It was the same unfortunate woman/RN.
Reading between the lines, she should have been following protocols.
Something went wrong.
Apparently, she was living at her home after the priest died, and who knows who has been exposed via her.
I am thinking that she was using those standard isolation outfits that they use for less deadly stuff. They are not like the “spacesuits” that we have seen, and appear to have far less potential for protections.