vaccine
you need tetnaus shot (in short supply, costs $50 to get in NJ),
MMR and chicken pox.
If you have received the last two, then there are blood tests avaialable to prove that you have and would be sufficient. These are- MMR titer, costs $87 and varicella titler $68.
If you are out of USA get these three vaccines and get a certificate from the physician.
In addition, you need to get tested for TB and HIV, which is done by the INS nominated civil surgeon who shall be giving you the certificate, generally charge $215, including the above two tests.