Transmissible Oncogenic Viruses: Scientific Evidence for Haematic, Salivary and Airborne Routes — A Critical Review of the Primary Literature

The prevailing consensus reduces the transmission of oncogenic viruses to sexual and haematic routes. This document reviews the peer-reviewed primary literature and documents evidence for broader routes: blood, saliva, respiratory secretions, droplets and surgical aerosol.One point is held firm throughout: it is the virus (the causal agent) that is transmitted, not the cancer. Cancer is the late and conditional outcome of infection — decade-long latency, persistence, cofactors — and is not a contagious event.Five of the seven IARC Group 1 oncogenic viruses (EBV, KSHV/HHV-8, HPV, MCPyV, HBV) present evidence of colonisation of saliva and/or the respiratory tract; two (HCV, HTLV-1) do not. Evidence is graded by strength: the haematic route is demonstrated (Hladik 2006, Mbulaiteye 2003); the salivary route is documented (Pauk 2000, Heiberg 2010); respiratory secretions are documented for MCPyV (Goh 2009, Bialasiewicz 2009, Kantola 2009); droplet and surgical aerosol transmission is supported (Sawchuk 1989, Gloster 1995, Palma 2021); long-range fine aerosol transmission is plausible but not demonstrated (Wang 2021, Tang 2022/2026). Negative results are explicitly declared (Petersen 1976 for HBV; Subbarayan 2020 for HPV from electrocautery fumes).The document addresses the central epistemological problem: the absence of air-sampling studies for EBV, HHV-8 and MCPyV constitutes a methodological gap, not a demonstration of absence of transmission. Twenty-five primary sources with PubMed-verified PMIDs are identified.