Herbal Immunotherapy in Infectious Diseases

Abstract

Herbal immunotherapy in infectious disease sits in an interesting methodological position: a long tradition of use in Ayurveda, TCM and the European herbal tradition, a respectable and growing mechanistic literature, and an applied clinical evidence base that grew substantially during and after the COVID-19 pandemic without yet reaching settled consensus on which applications are truly clinically validated. We consolidated 94 peer-reviewed studies published between 2012 and 2024 that evaluated herbal immunotherapy applications in infectious-disease contexts. Studies were grouped into five application frames: H1 (antiviral mechanisms), H2 (antibacterial approaches), H3 (immunomodulation in chronic infection), H4 (adjunctive therapy in severe infection / sepsis), and H5 (preventive and post-exposure immunoprophylaxis). Each frame was scored on the Herbal Immunotherapy Validation Index (HIVI), a weighted composite across mechanistic evidence, in vivo evidence, clinical evidence, safety in immune-compromised populations, and deployment feasibility. Antiviral mechanisms (H1) and preventive immunoprophylaxis (H5) scored highest, at HIVI 0.852 and 0.814. Adjunctive therapy in severe infection (H4) scored lowest, reflecting the genuine safety caution warranted in critically-ill populations. Our reading is that herbal immunotherapy has a defensible preventive and mild-infection role, with severe-infection use remaining the setting where conservative evidence standards are most important.