One can contract the plague through direct contact with the god, Mirad, or one of disciples, known as the Plague Priests, or if a non-infected comes into contact with the vomit of an infected. When contracting the plague through either plague critically fail a constitution saving throw presented by the priest ,and doing so one to contract the illness. The only other way to contract the plague is to get infected matter into your bloodstream, ie, a rat bite, a cut, or one must make a constitution save of 8 or higher, or become infected by the plague.