scholarly journals Vertical-transmission routes for deformed wing virus of honeybees (Apis mellifera)

2007 ◽  
Vol 88 (8) ◽  
pp. 2329-2336 ◽  
Author(s):  
Constanze Yue ◽  
Marion Schröder ◽  
Sebastian Gisder ◽  
Elke Genersch
Keyword(s):  
Apis Mellifera ◽  
Vertical Transmission ◽  
Clinical Symptoms ◽  
Viral Pathogen ◽  
Deformed Wing Virus ◽  
Colony Collapse ◽  
Virgin Queens ◽  
Viral Sequences

Deformed wing virus (DWV) is a viral pathogen of the European honeybee (Apis mellifera), associated with clinical symptoms and colony collapse when transmitted by the ectoparasitic mite Varroa destructor. In the absence of V. destructor, DWV infection does not result in visible symptoms, suggesting that mite-independent transmission results in covert infections. True covert infections are a known infection strategy for insect viruses, resulting in long-term persistence of the virus in the population. They are characterized by the absence of disease symptoms in the presence of the virus and by vertical transmission of the virus. To demonstrate vertical transmission and, hence, true covert infections for DWV, a detailed study was performed on the vertical-transmission routes of DWV. In total, 192 unfertilized eggs originating from eight virgin queens, and the same number of fertilized eggs from the same queens after artificial insemination with DWV-negative (three queens) or DWV-positive (five queens) semen, were analysed individually. The F0 queens and drones and F1 drones and workers were also analysed for viral RNA. By in situ hybridization, viral sequences were detected in the ovary of an F0 queen that had laid DWV-positive unfertilized eggs and was inseminated with DWV-positive semen. In conclusion, vertical transmission of DWV from queens and drones to drone and worker offspring through unfertilized and fertilized eggs, respectively, was demonstrated. Viral sequences in fertilized eggs can originate from the queen, as well as from drones via DWV-positive semen.

scholarly journals RT-PCR analysis of Deformed wing virus in honeybees (Apis mellifera) and mites (Varroa destructor)

2005 ◽  
Vol 86 (12) ◽  
pp. 3419-3424 ◽  
Author(s):  
Constanze Yue ◽  
Elke Genersch
Keyword(s):  
Varroa Destructor ◽  
Pcr Analysis ◽  
Body Parts ◽  
Rt Pcr ◽  
Larval Food ◽  
Viral Pathogen ◽  
Deformed Wing Virus ◽  
Significant Difference ◽  
Almost All ◽  
Viral Sequences

Deformed wing virus (DWV) is a honeybee viral pathogen either persisting as an inapparent infection or resulting in wing deformity. The occurrence of deformity is associated with the transmission of DWV through Varroa destructor during pupal stages. Such infections with DWV add to the pathology of V. destructor and play a major role in colony collapse in the course of varroosis. Using a recently developed RT-PCR protocol for the detection of DWV, individual bees and mites originating from hives differing in Varroa infestation levels and the occurrence of crippled bees were analysed. It was found that 100 % of both crippled and asymptomatic bees were positive for DWV. However, a significant difference in the spatial distribution of DWV between asymptomatic and crippled bees could be demonstrated: when analysing head, thorax and abdomen of crippled bees, all body parts were always strongly positive for viral sequences. In contrast, for asymptomatic bees viral sequences could be detected in RNA extracted from the thorax and/or abdomen but never in RNA extracted from the head. DWV replication was demonstrated in almost all DWV-positive body parts of infected bees. Analysing individual mites for the presence of DWV revealed that the percentage of DWV-positive mites differed between mite populations. In addition, it was demonstrated that DWV was able to replicate in some but not all mites. Interestingly, virus replication in mites was correlated with wing deformity. DWV was also detected in the larval food, implicating that in addition to transmission by V. destructor DWV is also transmitted by feeding.

