scholarly journals Host Genotype and Tissue Type Determine DWV Infection Intensity

2021 ◽  
Vol 1 ◽  
Author(s):  
Hannah J. Penn ◽  
Michael Simone-Finstrom ◽  
Sarah Lang ◽  
Judy Chen ◽  
Kristen Healy
Keyword(s):  
Honey Bee ◽  
Infection Intensity ◽  
The United States ◽  
Tissue Type ◽  
Body Parts ◽  
Virus Genotype ◽  
Host Genotype ◽  
Deformed Wing Virus ◽  
Genetic Stocks ◽  
Honey Bee Health

Varroa mite-vectored viruses such as Deformed wing virus (DWV) are of great concern for honey bee health as they can cause disease in individuals and increase colony mortality. Two genotypes of DWV (A and B) are prevalent in the United States and may have differential virulence and pathogenicity. Honey bee genetic stocks bred to resist Varroa mites also exhibit differential infection responses to the Varroa mite-vectored viruses. The goal of this project was to determine if interactions between host genotype could influence the overall infection levels and dissemination of DWV within honey bees. To do this, we injected DWV isolated from symptomatic adult bees into mite-free, newly emerged adult bees from five genetic stocks with varying levels of resistance to Varroa mites. We measured DWV-A and DWV-B dissemination among tissues chosen based on relevance to general health outcomes for 10 days. Injury from sham injections did not increase DWV-A levels but did increase DWV-B infections. DWV injection increased both DWV-A and DWV-B levels over time with significant host stock interactions. While we did not observe any differences in viral dissemination among host stocks, we found differences in virus genotype dissemination to different body parts. DWV-A exhibited the highest initial levels in heads and legs while the highest initial levels of DWV-B were found in heads and abdomens. These interactions underscore the need to evaluate viral genotype and tissue specificity in conjunction with host genotype, particularly when the host has been selected for traits relative to virus-vector and virus resistance.

scholarly journals Impact of Chronic Exposure to Sublethal Doses of Glyphosate on Honey Bee Immunity, Gut Microbiota and Infection by Pathogens

2021 ◽  
Vol 9 (4) ◽  
pp. 845
Author(s):  
Loreley Castelli ◽  
Sofía Balbuena ◽  
Belén Branchiccela ◽  
Pablo Zunino ◽  
Joanito Liberti ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Honey Bee ◽  
Chronic Exposure ◽  
Pollination Services ◽  
Deformed Wing Virus ◽  
Immune Genes ◽  
Bee Health ◽  
Honey Bee Health ◽  
Sublethal Doses ◽  
The Impact

Glyphosate is the most used pesticide around the world. Although different studies have evidenced its negative effect on honey bees, including detrimental impacts on behavior, cognitive, sensory and developmental abilities, its use continues to grow. Recent studies have shown that it also alters the composition of the honey bee gut microbiota. In this study we explored the impact of chronic exposure to sublethal doses of glyphosate on the honey bee gut microbiota and its effects on the immune response, infection by Nosema ceranae and Deformed wing virus (DWV) and honey bee survival. Glyphosate combined with N. ceranae infection altered the structure and composition of the honey bee gut microbiota, for example by decreasing the relative abundance of the core members Snodgrassella alvi and Lactobacillus apis. Glyphosate increased the expression of some immune genes, possibly representing a physiological response to mitigate its negative effects. However, this response was not sufficient to maintain honey bee health, as glyphosate promoted the replication of DWV and decreased the expression of vitellogenin, which were accompanied by a reduced life span. Infection by N. ceranae also alters honey bee immunity although no synergistic effect with glyphosate was observed. These results corroborate previous findings suggesting deleterious effects of widespread use of glyphosate on honey bee health, and they contribute to elucidate the physiological mechanisms underlying a global decline of pollination services.

