The robust and pestilential grey squirrel thrived in the area while the red squirrel disappeared.这种体格强壮、具破坏性的灰松鼠在这一地区大量繁殖，而红松鼠则消失了。People were dependent for their water supply on this pestilential stream.人们靠这条可致瘟疫的溪流取水。A pestilential fever spread through the camp.一种致命的热病在营地传染开来。