in ‧ fest /ɪnˈfest/ BrE AmE verb [transitive usually passive]
[ Date: 1500-1600 ; Language: French ; Origin: infester , from Latin , from infestus 'angry and unfriendly' ]
1 . if insects, rats etc infest a place, there are a lot of them and they usually cause damage
be infested with something
The kitchen was infested with cockroaches.
shark-infested/rat-infested etc
shark-infested waters
2 . if things or people you do not want infest a place, there are too many of them:
an area infested with holiday homes
—infestation /ˌɪnfeˈsteɪʃ ə n/ noun [uncountable and countable]