scholarly journals Honey Bee Virus Transmission via Hive Products

2020 ◽  
Vol 7 (3) ◽  
pp. 96 ◽  
Author(s):  
Dominik Schittny ◽  
Orlando Yañez ◽  
Peter Neumann
Keyword(s):  
Honey Bee ◽  
Virus Transmission ◽  
Positive Association ◽  
Pathogen Transmission ◽  
Transmission Risk ◽  
Virus Genotype ◽  
Commercial Products ◽  
Deformed Wing Virus ◽  
A Genome ◽  
Significant Difference

The global trade of honey bee hive products has raised concern about pathogen transmission. However, the efficacy of hive products as virus vehicles is poorly understood. Here, we investigated the transmission capacity of hive products for Deformed wing virus genotype A (DWV-A) in a fully-crossed hoarding cage experiment and estimated the transmission risk by screening commercial products. Western honey bee workers were provided with honey, pollen and wax either contaminated with high (~2 × 109), medium (~1.7 × 108), low (~8 × 106) or zero (control) DWV-A genome copies. For 10 days, mortality was monitored. Then, virus titers were quantified in bee heads and 38 commercial products using RT-qPCR. For honey and pollen, a positive association between DWV-A concentration and mortality was observed. High concentrations always resulted in infections, medium ones in 47% of cases and low ones in 20% of cases. No significant difference was observed between the tested products. In commercial honey and pollen, 7.7 × 102–1.8 × 105 and 1.4 × 103–1.3 × 104 DWV-A copies per gram were found, respectively. The results show that DWV-A transmission via hive products is feasible. The risk of introducing novel viruses and/or strains should be considered in trade regulations by including virus analyses for health certificates of hive products

scholarly journals Deformed Wing Virus Infection in Honey Bees (Apis mellifera L.)

2019 ◽  
Vol 56 (4) ◽  
pp. 636-641 ◽  
Author(s):  
Roman V. Koziy ◽  
Sarah C. Wood ◽  
Ivanna V. Kozii ◽  
Claire Janse van Rensburg ◽  
Igor Moshynskyy ◽  
...  
Keyword(s):  
Apis Mellifera ◽  
Honey Bee ◽  
Honey Bees ◽  
Rna Virus ◽  
Mandibular Glands ◽  
Deformed Wing Virus ◽  
Clinically Normal ◽  
Bee Health ◽  
Honey Bee Health ◽  
Honey Bee Workers

Deformed wing virus (DWV) is a single-stranded RNA virus of honey bees ( Apis mellifera L.) transmitted by the parasitic mite Varroa destructor. Although DWV represents a major threat to honey bee health worldwide, the pathological basis of DWV infection is not well documented. The objective of this study was to investigate clinicopathological and histological aspects of natural DWV infection in honey bee workers. Emergence of worker honey bees was observed in 5 colonies that were clinically affected with DWV and the newly emerged bees were collected for histopathology. DWV-affected bees were 2 times slower to emerge and had 30% higher mortality compared to clinically normal bees. Hypopharyngeal glands in bees with DWV were hypoplastic, with fewer intracytoplasmic secretory vesicles; cells affected by apoptosis were observed more frequently. Mandibular glands were hypoplastic and were lined by cuboidal epithelium in severely affected bees compared to tall columnar epithelium in nonaffected bees. The DWV load was on average 1.7 × 106 times higher ( P < .001) in the severely affected workers compared to aged-matched sister honey bee workers that were not affected by deformed wing disease based on gross examination. Thus, DWV infection is associated with prolonged emergence, increased mortality during emergence, and hypoplasia of hypopharyngeal and mandibular glands in newly emerged worker honey bees in addition to previously reported deformed wing abnormalities.

scholarly journals Acaricide Treatment Affects Viral Dynamics in Varroa destructor-Infested Honey Bee Colonies via both Host Physiology and Mite Control

2011 ◽  
Vol 78 (1) ◽  
pp. 227-235 ◽  
Author(s):  
Barbara Locke ◽  
Eva Forsgren ◽  
Ingemar Fries ◽  
Joachim R. de Miranda
Keyword(s):  
Honey Bee ◽  
Varroa Destructor ◽  
Synergistic Effects ◽  
Physiological Effect ◽  
Mite Infestation ◽  
Initial Increase ◽  
Virus Infections ◽  
Deformed Wing Virus ◽  
Content Type ◽  
Honey Bee Health

