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The honey bee (Apis mellifera) parasitic mite, Varroa destructor, is considered one of the main causes of colony losses in European honey bee (EHB) populations around the world. However, some EHB and Africanized honey bee (AHB) populations (derived from the African subspecies A. m. scutellata) that inhabit tropical and subtropical regions of the Americas, have survived varroa mite infestations in the absence of acaricide treatments. It is conceivable to expect that these honey bee populations, which have been subjected to natural selection over decades, would have developed resistance against V. destructor or possess pre-existing adaptations that allow them to survive mite parasitism. Here, we present a comprehensive literature review describing the spread of V. destructor and the honey bee populations occurring in Latin America (LA), and summarize the evidence of resistance of those populations to V. destructor. We also analyze reports describing the potential mechanisms of mite resistance and how they operate in those honey bee populations. Studies of a few EHB, as well as of numerous AHB populations exhibiting resistance to V. destructor in LA, unveil the existence of evolutionary adaptations that restrain V. destructor population growth and provide insight into the current host-parasite relationship. This review supports the notion that selective breeding of local honey bee populations from LA could be a viable strategy to manage varroa mite infestations in colonies. [ABSTRACT FROM AUTHOR]

Bombus pauloensis is a native bumble bee species widely distributed over South America and a key pollinator for native plants and commercial crops. This species is affected by pathogens such as Nosema ceranae, Crithidia bombi and Apis mellifera Filamentous Virus (AmFV). This work aims to document the presence and intensity of exogenous pathogens on the native bumble bee B. pauloensis in different periods of the year during spring and summer. Bumble bees were sampled in four study areas with contrasting land uses to preliminary evaluate if anthropization levels can be related to the presence and intensity of pathogens. DNA was isolated from twenty individuals per sampling site and N. ceranae, C. bombi and AmFV pathogens load were quantified by quantitative PCR. The results showed a wide and ubiquitous prevalence of N. ceranae and C. bombi pathogens in all the sampled bumble bees throughout the year, with a pathogens load that did not differ significantly among the sampling sites. AmFV was undetected in any of the individuals analyzed in any sampling site. This suggests that human activities could equally impact all habitats populated by B. pauloensis. Honey bees were detected with a relevant abundance in all the sampling sites and could be one of the main anthropogenic drivers of pathogens spread and host switches in the analyzed sampling sites. This study analyzes the general occurrence of the prevalence and intensity of the pathogens in a native Argentinian bumble bee species and attempts the correlation with the land use [ABSTRACT FROM AUTHOR]

Managed populations of honey bees (Apis mellifera Linnaeus; Hymenoptera: Apidae) are regularly exposed to infectious diseases. Good hive management including the occasional application of antibiotics can help mitigate infectious outbreaks, but new beekeeping tools and techniques that bolster immunity and help control disease transmission are welcome. In this review, we focus on the applications of beneficial microbes for disease management as well as to support hive health and sustainability within the apicultural industry. We draw attention to the latest advances in probiotic approaches as well as the integration of fermented foods (such as water kefir) with disease-fighting properties that might ultimately be delivered to hives as an alternative or partial antidote to antibiotics. There is substantial evidence from in vitro laboratory studies that suggest beneficial microbes could be an effective method for improving disease resistance in honey bees. However, colony level evidence is lacking and there is urgent need for further validation via controlled field trials experimentally designed to test defined microbial compositions against specific diseases of interest. [ABSTRACT FROM AUTHOR]

Several phytochemicals, such as extracts and essential oils, are among the ecological alternatives that have been studied for the control of pathogens that affect humans, animals, and plants. Essential oils are aromatic oily liquids obtained from plant material and their use to control pathogens is widespread. However, they can have adverse effects when taken in high concentrations. The aim of this study was to evaluate the survival and palatability of a balanced-energy protein diet with the addition of two essential oils, Lippia junelliana (Mold.) Tronc. and Elionorus muticus (Spreng.) Kuntze, in newly hatched worker bees (Apis mellifera L.) during a period of 15 days. Consumption and number of live bees were measured daily for each treatment. For L. junelliana, our results showed a non-toxic trend in long-term survival trials (15 days) at low concentrations. In the case of E. muticus, a toxic effect with low survival was observed at all concentrations. Both essential oils showed good palatability, even at toxic levels. Our results allow us to propose the use of L. junelliana essential oil in field experiments of A. mellifera hives. [ABSTRACT FROM AUTHOR]

