Prof Torresi has a longstanding commitment to the practice, teaching and research in infectious diseases. His practice encompasses the breadth of clinical infectious diseases in both hospital and community acquired infections and he has been involved in numerous clinical trials in viral hepatitis, vaccines and virology.
He has long been involved in the teaching of medical students and medical practitioners in several aspects of infectious diseases, travel and tropical medicine. He has research activities in basic virology, in particular hepatitis B and C pathogenesis, immunology and vaccine research. He also has ongoing clinical and research interests in travel medicine.