ABSTRACTHoney bee (Apis mellifera) colonies are declining, and a number of stressors have been identified that affect, alone or in combination, the health of honey bees. The ectoparasitic miteVarroa destructor, honey bee viruses that are often closely associated with the mite, and pesticides used to control the mite population form a complex system of stressors that may affect honey bee health in different ways. During an acaricide treatment using Apistan (plastic strips coated with tau-fluvalinate), we analyzed the infection dynamics of deformed wing virus (DWV), sacbrood virus (SBV), and black queen cell virus (BQCV) in adult bees, mite-infested pupae, their associatedVarroamites, and uninfested pupae, comparing these to similar samples from untreated control colonies. Titers of DWV increased initially with the onset of the acaricide application and then slightly decreased progressively coinciding with the removal of theVarroamite infestation. This initial increase in DWV titers suggests a physiological effect of tau-fluvalinate on the host's susceptibility to viral infection. DWV titers in adult bees and uninfested pupae remained higher in treated colonies than in untreated colonies. The titers of SBV and BQCV did not show any direct relationship with mite infestation and showed a variety of possible effects of the acaricide treatment. The results indicate that other factors besidesVarroamite infestation may be important to the development and maintenance of damaging DWV titers in colonies. Possible biochemical explanations for the observed synergistic effects between tau-fluvalinate and virus infections are discussed.

scholarly journals Impacts of Diverse Natural Products on Honey Bee Viral Loads and Health

2021 ◽  
Vol 11 (22) ◽  
pp. 10732
Author(s):  
Dawn L. Boncristiani ◽  
James P. Tauber ◽  
Evan C. Palmer-Young ◽  
Lianfei Cao ◽  
William Collins ◽  
...  
Keyword(s):  
Natural Products ◽  
Immune Responses ◽  
Honey Bee ◽  
Honey Bees ◽  
Food Sources ◽  
Deformed Wing Virus ◽  
Bee Health ◽  
Honey Bee Health ◽  
Living Organisms ◽  
Bee Disease

Western honey bees (Apis mellifera), a cornerstone to crop pollination in the U.S., are faced with an onslaught of challenges from diseases caused by parasites, pathogens, and pests that affect this economically valuable pollinator. Natural products (NPs), produced by living organisms, including plants and microorganisms, can support health and combat disease in animals. NPs include both native extracts and individual compounds that can reduce disease impacts by supporting immunity or directly inhibiting pathogens, pests, and parasites. Herein, we describe the screening of NPs in laboratory cage studies for their effects on honey bee disease prevention and control. Depending on the expected activity of compounds, we measured varied responses, including viral levels, honey bee immune responses, and symbiotic bacteria loads. Of the NPs screened, several compounds demonstrated beneficial activities in honey bees by reducing levels of the critical honey bee virus deformed wing virus (DWV-A and-B), positively impacting the gut microbiome or stimulating honey bee immune responses. Investigations of the medicinal properties of NPs in honey bees will contribute to a better understanding of their potential to support honey bee immunity to fight off pests and pathogens and promote increased overall honey bee health. These investigations will also shed light on the ecological interactions between pollinators and specific floral food sources.

scholarly journals Occurrence and Molecular Phylogeny of Honey Bee Viruses in Vespids

Viruses ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 6 ◽  
Author(s):  
Sa Yang ◽  
Philippe Gayral ◽  
Hongxia Zhao ◽  
Yaojun Wu ◽  
Xuejian Jiang ◽  
...  
Keyword(s):  
Honey Bee ◽  
Phylogenetic Analyses ◽  
Virus Transmission ◽  
Deformed Wing Virus ◽  
Two Samples ◽  
Bee Health ◽  
Queen Cell ◽  
Honey Bee Health ◽  
Infection Processes ◽  
Bee Viruses

