Cancer in Slaughterhouse Workers, Surgeons and Nurses. An unexamined hypothesis is not a rejected one: transmission of oncogenic pathogens in the workplace.

Three occupational groups show an excess of cancer relative to their comparison groups: slaughterhouse workers, surgeons and nurses. For slaughterhouse workers the zoonotic oncogenic virus hypothesis is stated by the authors, published and publicly funded for over thirty years. For surgeons and nurses the same hypothesis is never formulated: stress, radiation or antineoplastic exposure are invoked instead. This document applies a single standard to all three. In nurses (Ratner 2010) the chemical explanation is contradicted by the observed pattern: leukaemia, the secondary malignancy expected first from antineoplastic exposure, is not significant, while the rectum — not among the documented sites — shows the clearest excess. In surgeons (Patel 2025) the comparison group already includes anaesthetists, intensivists and emergency physicians, so stress does not account for the MRR of 2.21. Contrary evidence (Yamanaka 2022, Subbarayan 2020), study limitations and alternative hypotheses are reported in full. The infectious hypothesis is not claimed to be demonstrated: what is observed is that it has never been sought where the data would make it relevant, and air sampling is proposed as the decisive experiment.