The Influenza Problem: Paradigms, a Pandemic, and the Search for Pfeiffer’s Bacillus

This dissertation challenges existing histories of the 1918-19 influenza pandemic which vilify the work of contemporary scientists for believing that a bacteria, B.influenzae, was the cause of flu. We now know influenza to be caused by a virus, but in 1918 medical thought was dictated by the bacteriological paradigm, which asserted that a bacteria was always the cause of infectious disease. However, in 1918 the bacteria which was ‘known’ to be the cause of influenza was not reliably found in sick patients. Doctors continued to search for the bacteria, even as a number of other aetiological agents, including a filter-passing virus, were proposed as alternative causes of the disease. Historians, including Mark Honigsbaum, see this preoccupation with B.influenzae as evidence of the scientific community being a prisoner of the bacteriological paradigm. Using Thomas S. Kuhn’s framework of scientific development, this dissertation undertakes a study of two British medical journals, The Lancet and the British Medical Journal, in order to ascertain the characteristics of the scientific community in the pandemic and post-pandemic periods, including how far they can be said to adhere to or move away from the paradigm which underpinned their work. It will conclude that rather than representing a moment of paradigm imprisonment, contributions to the two journals alongside contemporary medical literature instead demonstrate a period of re-evaluation and questioning that fits Kuhn’s model of ‘revolutionary science’. This will impact how historians conceptualise scientific development, particularly within the fields of bacteriology and virology, during the pandemic period.