Detection of viral sequences in semen of honeybees (Apis mellifera): Evidence for vertical transmission of viruses through drones

2006 ◽  
Vol 92 (2) ◽  
pp. 105-108 ◽  
Author(s):  
Constanze Yue ◽  
Marion Schröder ◽  
Kaspar Bienefeld ◽  
Elke Genersch
Keyword(s):  
Apis Mellifera ◽  
Vertical Transmission ◽  
Viral Sequences

scholarly journals Feral and managed honey bees, Apis mellifera (Hymenoptera: Apidae), in southern California have similar levels of viral pathogens

2021 ◽  
Author(s):  
Amy C Geffre ◽  
Dillon Travis ◽  
Joshua Kohn ◽  
James Nieh
Keyword(s):  
Apis Mellifera ◽  
Honey Bees ◽  
Southern California ◽  
Multiple Stressors ◽  
Pollination Services ◽  
Viral Pathogens ◽  
Viral Pathogen ◽  
Deformed Wing Virus ◽  
Native Bee ◽  
Queen Cell

Bees provide critical pollination services but are threatened by multiple stressors, including viral pathogens. Most studies of pollinator health focus on managed honey bees (Apis mellifera Linnaeus) (MHB) or native bee species, but a third player, the feral honey bee (FHB), requires further study. Spillover and spillback of viral pathogens between these managed, feral, and native bees is generating increasing interest. In this case study, we provide evidence suggesting that FHB colonies play an important role in viral pathogen dynamics of southern California pollinator communities because they act as reservoirs, of viral pathogens such as acute bee paralysis virus (ABPV), black queen cell virus (BQCV), and deformed wing virus (DWV). Surprisingly, even though FHB are not treated for diseases or parasites, they harbor similar pathogen loads to MHB, which are usually highly treated, suggesting the need for future studies to determine if FHB resist or are more resilient to viruses.

scholarly journals Short- and long-term effects of neonicotinoid application in rice fields, on the mortality and colony collapse of honeybees (Apis mellifera)

2013 ◽  
Vol 57 (2) ◽  
pp. 21-35 ◽  
Author(s):  
Takashi Matsumoto
Keyword(s):  
Apis Mellifera ◽  
Rice Field ◽  
Field Experiments ◽  
Late Summer ◽  
Colony Growth ◽  
Rice Fields ◽  
Long Term Effects ◽  
Brood Production ◽  
Colony Collapse

Abstract Declines in honeybee (Apis mellifera ) colonies have elicited great concern worldwide. Recently, many Japanese beekeepers have implied that midsummer use of a new insecticide, neonicotinoid, in rice fields, is causing widespread mortality of neighboring honeybees and frequently resulting in colony collapse. Since few field experiments have directly tested the effects of neonicotinoids, I addressed four research questions in the field. The questions are: 1) Does clothianidin application in rice fields cause the collapse of neighboring honeybee colonies? 2) Is colony collapse related to hive distance from the rice field? 3) Is the number of dead honeybee workers after spraying, related to hive distance from the field? 4) What are the long-term effects of neonicotinoid use on honeybee colony growth, especially brood production? In the late summer of 2010, honeybee hives were placed adjacent to two separate rice fields for 1 week. The hives were placed at the distance of 0, 30, 60, and 90 m. After spraying clothianidin, a daily count of dead worker honeybees was done for a week. Hives were weighed, and capped-brood areas were estimated weekly, for 2 months following insecticide application. Although the average number of dead workers ranged from 40 to over 100 within 24 hours after spraying, only a few dead workers were observed in the subsequent days. Distance from the rice field had no significant effect on the number of dead workers. There were no collapsed colonies during the 2-month, post-spray observation period. Hive weight and capped-brood area did not significantly differ among those hives placed at varying distances from the rice field. These results indicated that clothianidin spraying of the rice field increased the mortality of the honeybees, but did not always cause colony collapse.

scholarly journals Transcriptomic Responses of the Honey Bee Brain to Infection with Deformed Wing Virus

Viruses ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 287
Author(s):  
Marie C. Pizzorno ◽  
Kenneth Field ◽  
Amanda L. Kobokovich ◽  
Phillip L. Martin ◽  
Riju A. Gupta ◽  
...  
Keyword(s):  
Apis Mellifera ◽  
Honey Bees ◽  
Behavioral Changes ◽  
Rna Seq ◽  
Transcriptomic Response ◽  
Viral Pathogen ◽  
Deformed Wing Virus ◽  
And Function ◽  
G Protein Coupled ◽  
The Brain

