Clinical experience with therapeutic vaccines designed for patients with hepatitis.

Franciscan missionary Giovanni Di Plano Carpini traveled in 1245 to a country named Yeke Tartar, to visit a certain man called Genghis Khan. His journey's report narrated peculiar dietary habits of the locals: "they eat anything, even lice". Little that Carpini knew, he had actually documented the earliest known to us record of oral vaccination against blood-borne infections - an approach that is still used occasionally in the present-day Mongolia for therapy of hepatitis.