PD Dr. med. Karl-Otto Fresen (1942 – 1980)
- Studied medicine at the University of Freiburg from 1962 to1968, written preliminary medical exam 1963, written secondary medical exam 1965, medical state exams 1968.
- Conferral of doctorate title in 1968 to become Doctor of Medicine after his work at the Institute of Pathology, University of Freiburg. (Prof. Dr. H. U. Zollinger) from 1965 until 1967.
- Medical assistant at the Hygiene Institute of the University of Freiburg (Prof. Dr. R. Haas) from July 1968 until 1969 and scientific assistant at the same institute from May 1969 until January 1970. Training in immunology and analysis of immunological and immune pathology matters (cooperated with PD. Dr. A. Vogt).
- Medical assistant from March 1970 until June 1970 at the Chirugischen Klinik (Surgical Clinic), Community Hospital Berlin-Neukölln (Prof. Dr. W. Irmer).
- Medical assistant from July 1970 until October 1970 at the Second Medical clinic, University of Munich (Prof. Dr. M. M. Forell).
- Scientific assistant from May 1971 until May 1972 at the Institute for Pathology in the cancer research department of the University of Zurich (PD. Dr. P. Sträuli). Scientific paper on tumour cell membranes.
- Research visit in June and July 1971 to Strangeways Research Laboratory, Cambridge, England (Prof. Dr. M. Abercrombie).
- Scientific assistant from May 1972 until January 1975 at the Institute for Medical Microbiology at the University of Zürich (Prof. Dr. E. Wiesmann). Training in medical microbiology. Scientific paper on changes to the surface membrane of tumour cells after infection with the oncolytic influenza virus (cooperated with Prof. Dr. J. Lindenmann).
- Scientific assistant from February 1975 until March 1977 at the Institute for Clinical Virology, University of Erlangen-Nuremberg (Prof. Dr. H. zur Hausen).
- Scientific assistant from April 1977 at the Institute for Virology, Centre for Hygiene, University of Freiburg (Prof. Dr. H. zur Hausen). Worked in clinical diagnostic virology and wrote a scientific paper on different strains of the Epstein Barr Virus.
- 1978 “Habilitation” thesis “A Biological and Immunological Study to Differentiate Between Strains of the Epstein Barr Virus”.