In "Letters from the Other Side Part 1", the infected Meghan commits suicide by jumping into a river so the Big Death will die with her. However, a river could easily carry her body to a downstream community and cause them to become infected if they tried to drag her body out of the water. It is made clear that this doesn’t actually happen (as dead bodies stop being contagious after a few days and the virus hasn’t returned after several weeks or months in later episodes), but the risk that it could have happened is still scary.