Since the discovery that honey bee viruses play a role in colony decline, researchers have made major breakthroughs in understanding viral pathology and infection processes in honey bees. Work on virus transmission patterns and virus vectors, such as the mite Varroa destructor, has prompted intense efforts to manage honey bee health. However, little is known about the occurrence of honey bee viruses in bee predators, such as vespids. In this study, we characterized the occurrence of 11 honey bee viruses in five vespid species and one wasp from four provinces in China and two vespid species from four locations in France. The results showed that all the species from China carried certain honey bee viruses, notably Apis mellifera filamentous virus (AmFV), Deformed wing virus (DWV), and Israeli acute paralysis virus (IAPV); furthermore, in some vespid colonies, more than three different viruses were identified. In France, DWV was the most common virus; Sacbrood virus (SBV) and Black queen cell virus (BQCV) were observed in one and two samples, respectively. Phylogenetic analyses of IAPV and BQCV sequences indicated that most of the IAPV sequences belonged to a single group, while the BQCV sequences belonged to several groups. Additionally, our study is the first to detect Lake Sinai virus (LSV) in a hornet from China. Our findings can guide further research into the origin and transmission of honey bee viruses in Vespidae, a taxon of ecological, and potentially epidemiological, relevance.

scholarly journals RNAseq Analysis Reveals Virus Diversity within Hawaiian Apiary Insect Communities

Viruses ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 397 ◽  
Author(s):  
Brettell ◽  
Schroeder ◽  
Martin
Keyword(s):  
Honey Bee ◽  
Large Scale ◽  
Pest Species ◽  
Insect Communities ◽  
Colony Losses ◽  
Viral Pathogen ◽  
Deformed Wing Virus ◽  
Virus Diversity ◽  
Bee Health ◽  
Honey Bee Health

Deformed wing virus (DWV) is the most abundant viral pathogen of honey bees and has been associated with large-scale colony losses. DWV and other bee-associated RNA viruses are generalists capable of infecting diverse hosts. Here, we used RNAseq analysis to test the hypothesis that due to the frequency of interactions, a range of apiary pest species would become infected with DWV and/or other honey bee-associated viruses. We confirmed that DWV-A was the most prevalent virus in the apiary, with genetically similar sequences circulating in the apiary pests, suggesting frequent inter-species transmission. In addition, different proportions of the three DWV master variants as indicated by BLAST analysis and genome coverage plots revealed interesting DWV-species groupings. We also observed that new genomic recombinants were formed by the DWV master variants, which are likely adapted to replicate in different host species. Species groupings also applied when considering other viruses, many of which were widespread in the apiaries. In social wasps, samples were grouped further by site, which potentially also influenced viral load. Thus, the apiary invertebrate community has the potential to act as reservoirs of honey bee-associated viruses, highlighting the importance of considering the wider community in the apiary when considering honey bee health.

scholarly journals The Gut Microbiota Can Provide Viral Tolerance in the Honey Bee

2021 ◽  
Vol 9 (4) ◽  
pp. 871
Author(s):  
Christopher Dosch ◽  
Anja Manigk ◽  
Tabea Streicher ◽  
Anja Tehel ◽  
Robert J. Paxton ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Honey Bee ◽  
Honey Bees ◽  
Negative Effects ◽  
Positive Role ◽  
Viral Pathogen ◽  
Deformed Wing Virus ◽  
Bee Health ◽  
Honey Bee Health

Adult honey bees host a remarkably consistent gut microbial community that is thought to benefit host health and provide protection against parasites and pathogens. Currently, however, we lack experimental evidence for the causal role of the gut microbiota in protecting the Western honey bees (Apis mellifera) against their viral pathogens. Here we set out to fill this knowledge gap by investigating how the gut microbiota modulates the virulence of a major honey bee viral pathogen, deformed wing virus (DWV). We found that, upon oral virus exposure, honey bee survival was significantly increased in bees with an experimentally established normal gut microbiota compared to control bees with a perturbed (dysbiotic) gut microbiota. Interestingly, viral titers were similar in bees with normal gut microbiota and dysbiotic bees, pointing to higher viral tolerance in bees with normal gut microbiota. Taken together, our results provide evidence for a positive role of the gut microbiota for honey bee fitness upon viral infection. We hypothesize that environmental stressors altering honey bee gut microbiota composition, e.g., antibiotics in beekeeping or pesticides in modern agriculture, could interact synergistically with pathogens, leading to negative effects on honey bee health and the epidemiology and impact of their viruses.

