I'm 27, Female- I have received the first two sets of the HPV vaccine (Guardasil, at walk-in immunization clinic), and was due in for the third set last week. I am unable to go in for the the third set until next week. Will the delay in receiving the third dose affect the effectiveness of the vaccine?
A delay of a couple of weeks is not going to make a difference in the effectiveness of the vaccine. Now if you were several months off the schedule, that may make a difference, but even there it would not be too much.
Three doses (shots) are recommended over a six month period. The CDC recommends that the second dose be given one to two months after the first, and the third dose be given about six months after the first dose.
So, you should be okay getting your injection next week.
If you are concerned about it, discuss the situation with the provider who is giving you the injection. Good luck.