Evidence for virus-associated recapping behaviour in honey bees (Apis mellifera) with differential detection sensitivity between varroa-resistant and non-resistant colonies.

Social immunity is vital for protecting honey bee colonies from pathogens and parasites. Among these threats, the parasitic mite Varroa destructor is particularly devastating, both by weakening parasitized bees and by transmitting several potentially lethal viruses, most notably Deformed Wing Virus (DWV). To counteract varroa and the damage caused by viral epidemics, honey bees exhibit complex, socially organized hygienic behaviours, including Varroa Sensitive Hygiene (VSH), in which workers detect and remove varroa infested brood. A related behaviour, known as recapping, involves workers opening, inspecting, and re-sealing brood cells. While the triggers for VSH are increasingly understood, the factors driving recapping remain largely unexplored, especially the potential role of brood viral infections. This study investigates the relationship between brood viral infections and recapping, and whether this relationship differs between naturally varroa-resistant and non-resistant colonies. Building on earlier work linking varroa-parasitized brood to recapping, our results provide evidence that viruses may also play a role in this behaviour. These findings suggest that worker bees may be able to detect changes induced by different virus infections and modulate recapping accordingly, highlighting a nuanced interplay between pathogen pressure and social immunity.