Abstract / Summary
Extracellular vesicles (EVs), including exosomes/small EVs of approximately 30–150 nm, are increasingly investigated as biologically derived carriers for infectious-disease therapeutics and diagnostics. This review critically integrates two previously separated themes: how pathogens and infected host cells reshape EV cargo during host–pathogen interactions, and how these same biological principles can be exploited to design targeted EV-mediated drug-delivery systems. We focus on intracellular and barrier-protected infections, including HIV, hepatitis viruses, Epstein–Barr virus, Mycobacterium tuberculosis , SARS-CoV-2 and leishmaniasis, while distinguishing conceptual promise from in vitro evidence, animal studies and early clinical experience. We also summarize EV biogenesis only where it informs engineering, compare drug-loading and surface-modification strategies, and identify disease-specific barriers such as macrophage residence, granuloma penetration, blood–brain barrier trafficking, viral reservoirs and manufacturing heterogeneity. Current evidence supports EVs as promising precision carriers, but clinical translation remains constrained by terminology, isolation and characterization standards, potency assays, biodistribution, safety, scalable manufacturing and regulatory classification. Alignment with MISEV2023 reporting principles and pathogen-specific efficacy models will be essential before EV-based infectious-disease therapeutics can move from experimental platforms to reproducible clinical products.