Molecular detection of bee pathogens in honey

Abstract

Honey bees are affected by a wide variety of parasites and pathogens, some of them were previously found in bee honey. Considering that spore-forming microorganisms are expected to remain latent in raw honey, presence of microsporidia, spore-forming bacteria, and viruses protected by peptide structures might represent a threat for bees. It is widely known that parasites and pathogens are one of the main factors implied in the worldwide decline of wild pollinators and colony losses of managed bees, and their detection in honey could be used to prevent the spread of diseases among colonies. Honey from 57 apiaries of Argentina located in Buenos Aires, Córdoba, Corrientes, Entre Ríos, Formosa, La Rioja, Neuquén, Río Negro and Santa Fe provinces was collected between March and October, 2012. DNA was extracted from the pellet obtained by centrifugation of 10 g of honey and pathogen DNA was amplified by qPCR, and products were purified, sequenced and analysed using BLAST software. Honey from every apiary contained DNA of at least one pathogen, with a high occurrence of Apis mellifera filamentous virus (AmFV) and Apicystis bombi, although Nosema ceranae, Paenibacillus larvae, and Ascosphaera apis were also detected. Here, we report the presence of DNA of several bee pathogens in honey from commercial apiaries, and provide a fast and efficient screening method that could be useful to indirectly estimate pathogen presence in apiaries.