Are you aware of the fact that there is discussion going on about the possible implementation of immunization compliance programs for adults? Could there come a time soon when government will treat you like a family pet and you will have to be up-to-date with your vaccines? In your case it would be a lot more serious because not being up-to-date could cause a denial of health care or perhaps employers will need to see that you've complied with such a program in order to get or keep your job.