Managed colonies of European honey bees (Apis mellifera) are under threat from Varroa destructor mite infestation and infection with viruses vectored by mites. In particular, deformed wing virus (DWV) is a common viral pathogen infecting honey bees worldwide that has been shown to induce behavioral changes including precocious foraging and reduced associative learning. We investigated how DWV infection of bees affects the transcriptomic response of the brain. The transcriptomes of individual brains were analyzed using RNA-Seq after experimental infection of newly emerged adult bees with DWV. Two analytical methods were used to identify differentially expressed genes from the ~15,000 genes in the Apis mellifera genome. The 269 genes that had increased expression in DWV infected brains included genes involved in innate immunity such as antimicrobial peptides (AMPs), Ago2, and Dicer. Single bee brain NMR metabolomics methodology was developed for this work and indicates that proline is strongly elevated in DWV infected brains, consistent with the increased presence of the AMPs abaecin and apidaecin. The 1361 genes with reduced expression levels includes genes involved in cellular communication including G-protein coupled, tyrosine kinase, and ion-channel regulated signaling pathways. The number and function of the downregulated genes suggest that DWV has a major impact on neuron signaling that could explain DWV related behavioral changes.

scholarly journals Field infection of a gilt and its litter demonstrates vertical transmission and effect on reproductive failure caused by porcine circovirus type 3 (PCV3)

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Diana S. Vargas-Bermúdez ◽  
Mayra A. Vargas-Pinto ◽  
José Darío Mogollón ◽  
Jairo Jaime
Keyword(s):  
Viral Load ◽  
Vertical Transmission ◽  
Clinical Symptoms ◽  
Porcine Circovirus Type ◽  
Porcine Circovirus ◽  
Single Infection ◽  
Viral Loads ◽  
Field Level ◽  
Type 3

Abstract Background PCV3 is a member of the Circovirus family, associated with disease and mortality in pigs. It is not clear whether PCV3 putatively causes clinical symptoms and disease. In the present case, we reported a gilt infected with PCV3 associated with reproductive failures, vertical transmission, tissue lesions, viral replication by in situ hybridization, and the hypothesis that some strains of PCV3 clade one are associated with reproductive failures at the field level. Case presentation In May 2019, a pig farm in Colombia reported increased reproductive failures, and the presence of PCV3 in gilts and sows was established in a single form or coinfections, mainly with PCV2 and PPV7. Ten sows with a single infection with PCV3 were found, and one gilt with a pre-farrowing serum viral load above 103 was studied. This gilt was followed up during the pre-farrowing, farrowing period and on her litter for 6 weeks. During dystocic farrowing, a mummy and ten piglets were released, including two weak-born piglets. The highest viral loads for PCV3 were found in the mummy and the placenta. In the weak-born piglets, there were viral loads both in serum and in tissues, mainly in the mesenteric ganglia and lung. Replication of PCV3 in these tissues was demonstrated by in situ hybridizations. PCV3 was also found in the precolostrum sera of piglets and colostrum, showing vertical transmission. The viral load in piglets decreased gradually until week six of life. The viral genome’s complete sequencing was made from the mummy, and its analysis classified it as PCV3 clade one. Conclusions This report confirms that PCV3 can cause disease at the field level, and putatively, in this case, we find the generation of reproductive failures. The ability of PCV3 to cause disease as a putative pathogen may be associated with the viral load present in the pig and the strain that is affecting the farm. For this case, we found that viral loads above 103 (4.93 log genomic copies / mL) in the gilt were associated with clinical manifestation and that some PCV3 strains belonging to clade one are more associated with the reproductive presentation.

scholarly journals Global soil moisture data derived through machine learning trained with in-situ measurements

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Sungmin O. ◽  
Rene Orth
Keyword(s):  
Machine Learning ◽  
Soil Moisture ◽  
Large Scale ◽  
Short Term Memory ◽  
Temporal Dynamics ◽  
Soil Moisture Data ◽  
Wide Range ◽  
Global Soil

