How natural infection by Nosema ceranae causes honeybee colony collapse

• Published in: Environmental microbiology Vol. 10; no. 10; pp. 2659 - 2669
• Main Authors: Higes, Mariano, Martín-Hernández, Raquel, Botías, Cristina, Bailón, Encarna Garrido, González-Porto, Amelia V, Barrios, Laura, del Nozal, M. Jesús, Bernal, José L, Jiménez, Juan J, Palencia, Pilar García, Meana, Aránzazu
• Format: Journal Article
• Language: English
• Published: Oxford, UK Oxford, UK : Blackwell Publishing Ltd 01.10.2008; Blackwell Publishing Ltd
• Subjects: Animals; antibiotics; Antifungal Agents; Antifungal Agents - pharmacology; Apis cerana; Apis mellifera; Bees; Bees - microbiology; Bees - ultrastructure; brood rearing; Cyclohexanes; Cyclohexanes - pharmacology; death; disease control; etiology; Fatty Acids, Unsaturated; Fatty Acids, Unsaturated - pharmacology; Gastrointestinal Tract; Gastrointestinal Tract - pathology; honey; honey bee colonies; honey bees; isolation & purification; microbiology; Microscopy; Microscopy, Electron, Transmission; Microsporidiosis; Microsporidiosis - microbiology; Microsporidiosis - pathology; Microsporidium; Nosema; Nosema - isolation & purification; Nosema ceranae; pathology; pharmacology; pollen; Sesquiterpenes; Sesquiterpenes - pharmacology; spring; ultrastructure; winter
• ISSN: 1462-2912; 1462-2920; 1462-2920
• DOI: 10.1111/j.1462-2920.2008.01687.x

In recent years, honeybees (Apis mellifera) have been strangely disappearing from their hives, and strong colonies have suddenly become weak and died. The precise aetiology underlying the disappearance of the bees remains a mystery. However, during the same period, Nosema ceranae, a microsporidium of the Asian bee Apis cerana, seems to have colonized A. mellifera, and it's now frequently detected all over the world in both healthy and weak honeybee colonies. For first time, we show that natural N. ceranae infection can cause the sudden collapse of bee colonies, establishing a direct correlation between N. ceranae infection and the death of honeybee colonies under field conditions. Signs of colony weakness were not evident until the queen could no longer replace the loss of the infected bees. The long asymptomatic incubation period can explain the absence of evident symptoms prior to colony collapse. Furthermore, our results demonstrate that healthy colonies near to an infected one can also become infected, and that N. ceranae infection can be controlled with a specific antibiotic, fumagillin. Moreover, the administration of 120 mg of fumagillin has proven to eliminate the infection, but it cannot avoid reinfection after 6 months. We provide Koch's postulates between N. ceranae infection and a syndrome with a long incubation period involving continuous death of adult bees, non-stop brood rearing by the bees and colony loss in winter or early spring despite the presence of sufficient remaining pollen and honey.