Neonicotinoid Clothianidin reduces honey bee immune response and contributes to Varroa mite proliferation

• Published in: Nature communications 2020-11, Vol.11 (1), p.5887-7, Article 5887
• Main Authors: Annoscia, Desiderato, Di Prisco, Gennaro, Becchimanzi, Andrea, Caprio, Emilio, Frizzera, Davide, Linguadoca, Alberto, Nazzi, Francesco, Pennacchio, Francesco
• Format: Article
• Language: English
• Subjects: 38; 631/158; 631/326/417; 631/326/596; 631/601/1466; 64; Animals; Bees - drug effects; Bees - immunology; Bees - parasitology; Guanidines - toxicity; Host-Parasite Interactions; Humanities and Social Sciences; Insecticides - toxicity; multidisciplinary; Neonicotinoids - toxicity; Science; Science (multidisciplinary); Thiazoles - toxicity; Varroidae - growth & development; Varroidae - physiology
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-020-19715-8

The neonicotinoid Clothianidin has a negative impact on NF-κB signaling and on immune responses controlled by this transcription factor, which can boost the proliferation of honey bee parasites and pathogens. This effect has been well documented for the replication of deformed wing virus (DWV) induced by Clothianidin in honey bees bearing an asymptomatic infection. Here, we conduct infestation experiments of treated bees to show that the immune-suppression exerted by Clothianidin is associated with an enhanced fertility of the parasitic mite Varroa destructor , as a possible consequence of a higher feeding efficiency. A conceptual model is proposed to describe the synergistic interactions among different stress agents acting on honey bees. Pesticides could increase bees’ susceptibility to parasites, but the nature of this interaction has been unclear. Here the authors show that the pesticide Clothianidin reduces the wound healing immune response in bees, allowing the ectoparasitic Varroa mites to consume more bee hemolymph and amplify reproduction.