Editing Pathogen transmission (section)

===Fecal–oral===
[[File:WPA Outhouse.jpg|thumb|1940 US WPA poster encouraging modernized privies]]
{{Main|Fecal–oral route}}
In the fecal-oral route, [[pathogens]] in [[Human feces|fecal]] particles pass from one person to the mouth of another person.  Although it is usually discussed as a route of transmission, it is actually a specification of the entry and exit portals of the pathogen, and can operate across several of the other routes of transmission.<ref name=":1" />  Fecal–oral transmission is primarily considered as an indirect contact route through contaminated food or water.  However, it can also operate through direct contact with feces or contaminated body parts, such as through [[anal sex]].<ref name=":2" /><ref name=":3" />  It can also operate through droplet or airborne transmission through the [[toilet plume]] from contaminated toilets.<ref name="Mead2013">{{cite journal | vauthors = Johnson DL, Mead KR, Lynch RA, Hirst DV | title = Lifting the lid on toilet plume aerosol: a literature review with suggestions for future research | journal = American Journal of Infection Control | volume = 41 | issue = 3 | pages = 254–258 | date = March 2013 | pmid = 23040490 | pmc = 4692156 | doi = 10.1016/j.ajic.2012.04.330 }}</ref><ref name="Jon2015">{{cite journal | vauthors = Jones RM, Brosseau LM | title = Aerosol transmission of infectious disease | journal = Journal of Occupational and Environmental Medicine | volume = 57 | issue = 5 | pages = 501–508 | date = May 2015 | pmid = 25816216 | doi = 10.1097/JOM.0000000000000448 | s2cid = 11166016 }}</ref>

Main causes of fecal–oral disease transmission include lack of adequate [[sanitation]] and poor [[hygiene]] practices - which can take various forms. Fecal oral transmission can be via foodstuffs or water that has become contaminated. This can happen when people do not adequately [[Hand washing|wash their hands]] after using the [[toilet]] and before preparing food or tending to patients.{{cn|date=June 2021}}

The fecal-oral route of transmission can be a public health risk for people in [[developing countries]] who live in urban [[slum]]s without access to adequate sanitation. Here, [[Human excreta|excreta]] or untreated [[sewage]] can pollute drinking water sources ([[Groundwater pollution|groundwater]] or surface water). The people who drink the [[Water pollution|polluted water]] can become infected. Another problem in some developing countries, is [[open defecation]] which leads to disease transmission via the fecal-oral route.{{cn|date=June 2021}}

Even in developed countries there are periodic system failures resulting in a [[sanitary sewer overflow]].  This is the typical mode of transmission for infectious agents such as [[cholera]], [[hepatitis A]], [[polio]], [[Rotavirus]], ''[[Salmonella]]'', and [[parasite]]s (e.g. ''[[Ascaris lumbricoides]]'').{{cn|date=June 2021}}