The Collaborative International Dictionary of English v.0.48:
Infest \In*fest"\, v. t. [imp. & p. p. Infested; p. pr. & vb.
n. Infesting.] [L. infestare, fr. infestus disturbed,
hostile, troublesome; in in, against + the root of defendere:
cf. F. infester. See Defend.]
To trouble greatly by numbers or by frequency of presence; to
disturb; to annoy; to frequent and molest or harass; as,
fleas infest dogs and cats; a sea infested with pirates.
To poison vermin that infest his plants. --Cowper.
These, said the genius, are envy, avarice,
superstition, love, with the like cares and passions
that infest human life. --Addison.
And the cares, that infest the day,
Shall fold their tents, like the Arabs,
And as silently steal away. --Longfellow.