You can also get hepatitis A from well water. It’s more of a sanitation issue than an illegals issue.
You can only get Hep A from well water IF your septic tank was being filled with Hep A poop over the prior four months; if a flood caused someone elses Hep A poop to get into your well water; or if your well water otherwise shares its strata of fresh water with the Hep A poop from far away, but which flows to your well water within four months via currents.