I was an MD at Karolinska Institutet since 1973, and in 1980 I became a specialist in infectious diseases. I became an associate professor in 1987 and a professor in 2001.

Previous assignments as Epidemiologist in WHO Smallpox Eradication Programme and Global Programme on AIDS, WHO, and memberships in a number Technical Expert Committees within Malaria, WHO.

Over 300 scientific publications, mostly within malaria.

Previously Chairman of the Board of Worldwide Malarial Resistance Network (WWARN), President of Médecins du Monde Sweden and Member of the Board of Roll Back Malaria Partnership. Presently Chairman of the Board of Infectious Disease Data Observatory (IDDO).