[Insect venom allergies-What will change in times of global change?]

BACKGROUND

In Germany, honeybees (Apis mellifera) and various Vespula species (wasps) are primarily relevant for hypersensitivity reactions to stings. Hornets (Vespa crabro), bumblebees, paper wasps (Polistes) and yellowjackets (Dolichovespula) less frequently cause sting reactions.

OBJECTIVE

What effects do intensive agricultural utilization and climate change have on the living conditions and occurrence of Hymenoptera and what consequences do they have for the diagnostics and treatment of hypersensitivity reactions to Hymenoptera stings.

MATERIAL AND METHODS

A literature search was carried out.

RESULTS

Honeybees and wild bees are endangered due to introduced diseases, invasive species and pesticides. The aim of widespread beekeeping activity is to protect honeybees, which is why no reduction in stings is to be expected despite increased bee mortality. In Germany, there is evidence of the spread of thermophilic Polistes species (paper wasps) from south to north and the immigration of Vespa velutina nigrithorax (Asian hornet). It is unlikely that these species will lead to a significant increase in sting reactions. Nests of the red fire ant (Solenopsis invicta), which was originally common in South America, were first detected in Sicily in 2022. Red fire ants are aggressive insects with a high potential for adverse sting reactions.

CONCLUSION

Invasive insects must be considered as a trigger in the anamnesis and diagnostics. Diagnostics are only available for the detection of Polistes sensitization. Therapeutic allergens can be obtained from other European countries for venom immunotherapy of a Polistes allergy. Due to cross-reactivity, diagnostic and therapeutic allergens from Vespula spp. are used for the diagnosis and treatment of suspected allergies to the Asian hornet.

Behaviour of Vespa velutina nigrithorax (Hymenoptera: Vespidae) under Controlled Environmental Conditions

From its introduction in Europe, Vespa velutina nigrithorax has become an invasive species, since it is a predator of native fruits and insects, most of the latter being honeybees. Despite the knowledge on the life cycle of this hornet, Asian hornet behaviour is not well understood, since in vivo studies on this species are quite difficult to perform. In this work, an observational study of the behaviour of this invasive species in captivity has been carried out. Two secondary and one embryo nests were caught and kept under controlled environmental conditions, up to 13 weeks for the secondary nest and 6 weeks for the embryo nest. Captivity adaptation, defence against perturbations, evolution of the colony and overwintering were the different behaviours studied. The study has shown the importance of avoiding disturbances to the nest from the beginning of the experiments, since they tend to destroy the colony. The aggressive behaviour observed in the embryo nest was lower than in the secondary nests. Results of this research will allow obtaining additional information on this species, which is crucial to develop effective control methods.

Vespa velutina nigrithorax venom allergy: inhibition studies approach for the choice of specific immunotherapy

Summary

Vespa velutina nigrithorax (VVN), commonly known as Asian wasp because endemic in Asia, represents an alien species in Europe. VVN can induce allergic reactions similar to those caused by other Hymenoptera and deaths after VVN stings, presumably due to fatal allergic reactions, were reported. In the treatment of Hymenoptera venom hypersensitivity, specific immunotherapy (VIT) is highly effective, and the vaccine allergen-specificity plays a crucial role. Currently, there is no specific available VIT for VVN, so VVN stung patients with severe systemic reactions are treated with Vespula spp (Vspp) venom. It is also relevant to assess if patients stung by VVN and showing allergic reactions could be treated with the Hymenoptera commercially available extracts Vespa crabro (VC) and Vspp, or if they need the specific VIT with VVN venom extract. Our results suggested that both Vspp and VC venoms were able to inhibit the specific IgE for VVN, although the VC venom, compared to the venom of Vspp showed a higher inhibition.

Could Vespa velutina nigrithorax be included in the World Organisation for Animal Health list of diseases, infections and infestations?

Vespa velutina nigrithorax is an invasive alien organism that has raised concerns in all beekeeping communities of invaded countries including the Republic of Korea, European countries and Japan. Known also as the yellow-legged hornet (or the 'Asian hornet'), it is native to northern India, eastern Nepal, Bhutan and the People's Republic of China. Given its climatic and biological characteristics and the effects of climate change, some coastal areas of North America, Argentina, South Africa, Australia and New Zealand are also susceptible to invasion. Vespa velutina nigrithorax notably affects managed honey-bee colonies by predation on foragers and causing a reduction in the collection of food resources. Being a generalist predator, the yellow-legged hornet also preys on other managed and wild pollinators, and therefore its impacts are not limited to the beekeeping sector but also represent a biodiversity concern. The purpose of this paper is to provide an assessment of V. v. nigrithorax against the four criteria established in Chapter 1.2. of the World Organisation for Animal Health (OIE) Terrestrial Animal Health Code for the inclusion of a disease, infection or infestation in the OIE list. The work was requested by the OIE Scientific Commission for Animal Diseases and presented to this Commission and to the OIE Terrestrial Animal Health Standards Commission in September 2017. Owing to the lack of effective measures to prevent its spread, the fact that its legal situation in some countries is under the mandate of environmental authorities rather than Veterinary Services, and because it is not considered a disease or parasite, V. v. nigrithorax is not currently being proposed for inclusion in the OIE list. At the end of the text, the statements from the two commissions are included and discussed.

Nutritional Value of the Larvae of the Alien Invasive Wasp Vespa velutina nigrithorax and Amino Acid Composition of the Larval Saliva

The systematic investigations on the value of social wasps as a food resource are deficient, in spite of the long history of the utilization of social wasps as food and pharmaceutical bioresources. Vespa velutina nigrithorax is an invasive alien wasp species that is currently dominating in East Asia and Europe, bringing huge economic damages. As a control over alien species is made when the valuable utilization of the invasive species as a potential resource are discovered, investigations on the potential of V. v. nigrithorax as a useful bioresource are also in demand. Nutritional and heavy metal analyses of the larvae revealed their balanced and rich nutritional value and safety as a food resource. The larval saliva amino acid composition was investigated for further study on amino acid supplementation and exercise enhancement.