Copyright of Ecologia Austral is the property of Asociacion Argentina de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Honey bees (Apis mellifera) pollinate plants in both natural and managed ecosystems, contributing to food production and sustaining and increasing biodiversity. Unfortunately bee depopulation and colony losses are becoming increasingly common worldwide. Several factors contribute to the decline of bee populations, including pathogens (parasites, fungi, bacteria and viruses), ecosystem alteration or loss, and/or agrochemical use. All of these factors alter the defense mechanisms of the bee immune system. Honey bees have an innate immune system that includes physical barriers and generalized cellular and humoral responses to defend themselves against infectious and parasitic organisms. Pathogens, acaricides, fungicides, herbicides and other pesticides affect the bee immune system and consequently bee health. The defense mechanisms of the bee immune system include signaling pathways, pathogen recognition receptors and innate immune system effectors. Although A. mellifera's immune system is very similar to that of Drosophila flies and Anopheles mosquitoes, they possess only about a third of the immune system genes identified in these genera. This relatively low number of genes is probably a consequence that A. mellifera has developed social immunity. This defense strategy lowers pressure on the individual immune system of bees. This review article summarizes and discusses the bases of the honey bee immune system. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Sociedad Entomológica Argentina is the property of Sociedad Entomologica Argentina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Iberoamericana de Micologia is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The bacterium Paenibacillus larvae, the causative agent of American foulbrood disease of honeybee larvae, occurs throughout the world and is found in many beekeeping areas of Argentina. The potential as biocontrol agents of antagonic aerobic spore-forming bacteria isolated from honey samples and other apiarian sources were evaluated. Each isolate was screened against one strain of Paenibacillus larvae (ATCC 9545) by using a perpendicular streak technique. Ten randomly selected bacterial strains from the group that showed the best antagonistic effect to P. larvae ATCC 9545 were selected for further study. These were identified as Bacillus subtilis (m351), B. pumilus (m350), B. licheniformis (m347), B. cereus (mv33), B. cereus (m387), B. cereus (m6c), B. megaterium (m404), Brevibacillus laterosporus (BLAT169), B. laterosporus (BLAT170), and B. laterosporus (BLAT171). The antagonistic strains were tested against 17 P. larvae strains from different geographical origins by means of a spot test in wells. The analysis of variance and posterior comparison of means by Tukey method (P <0.01) showed that the best antagonists were B. megaterium (m404), B. licheniformis (m347), B. cereus (m6c), B. cereus (mv33), and B. cereus (m387). [Copyright &y& Elsevier]

RNA viruses play a significant role in the current high losses of pollinators. Although many studies have focused on the epidemiology of western honey bee (Apis mellifera) viruses at the colony level, the dynamics of virus infection within colonies remains poorly explored. In this study, the two main variants of the ubiquitous honey bee virus DWV as well as three major honey bee viruses (SBV, ABPV and BQCV) were analyzed from Varroa-destructor-parasitized pupae. More precisely, RT-qPCR was used to quantify and compare virus genome copies across honey bee pupae at the individual and subfamily levels (i.e., patrilines, sharing the same mother queen but with different drones as fathers). Additionally, virus genome copies were compared in cells parasitized by reproducing and non-reproducing mite foundresses to assess the role of this vector. Only DWV was detected in the samples, and the two variants of this virus significantly differed when comparing the sampling period, colonies and patrilines. Moreover, DWV-A and DWV-B exhibited different infection patterns, reflecting contrasting dynamics. Altogether, these results provide new insight into honey bee diseases and stress the need for more studies about the mechanisms of intra-colonial disease variation in social insects. [ABSTRACT FROM AUTHOR]

