Immunological Determinants of Oncogenic Virus-Driven Cancers in Africa: Mechanisms, Co-Infections and Public Health Challenges

Oncogenic viruses contribute to approximately 20% of human cancers globally, with their impact falling disproportionately on populations in Sub-Saharan Africa. In this region, cervical cancer, hepatocellular carcinoma, endemic Burkitt lymphoma, and Kaposi sarcoma represent major causes of cancer-related morbidity and mortality, driven by persistent infection with human papillomavirus (HPV), hepatitis B and C viruses (HBV/HCV), Epstein–Barr virus (EBV), Kaposi sarcoma-associated herpesvirus (KSHV), and human T-lymphotropic virus-1 (HTLV-1). This review synthesizes current insights into the immunological mechanisms that underpin viral carcinogenesis in Africa, emphasizing how defective viral clearance, chronic immune activation, and immune evasion arise from the convergence of region-specific co-infections, host genetic diversity, and environmental exposures. We examine the mechanistic roles of HIV-associated CD4+ T cell depletion, malaria-induced perturbation of antiviral T cell immunity, helminth-driven T helper 2 polarization, and tuberculosis-associated inflammatory signaling in promoting viral persistence and malignant transformation. In addition, the influence of the extensive diversity of African human leukocyte antigens (HLA) and cytokine gene polymorphisms on antiviral immune responses and cancer susceptibility was discussed. We also assessed how virus-associated tumors establish profoundly immunosuppressive microenvironments characterized by impaired antigen presentation and the dominance