Doktor der Rechte
Zeltner graduated with an M.D. and an LL.M. (master's in law) from the University of Berne. He specialized in human pathology and forensic medicine before becoming the head of Medical Services at the Bern University Hospital. He held various faculty positions at the University of Bern and at the Harvard School of Public Health. He is Doctor of law (honoris causa) of the University of Neuchâtel, Switzerland.