Next-generation sequence data demonstrate several pathogenic bee viruses in Middle East and African honey bee subspecies (Apis mellifera syriaca, Apis mellifera intermissa) as well as their cohabiting pathogenic mites (Varroa destructor)

Abstract

RNA viruses are associated with honey bee (Apis mellifera) colony losses in many parts of the world. Their consequences may be exacerbated when the ectoparasite mite Varroa destructor is present in hives. While evidence of pathogenic, viral-induced disease is abundant in western honey bees (Apis mellifera mellifera) from many parts of the world, less information exists regarding the pathogen load of Apis mellifera syriaca and Apis mellifera intermissa, honey bees from the Middle East and North Africa (MENA) that play substantial roles in regional beekeeping. Here, we used next-generation sequencing to evaluate the viral populations of these subspecies and their associated mites. We found that both A. m. syriaca and A. m. intermissa, as well as the Varroa mites infecting their colonies, bear a suite of RNA viruses including major pathogenic viruses like Deformed wing virus, Acute bee paralysis virus, Black queen cell virus and Sacbrood virus, and less common viruses (e.g., bee Macula-like virus and Apis mellifera filamentous virus). The two native honey bee MENA subspecies have acquired different but overlapping suites of pathogens, which also differ, but overlap, with the suites detected in the mites. The presence of plant viruses suggests that they were acquired from foraging for pollen and nectar. Phylogenetic analysis of the above common pathogenic RNA viruses showed unexpected genetic relationships with other known strains, indicative of import to MENA from outside of the region. Our findings indicate that it is important to carefully consider the impact of the movement of queens and mobile colonies, and the effects such movement have, on the transmission of disease.

New Viruses from the Ectoparasite Mite Varroa destructor Infesting Apis mellifera and Apis cerana

“…The experimental colonies of A. m. ligustica (worker bees N = 48, from hives 1, 3, 5, and 23, (4 bees per hive), 14 (6 bees), 81 (9 bees), and 401 (1 bee); mites N = 606, from the same hives (85 of them from emerging bees and the rest from free falling mites), collected between October to February 2016, were described before [23]; A. m. syriaca (workers N = 15, from a subcollection of 500 workers from colonies from several apiaries; mites = 20, from tens of mites that were collected in 2013) and A. m. intermissa (workers N = 15, from a subcollection of 500 workers; V. destructor mites N = 27, from tens of mites that were collected in 2013) were described previously [24]. A. cerana drones ( N = 6) and V. destructor mites ( N = 20) were sampled during spring 2016 (December) in Phrae, Thailand from two colonies 3c and 4c untreated against mites (3 drones and 20 mites from each colony, respectively).…”

“…RNA extraction from all A. mellifera and mite samples was carried out using TRI Reagent ® (Sigma-Aldrich, Israel) according to the manufacturer’s instructions as published before [24,30]. RNA from A. cerana drones and the corresponding V. destructor mites was individually extracted using a GenJet RNA purification Kit (Thermo Scientific, Burlington, Canada) according to the manufacturer’s instructions.…”

“…The obtained contigs were translated and aligned to the GenBank nonredundant (NR) database by Blastx [32]. Next-generation sequencing (NGS) of the RNA from A. m. ligustica , A. m. intermissa , and A. m. syriaca honeybees and corresponding V. destructor mites was described previously [23,24]. Metagenomic analysis of A. m. ligustica , A. m. intermissa , and A. m. syriaca subspecies and A. cerana bees, and of V. destructor mites samples were carried out as described previously and in Section 2.8 [30].…”

“…To look for possible variations in virus composition we investigated the viral populations in samples of three A. mellifera subspecies from the Middle East and North Africa (MENA) regions and their parasitic V. destructor mites as well as from A. cerana and their V. destructor mites. For this purpose we used next-generation sequencing (NGS) and performed metagenomics analysis of viral populations from samples of A. m. ligustica colonies from Israel [23] and their V. destructor mites, from Western honeybee subspecies from the MENA region— A. m. intermissa and A. m. syriaca [24]—and their V. destructor mites, and A. cerana and their V. destructor mites from Thailand. In this study, the viral composition and loads from samples of each bee species and its mite were determined, viral loads and viruses of interest were validated and characterized using molecular biology tools.…”

Next-Generation Sequencing on Insectivorous Bat Guano: An Accurate Tool to Identify Arthropod Viruses of Potential Agricultural Concern

“…Although viruses belonging in the Dicistroviridae family have been described worldwide, only a few studies have been carried out in African mainland [12,23,29,30,[45][46][47]. In this study, we described the full-length sequences of two Cripavirus (BSRV-like and ALPV) and one Aparavirus (ABPV) obtained from the faeces of insectivorous bat species (Hipposideros caffer) collected in a cave dwelling in Zimbabwe.…”