How long can itching persist after a prolonged scabies infection?

2 weeks: Assuming you have been adequately treated, as the mites die, they can cause itching that is even more intense than the original scabies infection. If persistant, call your provider as this can also be a sign of incomplete treatment too. Occasionally, secondary bacterial infection called impetigo develops. If you are having a lot of crusting or oozing, impetigo may be making you itch--get seen.