Chickenpox after Vaccine....?

Recently, spots had been appearing all over my body, so we went to the pedia. They told me it was breakthrough varicella(chickenpox) even though I had a vaccine some years ago. The spots dont itch that much, and it's almost a week since they appeared. I've also been taking acyclovir, for lessening the spots for at least 3 days(every 6 hrs). Can anyone tell me how long this will last?