To inhabit a place in unpleasantly large numbers; to plague, harass.
To invade a host plant or animal.
To infest or overrun.
To attack; to infringe; to encroach on; to violate.
To move into.
To enter by force in order to conquer.
To make an unwelcome or uninvited visit or appearance, usually with an intent to cause trouble or some other unpleasant situation.