Tuberculosis is one of the great scourges of mankind and until recently a major cause of death in Europe and America. In developing countries it still kills millions despite chemotherapy. Although Koch discovered the tubercle bacillus more than a century ago, the epidemiology of the disease is still poorly understood. Its greatest enigma is why tuberculous infections occasionally cause disease but mostly remain asymptomatic. Co-infection with HIV is the only known cause of progression from infection to disease, but most tuberculosis victims are HIV negative. In Courtesans and Consumption evidence is presented that there must be another virus that causes progression to disease; a virus that like HIV can be transmitted sexually and via blood contacts. Nico Nagelkerke (1951) is a widely published biostatistician and infectious disease epidemiologist. He has worked in the fields of HIV, tuberculosis, and other infectious diseases in several countries including Kenya and his native country the Netherlands. Currently, he is professor of biostatistics in the United Arab Emirates.