The author analyzes the aftermath of Edward Hooper’s suggestion that the trial of an oral polio vaccine (OPV) in the Belgian colonies of Africa engendered the pandemic form of the AIDS virus, HIV‐1. In response to Hooper’s book, The River (1999), the Royal Society in London held a conference to debate the origins of HIV. Examination of the quick dismissal of the OPV theory opens a space for legitimately challenging the widely held belief that the vaccine contamination question was convincingly resolved. This article interrogates the relationship between historiography and the making of scientific facts and history, suggesting that historians have been too credulous of scientists’ testimony. The further result of the lack of a thorough analysis of the evidence backing the OPV hypothesis has resulted in a missed opportunity to read The River as one of the few detailed accounts of the immense social, political, technological, and interspecies infrastructure constituted by Cold War vaccine production. This biomedical infrastructure dramatically changed the geographic and interspecies mobility of viruses in ways that may be impossible to reconstruct. Yet these potential transmission routes remain crucial to acknowledge. The COVID‐19 pandemic draws attention to the critical importance of studying The WetNet, a concept coined by the author to name the conceptual and material infrastructures of inter‐ and intraspecies fluid bonding.