Prof Bjarnsholt is a global expert in the role of biofilms in chronic infections, with over 270 peer reviewed publications in the biofilm field. His research focuses on biofilm formation and the role of bacterial biofilm in chronic infections, both in vitro, animal models and ex vivo material from chronic infections. Bjarnsholt is interested as to how bacteria initiate biofilms in the human body and why the immune defense seems to fail both in the initial infection and later in the chronic infection.  His research also seeks to develop tools and methods to enable fast diagnosis of these infections, for better treatment and possible prevention. For this, Bjarnsholt works in close collaboration with clinicians at most of the major hospitals in Denmark.