CDC have a nice document called "When is clean too clean?" https://wwwnc.cdc.gov/eid/article/7/2/70-0225_article https://wwwnc.cdc.gov/eid/article/7/2/70-0225_a

CDC have a nice document called "When is clean too clean?" https://wwwnc.cdc.gov/eid/article/7/2/70-0225_article https://wwwnc.cdc.gov/eid/article/7/2/70-0225_article It explains the problems caused by skin irritation. You only need warm water to wash your hands. (But you need very hot water in the pipes, especially with long plumbing runs, to kill things like legionella).