The present study demonstrates the central role of the queen in the evolution of N. ceranae infection of honey bee colonies. Indeed, the removal of the queen and the subsequent replacement with a younger queen decreased the proportion of Nosema-infected forager and house bees, which maintained the overall infection at a level compatible with colony viability. The emergence of brood is the primary natural defence against Nosema, allowing replacement of infected bees with healthy young bees, and thus, colonies with vigorous young queens are less prone to suffer Nosema infection Hence, to maintain colony health and survival, and to increase strength and productivity, it is essential to ensure the presence of young productive queens in colonies by regular replacement on an annual or biannual basis. This operation may be also beneficial to prevent health problems in the brood and, as demonstrated here, to control infection by Nosema and its deleterious effects at the colony level. The effect of induced queen replacement on Nosema spp. infection in honey bee (Apis mellifera iberiensis) colonies Cristina BotÃas, et al in Environmental Microbiology (2011) For correspondence E-mail mhiges (at) jccm.es *********************************************** The BEE-L mailing list is powered by L-Soft's renowned LISTSERV(R) list management software. For more information, go to: http://www.lsoft.com/LISTSERV-powered.html Guidelines for posting to BEE-L can be found at: http://honeybeeworld.com/bee-l/guidelines.htm