AbstractWhile soil moisture information is essential for a wide range of hydrologic and climate applications, spatially-continuous soil moisture data is only available from satellite observations or model simulations. Here we present a global, long-term dataset of soil moisture derived through machine learning trained with in-situ measurements, SoMo.ml. We train a Long Short-Term Memory (LSTM) model to extrapolate daily soil moisture dynamics in space and in time, based on in-situ data collected from more than 1,000 stations across the globe. SoMo.ml provides multi-layer soil moisture data (0–10 cm, 10–30 cm, and 30–50 cm) at 0.25° spatial and daily temporal resolution over the period 2000–2019. The performance of the resulting dataset is evaluated through cross validation and inter-comparison with existing soil moisture datasets. SoMo.ml performs especially well in terms of temporal dynamics, making it particularly useful for applications requiring time-varying soil moisture, such as anomaly detection and memory analyses. SoMo.ml complements the existing suite of modelled and satellite-based datasets given its distinct derivation, to support large-scale hydrological, meteorological, and ecological analyses.

scholarly journals Respiratory Viral Pathogens Among U.S. Military Personnel at a Medical Treatment Facility in Hawaii From 2014 to 2019

2021 ◽  
Author(s):  
Agnes S Montgomery ◽  
Michael B Lustik ◽  
Susan A Reichert-Scrivner ◽  
Ronald L Woodbury ◽  
Milissa U Jones ◽  
...  
Keyword(s):  
Military Personnel ◽  
Influenza A ◽  
Clinical Symptoms ◽  
Medical Center ◽  
Signs And Symptoms ◽  
Military Operations ◽  
Military Population ◽  
Viral Pathogens ◽  
Viral Pathogen ◽  
Medical Treatment Facility

ABSTRACT Introduction Acute respiratory diseases account for a substantial number of outpatient visits and hospitalizations among U.S. military personnel, significantly affecting mission readiness and military operations. We conducted a retrospective analysis of respiratory viral pathogen (RVP) samples collected from U.S. military personnel stationed in Hawaii and tested at Tripler Army Medical Center from January 2014 to May 2019 in order to describe the etiology, distribution, and seasonality of RVP exposure in a military population. Materials and Methods Samples were analyzed by viral culture or multiplex PCR. Distribution of respiratory viruses over time was analyzed as well as subject demographic and encounter data. Presenting signs and symptoms were evaluated with each RVP. Results A total of 2,576 military personnel were tested, of which 726 (28.2%) were positive for one or more RVP. Among positive tests, the three most common viral pathogens detected were influenza A (43.0%), rhinovirus (24.5%), and parainfluenza (7.6%). Symptoms were generally mild and most frequently included cough, fever, and body aches. Conclusion Our study evaluated respiratory virus prevalence, seasonality, and association with clinical symptoms for military personnel in an urban tropical setting in Oahu, HI, over a 5-year period. We show that viral prevalence and seasonality in Hawaii are distinct from those of the CONUS. Results contribute to the broader understanding of seasonality, clinical manifestation, and demographics of RVP among active duty military personnel stationed in Hawaii.

scholarly journals A Study of UVER in Santiago, Chile Based on Long-Term In Situ Measurements (Five Years) and Empirical Modelling

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 368
Author(s):  
Lisdelys González-Rodríguez ◽  
Amauri Pereira de Oliveira ◽  
Lien Rodríguez-López ◽  
Jorge Rosas ◽  
David Contreras ◽  
...  
Keyword(s):  
Urban Areas ◽  
Solar Spectrum ◽  
Sun Exposure ◽  
Great Accuracy ◽  
In Situ Measurements ◽  
Uv Index ◽  
Empirical Modelling ◽  
The People

Ultraviolet radiation is a highly energetic component of the solar spectrum that needs to be monitored because is harmful to life on Earth, especially in areas where the ozone layer has been depleted, like Chile. This work is the first to address the long-term (five-year) behaviour of ultraviolet erythemal radiation (UVER) in Santiago, Chile (33.5° S, 70.7° W, 500 m) using in situ measurements and empirical modelling. Observations indicate that to alert the people on the risks of UVER overexposure, it is necessary to use, in addition to the currently available UV index (UVI), three more erythema indices: standard erythemal doses (SEDs), minimum erythemal doses (MEDs), and sun exposure time (tery). The combination of UVI, SEDs, MEDs, and tery shows that in Santiago, individuals with skin types III and IV are exposed to harmfully high UVER doses for 46% of the time that UVI indicates is safe. Empirical models predicted hourly and daily values UVER in Santiago with great accuracy and can be applied to other Chilean urban areas with similar climate. This research inspires future advances in reconstructing large datasets to analyse the UVER in Central Chile, its trends, and its changes.

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