Not sure if this is even a bug, but it definitely worths getting people's attention.
https://steamuserimages-a.akamaihd.net/ ... 9E57854AC/
The screenshot link above shows that there's a note filled with blood (obviously death note) at the bottom of the screen. But Plaguebearer started off harmless though? They can only infect people till they turn Pestilence. If the death note is for Pestilence it would make sense.