The Antiviral Response in Insect Vectors: Immune Mechanisms and Implications for Disease Control

Insect vectors use a range of antiviral responses that influence their ability to acquire, replicate, and transmit human, animal, and plant viruses. Advances in comparative genomics, systems biology, transgenic tools, and single-cell profiling have identified both conserved immune frameworks and substantial divergence in antiviral strategies across vector and nonvector insects. This review examines the major antiviral pathways, including the RNA interference, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathways, as well as humoral and cellular responses, with a focus on recent findings that expand our understanding of virus-vector interactions. Evidence shows that viral recognition, downstream signaling, and the effects of individual pathways vary widely among vector species, tissues, virus families, and even individual viruses. By integrating cross-system comparisons, this review outlines emerging principles that govern antiviral responses in insect vectors and identifies key mechanistic gaps that limit current knowledge and the development of targeted transmission-blocking interventions.