Anaphylaxis to Vespa velutina nigrithorax: Pattern of Sensitization for an Emerging Problem in Western Countries

OBJECTIVE

To define the sensitization pattern of patients with anaphylaxis to Vespa velutina nigrithorax (VVN).

METHODS

We studied 100 consecutive Spanish patients with anaphylaxis to Hymenoptera venom and systematically determined specific IgE (sIgE) to whole venoms (Vespula species, Polistes dominula, Apis mellifera, Vespa crabro, and Dolichovespula maculata) and their molecular components (rApi m 1, rApi m 5, rApi m 10, rVes v 1, rVes v 5, rPol d 5, and cross-reactive carbohydrates). Specific IgE to VVN venom and its antigen 5 (nVesp v 5) were measured in a subsample.

RESULTS

Seventy-seven patients had anaphylaxis to VVN. Of these, only 16 (20.8%) reported previous VVN stings, but were stung by other Hymenoptera. Positive sIgE (>0.35 kUA/L) to each of the whole venoms was detected in >70% of patients (Vespula species in 100%). The components showing >50% positivity were rApi m 5 (51.4%), rPol d 5 (80.0%), and rVes v 5 (98.7%). This pattern was similar to that of Vespula species anaphylaxis (n=11) but different from that of A mellifera anaphylaxis (n=10). Specific IgE to nVesp v 5 was positive in all patients (n=15) with VVN anaphylaxis and was correlated with sIgE to both rVes v 5 (R=0.931) and rPol d 5 (R=0.887).

CONCLUSIONS

VVN has become the commonest cause of Hymenoptera anaphylaxis in our area. Most cases report no previous VVN stings. Their sensitization pattern is similar to that of patients with anaphylaxis to other Vespidae. Specific IgE to antigen-5 from VVN, Vespula species, and P dominula are strongly correlated in patients with VVN anaphylaxis.

Abundance of diet-derived polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in the bodies and nests of the yellow-legged hornet Vespa velutina nigrithorax and risks to human health in South Korea

Detecting polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in an organism's environment is ecologically significant. In particular, the detection of PCDD/Fs in organisms consumed as food suggests the possibility of human health risks. In South Korea, there is a unique custom in which social wasps, such as hornets, have been used as ingredients in traditional liquor. Thus, we investigated the concentrations and patterns of PCDD/Fs for the most common social wasps, the yellow-legged hornet (Vespa velutina nigrithorax), and estimated human health risks based on potential dietary exposure in traditional liquor made from the polluted wasps and their nests. The mean concentration of ∑₁₇ PCDD/Fs in the wasps and nests of V. v. nigrithorax was 33.59 pg/g (median 25.31 pg/g), corresponding to 0.65 pg World Health Organization - Toxic equivalency factor (WHO-TEQ/g) (median 0.49 pg WHO-TEQ/g). The levels of ∑₁₇ PCDD/Fs from the nests of V. v. nigrithorax were higher than those in the adults and larvae. As a result of this risk assessment, the daily intake of traditional liquor made with these wasps and their nests was found to be below safety levels; however, there could still be a possibility for health risks due to the detection of PCDD/Fs from organism. Therefore, continuous monitoring of environmental contaminants, including PCDD/Fs in wasps and nests, is required in order to evaluate human health risks associated with the consumption of traditional liquor made with these biological substances. In addition, the results of this study can be used to calculate dietary exposure to PCDD/Fs and the extent of risk to food in which the organism is consumed.

Moku virus detection in honey bees, Belgium, 2018

We report the detection of Moku virus in honey bees (Apis mellifera) collected in 2017 from hives with a history of attacks by invasive Asian hornets (Vespa velutina nigrithorax) in Belgium. End 2016, Moku virus was reported in Asian hornets from the same area. In addition, the Moku virus was already present in historical samples of bees collected in 2013, that is, 2 years after the official first detection of Asian hornets in the same area of Belgium. This study suggests a spread of Moku virus to honey bees with possible consequences.

Moku Virus in Invasive Asian Hornets, Belgium, 2016

We report the detection of Moku virus in invasive Asian hornets (Vespa velutina nigrithorax) in Belgium. This constitutes an unexpected report of this iflavirus outside Hawaii, USA, where it was recently described in social wasps. Although virulence of Moku virus is unknown, its potential spread raises concern for European honeybee populations.

Complete mitochondrial genome of the yellow-legged Asian hornet, Vespa velutina nigrithorax (Hymenoptera: Vespidae)

The yellow-legged Asian hornet, Vespa velutina nigrithorax, which originated from Asia, has invaded several countries, including South Korea. In Korea, V. velutina nigrithorax predation on honeybees is one of the most serious factors threatening apiculture. We sequenced the complete mitochondrial genome (mitogenome) of V. velutina to better understand the mitogenomic characteristics of this species. The 16,475 bp mitogenome of V. velutina consists of a typical set of genes, with an arrangement identical to that of congeneric species. Vespa velutina possesses the shortest A + T-rich region (132 bp) among congeneric Vespa, and this is also the shortest in the superfamily Vespoidea. Phylogenetic analysis using the 13 protein-coding genes of Vespoidea species indicated that each family forms strongly supported monophyletic groups (Bayesian posterior probability =1; ML, 100%). Moreover, V. velutina and V. bicolor form strongly supported sister groups (Bayesian posterior probability =1; ML, 100%).