Study 17 — Global Parasite-Attributable Cancer Burden and the Preventable Fraction: An Updated Integrated Estimate Using Population-Attributable Fraction Analysis Across Five Parasite–Cancer Pairs

Background. Chronic parasitic infections are Group 1 (IARC) carcinogens for at least three distinct cancers, yet no single published source has provided an updated, integrated estimate of current parasite-attributable cancer burden with an explicit preventable fraction analysis benchmarked to WHO control targets. This gap leaves parasite control programmes uncredited in global cancer prevention accounting. Methods. Population-attributable fraction (PAF) analysis using the Levin formula was applied to five parasite–cancer pairs: Schistosoma haematobium → bladder squamous cell carcinoma (SCC); Opisthorchis viverrini + Clonorchis sinensis → cholangiocarcinoma (CCA); Schistosoma japonicum → colorectal cancer…