Invasive parasites are major threats to biodiversity. The honey bee ectoparasite, Varroa destructor , has shifted host and spread almost globally several decades ago. This pest is generally considered to be the main global threat to Western honey bees, Apis mellifera , although the damages it causes are not equivalent in all its new host's populations. Due to the high virulence of this parasite and the viruses it vectors, beekeepers generally rely on acaricide treatments to keep their colonies alive. However, some populations of A. mellifera can survive without anthropogenic mite control, through the expression of diverse resistance and tolerance traits. Such surviving colonies are currently found throughout the globe, with the biggest populations being found in Sub-Saharan Africa and Latin America. Recently, genetic differences between mite populations infesting surviving and treated A. mellifera colonies in Europe were found, suggesting that adaptations of honey bees drive mite evolution. Yet, the prevalence of such co-evolutionary adaptations in other invasive populations of V. destructor remain unknown. Using the previous data from Europe and novel genetic data from V. destructor populations in South America and Africa, we here investigated whether mites display signs of adaptations to different host populations of diverse origins and undergoing differing management. Our results show that, contrary to the differences previously documented in Europe, mites infesting treated and untreated honey bee populations in Africa and South America are genetically similar. However, strong levels of genetic differentiation were found when comparing mites across continents, suggesting ongoing allopatric speciation despite a recent spread from genetically homogenous lineages. This study provides novel insights into the co-evolution of V. destructor and A. mellifera , and confirms that these species are ideal to investigate coevolution in newly established host-parasite systems. • Varroa destructor parasites show genetic differences across novel host populations. • Differences can be found in some sympatric populations with different management. • Comparing allopatric populations also revealed ongoing genetic differentiation. • Interactions with distinct host populations appear to drive V. destructor evolution. [ABSTRACT FROM AUTHOR]

• Triatoma Virus may be a candidate for biocontrol of insecticide-resistant triatomines. • TrV was not infective to the beneficial insect Apis mellifera. • TrV does not infect the insect vector Aedes aegypti. Vector control is the most effective method to prevent transmission of Chagas disease. Control is mostly made through chemical insecticides although they have negative impact on wild pollinators, such as bees. Reducing pesticide use through biological alternatives could minimize the damage to these beneficial insects. Triatoma virus (TrV) is a pathogen able to kill triatomines and thus a valid candidate to be used as biological control agent. In this study we evaluate the capacity of TrV to infect an important beneficial insect (Apis mellifera) as well as a plague insect (Aedes aegypti). Results indicate that TrV does not infect the bees or mosquitoes tested in this study. The possible specificity of TrV for kissing bugs reinforces the possible use of TrV as a biological control agent for triatomines. [ABSTRACT FROM AUTHOR]

Rhinosporidiosis is caused by Rhinosporidium seeberi, a parasitic organism of the family Rhinosporideacea family, class Micomycetozoa. The disease is endemic in India; however, some cases were reported in Europe, Africa, North America, and South America. The aim of the present study is to report three cases of rhinosporidiosis in wild horses in different cities of Buenos Aires province, Argentina. We confirm the presence of R. seeberi in the analyzed samples using histopathological and PCR sequencing techniques., (Copyright © 2021 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.)

A 2-year-old female Border collie was examined for dermatitis with a partial alopecic zone around her left front member. Six months later the lesion became swollen, alopecic with ulcerated areas. Microscopy analysis of samples showed numerous non-septate, branching, thin-walled and irregular shaped hyphal elements. Fungal cultures and molecular studies identified Saksenaea vasiformis. Treatments with griseofulvin, itraconazole and surgical debridement were used, however, fourteen months later the dog was euthanatized because of the unfavorable clinical outcome.

American foulbrood (AFB) is a bacterial disease caused by the spore-forming, grampositive bacterium Paenibacillus larvae, which affects honeybee broods worldwide. The aim of this work was to compare the Epsilometer test (Etest) to the agar dilution method for testing a collection of 22 P. larvae strains to tetracycline by using MYPGP and Iso- Sensitest agars. Results showed that a categorical agreement of 100% was found when using Iso-Sensitest, while a categorical agreement of 86.36% was found (with 3 minor errors) when MYPGP was tested. In conclusion, the Etest could be a rapid and reliable method for testing MIC values of tetracycline in P. larvae only when used in combination with Iso-Sensitest agar. Nevertheless, these results should be confirmed with future studies involving a larger number of isolates., (Copyright © 2013 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.)

Honey bee mortality has recently been associated with Israeli acute paralysis virus (IAPV), a proposed etiological agent for a new syndrome known as Colony Collapse Disorder. Bees infected with this virus show shivering wings, progress into paralysis, and finally die outside the hive. During the last years, honey bee mortality became a serious problem for Argentinean beekeepers. We herein report the preliminary results of a survey carried out to detect IAPV in samples taken from several Argentine provinces, by using a reverse transcription Polymerase Chain Reaction assay. Our data indicate the existence of high frequency of IAPV in asymptomatic hives of Argentina.