The scripture says that the lust of the flesh is manifest. That means it is always here, and we are called upon to resist it and walk in the spirit rather than the flesh. It does not just go away because we become saved.
Galatians 5:19-21
19. Now the works of the flesh are manifest, which are these; Adultery, fornication, uncleanness, lasciviousness,
20. Idolatry, witchcraft, hatred, variance, emulations, wrath, strife, seditions, heresies,
21. Envyings, murders, drunkenness, revellings, and such like: of the which I tell you before, as I have also told you in time past, that they which do such things shall not inherit the kingdom of God.
The word manifest means as opposed to hidden. They are obvious in us all.
The desires to do these things are "obvious" and we are told not to practice them.
As the old preacher said, "A bird may fly over your head, but you do not have to let it land on your head."