retrovaccination

from The Century Dictionary.

• noun Vaccination of a cow with human virus.
• noun In medicine, the act of vaccinating with lymph derived from a cow which has previously been inoculated with vaccine matter from the human subject; the act of passing vaccine matter through a cow.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Med.) The inoculation of a cow with human vaccine virus.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun medicine The inoculation of a cow with human vaccine virus.