Philosophy of Biology, Medicine, and Public Health
Sober describes the evolution of virulence, defined as “the average effect the disease has on the host’s lifespan after the host is infected.” He notes some of the factors that affect whether a high-virulence or a low-virulence strain will evolve by natural selection.
The Boston Review published an interesting exchange on the uses of models and evidence when setting public policies. The exchange begins with an article by philosopher Jonathan Fuller. Fuller compares public health epidemiology (which tends to favour models, a diversity of data, and a pragmatic methodology) to clinical epidemiology (which tends to favour evidence and quality of data, and adopts a conservative, skeptical methodology). Fuller believes that good epidemiology will combine both of these approaches. Infectious disease epidemiologist Mark Lipsitch disagrees with Fuller’s characterization of the competing approaches to epidemiology. Lipstich argues that the pandemic reveals not different philosophies of science, but instead different philosophies of action. Clinical epidemiologist John Ioannidis then replies to both Fuller and Lipstich. Ioannidis holds that in an emergency the first question is not whether to act, but how to act. The main challenge of epidemiology is to translate what we know—and what we know about what we know—into action that will do the most good. Ioannidis argues that good data are required in order to set good policy. Ioannidis stresses the need to account for the harms of the policies we adopt and to be prepared to change course if the data suggests the harms outweigh the benefits. Finally, Fuller draws some lessons from the exchange about the nature of science, values, and the weighing of harms and benefits in policy decisions.