Prof. Andersens research has been focused on the identification and characterisation of antigens, immune mechanisms and vaccine delivery systems that mediate protection against various pathogens and his main scientific interest has been immunity to intracellular pathogens such as Mycobacterium tuberculosis and Clamydia trachomatis. Prof. Andersen has pioneered work both on novel diagnostic assays (the IGRA assays), novel TB vaccines (H1/H4/H56) and the CAF series of liposomal adjuvants.