scholarly journals Haemolymph removal by the parasite Varroa destructor can trigger the proliferation of the Deformed Wing Virus in mite infested bees (Apis mellifera), contributing to enhanced pathogen virulence

2018 ◽  
Author(s):  
Desiderato Annoscia ◽  
Sam P. Brown ◽  
Gennaro Di Prisco ◽  
Emanuele De Paoli ◽  
Simone Del Fabbro ◽  
...  
Keyword(s):  
Honey Bee ◽  
Varroa Destructor ◽  
Viral Evolution ◽  
Colony Losses ◽  
Viral Pathogen ◽  
Deformed Wing Virus ◽  
Bee Colony ◽  
Bee Health ◽  
Honey Bee Health ◽  
Mite Feeding

AbstractThe association between the Deformed Wing Virus and the parasitic mite Varroa destructor has been identified as a major cause of worldwide honey bee colony losses. The mite acts as a vector of the viral pathogen and can trigger its replication in infected bees. However, the mechanistic details underlying this tripartite interaction are still poorly defined, and, in particular, the causes of viral proliferation in mite infested bees.Here we develop and test a novel hypothesis - grounded in ecological predator-prey theory - that mite feeding destabilizes viral immune control through the removal of both viral ‘prey’ and immune ‘predators’, triggering uncontrolled viral replication. Consistent with this hypothesis, we show that experimental removal of increasing volumes of haemolymph from individual bees results in increasing viral densities. In contrast, we find no support for alternative proposed mechanisms of viral expansion via mite immune-suppression or within-host viral evolution.Overall, these results provide a new model for the mechanisms driving pathogen-parasite interactions in bees, which ultimately underpin honey bee health decline and colony losses.

scholarly journals Nationwide Screening for Bee Viruses and Parasites in Belgian Honey Bees

Viruses ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 890
Author(s):  
Severine Matthijs ◽  
Valérie De Waele ◽  
Valerie Vandenberge ◽  
Bénédicte Verhoeven ◽  
Jacqueline Evers ◽  
...  
Keyword(s):  
Viral Load ◽  
Real Time ◽  
Honey Bee ◽  
Honey Bees ◽  
High Viral Load ◽  
Deformed Wing Virus ◽  
Bee Health ◽  
Honey Bee Health ◽  
Varroa Mites ◽  
Paralysis Virus

The health of honey bees is threatened by multiple factors, including viruses and parasites. We screened 557 honey bee (Apis mellifera) colonies from 155 beekeepers distributed all over Belgium to determine the prevalence of seven widespread viruses and two parasites (Varroa sp. and Nosema sp.). Deformed wing virus B (DWV-B), black queen cell virus (BQCV), and sacbrood virus (SBV) were highly prevalent and detected by real-time RT-PCR in more than 95% of the colonies. Acute bee paralysis virus (ABPV), chronic bee paralysis virus (CBPV) and deformed wing virus A (DWV-A) were prevalent to a lower extent (between 18 and 29%). Most viruses were only present at low or moderate viral loads. Nevertheless, about 50% of the colonies harbored at least one virus at high viral load (>107 genome copies/bee). Varroa mites and Nosema sp. were found in 81.5% and 59.7% of the honey bee colonies, respectively, and all Nosema were identified as Nosema ceranae by real time PCR. Interestingly, we found a significant correlation between the number of Varroa mites and DWV-B viral load. To determine the combined effect of these and other factors on honey bee health in Belgium, a follow up of colonies over multiple years is necessary.

Sign in / Sign up

Export Citation Format

Share Document