I had no immunization records either. I am 48 and had to get vacinated for per NS requirement. When I had my first child they told me I had no immunity to measles per my blood work. Even though I remember getting it in high school. I had titers done before the start of NS that showed I had immunity to chicken pox and mumps, but not measles. ( I had chicken pox and mumps as a child.) My primary care doctor gave me two MMR shots. They are to be adminstered 4 weeks apart. They doctor had to check on this. I would check out the CDC website. I believe you will find your answer there. Also I just got hired a nurse tech at my local hospital and they are checking my titers again even with proof of immunization. They were adminstered appoximately 8 months ago and my titers were done about 9 months ago. This is a liitle off topic but my oldest child had chicken pox, mumps, and measles back to back in kindergarden even thoug he recieved his immunization. He also had roseola as an infant.