lid before flushing, and by using toilets with lower flush energy. There is indirect evidence that toilet aerosol can be a vector for diseases that involve acute gastroenteritis with the shedding of large numbers of pathogens through feces and vomit, with normal use of a toilet unlikely to be a major health risk. For example, some epidemiological studies indicate transmission of norovirus in passenger airplanes and ships, and SARS coronavirus through a contaminated building sewage system, via contaminated toilets rather than other routes. The feces and vomit of infected people can contain high concentrations of pathogens, many of which are known to survive on surfaces for weeks or months, and toilets may continue to produce contaminated toilet plumes over multiple successive flushes. Some other pathogens speculatively identified as being of potential concern for these reasons include gram-positive MRSA, Mycobacterium tuberculosis, and the pandemic H1N1/09 virus commonly known as "swine flu". There is no direct experimental evidence on disease transmission by toilet aerosols. Whether or not aerosols can contain norovirus, SARS coronavirus, or other pathogens has not been directly measured . The combination of cleaning and disinfecting surfaces is usually effective at removing contamination, although some pathogens such as norovirus have an apparent resistance to these techniques.
