EN
Nosema ceranae and Nosema apis are etiological agents of nosemosis, a disease of adult honey bees. They are intracellular microsporidian parasites infecting the midgut epithelial cells of honeybees. N. ceranae was previously believed to be restricted to the Asian honey bee, Apis cerana, but now this parasite is also found in the European honey bee (Apis mellifera) across most of the world. Some surveys suggest that N. ceranae is a serious threat to the global beekeeping industry because N. ceranae induces a significantly higher mortality in honey bees than N. apis does. Other experiments indicate only minor differences in the infectious dose and multiplication rate between the two species. Moreover, the mortality caused by N. ceranae in these experiments was not significantly higher than that induced by N. apis. This review presents the epidemiology of nosemosis, diagnostic tests for the identification of Nosema spp. and the possibilities of treating this disease.