On modes of disease transmission and the hidden shape of pandemics: A review of by Joshua Weitz.

The importance of asymptomatic transmission was a key discovery in our efforts to study and intervene in the COVID-19 pandemic. In (Johns Hopkins University Press, 2024), Joshua Weitz uses this aspect of SARS-CoV-2 natural history to discuss many counterintuitive characteristics of the pandemic. In this essay, I engage the arguments in the book, and discuss why asymptomatic transmission is such a critical dimension of the study of infectious diseases. I explore ideas contained within and connect them to related issues in evolutionary virology and disease ecology, including epistemic uncertainty and the evolution of virulence. Furthermore, I comment on the broader messages in the text, including the gap between scientific knowledge and social understanding.