In 1998, he became board-licensed as a specialist in clinical biology. Since 1999, he is a professor at the University of Leuven in Belgium. Currently, he is associate chief of the department of laboratory medicine, and heads the clinical virology laboratory at the University Hospitals Leuven, Belgium. He is also the director of the AIDS reference laboratory and of several national reference laboratories. Professor Van Ranst was appointed in 1999 to the Belgian high council for public health, where he heads the vaccination department. Since 2007, he is responsible for influenza pandemic preparedness planning in Belgium, and he was responsible as interministerial commissary for the Belgian crisis management during the Mexican flu pandemic in 2009- 2010. Since 2012, he is the Chairman of the Department of Microbiology and Immunology at the University of Leuven. In his research laboratory, six PhD students and four master degree students are currently working on studies on the epidemiology and molecular evolution of DNA and RNA viruses. He published over 270 scientific papers in peer-reviewed and Medline-indexed journals and contributed chapters to six books on viral molecular evolution and bioinformatics. Professor Van Ranst teaches virology, epidemiology, and bioinformatics at the Faculty of Medicine at the University of Leuven and at the Hogeschool Leuven in Belgium. Since 1995, he holds an affiliate academic position at the Faculty of Natural Sciences at Charles University in Prague, Czech Republic, where he teaches Bioinformatics. In 2004 Professor Van Ranst was granted the European Clinical Virology Heine-Medin award of the European Society for Clinical Virology. In 2005, he received a doctor honoris causa degree at the University of Kalmar in Sweden.