Pollinators comprise a wide range of animal species, including insects, birds, lizards and bats, all of which are critical to ecosystem health and food security. The vast majority of pollinator species are wild, including more than 20,000 species of bees, and therefore, they play a key role in the sustainability of ecosystems around the world. Because managed and wild bees share the same environment, food resources, and sometimes the same predators, a constant flow of pathogen transmission occurs between them. This leads to a host–pathogen population dynamic in which a single pathogen can parasitize new hosts and a single host can be parasitized by a number of new pathogens. These new parasitism events create a multihost system in which the population dynamics of each pathogen depend on itself, the coparasitism situation in the same host, and the circumstances of the host. These complex systems, involving transmission events, can contribute to reducing the size of pollinating entomofauna populations and their biodiversity, abundance, and distribution. This chapter examines the possibility that pathogens from managed bees can find a new host in wild bees and vice versa and examines the factors involved in the transmission of pathogens in bee communities.