The isolation and characterization of chitin (CHI) obtained from Vespa velutina (CHIVV) is described. Moreover, a trapping procedure is presented to selectively catch the invasive species. The chitin contents of dry Vespa velutina was observed to be 11.7 %. The physicochemical properties of CHIVV was characterized by Fourier transform infrared spectroscopy (FTIR), solid-state NMR (ssNMR), elemental analysis (EA), scanning electron microscopy (SEM) and thermogravimetric analysis (TG). Obtained CHIVV is close to pure (43, 47% C, 6.94% H, and 6.85% N) and full acetylated with a value of 95.44%. Also, lifetime and kinetic parameters such as activation E and the frequency factor A using model-free and model-fitting methods, were determined. For CHIVV the solid state mechanism that follows the thermodegradation is of type F2 (Random nucleation around two nuclei). Vespa velutina chitin should not be used at temperatures above 60ºC, since its half-life would be only one year, and from an industrial point of view it would not be profitable. Based on certain factors such as the current and probable continued abundance of Vespa velutina and the quality of the product obtained, the invasive Asian hornet is a promising alternative source of chitin.

The yellow-legged Asian hornet (Vespa velutina Lepeletier 1836 (Hymenoptera: Vespidae)) is naturally distributed in China, Southeast Asia and India; however it has since detected outside of its native area, confirmed as being established in South Korea, Europe and Japan. Health risks and deaths caused by the invasive Vespa velutina stings have become a public health concern, being the most common cause of anaphylaxis due to hymenopterans in some European regions. This in turn has led to increased demand from medical practitioners and researchers for Vespa velutina venom for diagnostic and therapeutic purposes. In this study, a straightforward, quick and inexpensive method for obtaining Vespa velutina venom by electric stimulation is described. The venom extracts were analyzed by nuclear magnetic resonance spectroscopy (1H-NMR), confirming the composition of the obtained material. The availability of Vespa velutina venom will lead to improved diagnostic and therapeutic methods, mainly by venom immunotherapy (VIT), in patients allergic to this invasive species.

Asian giant hornet, Vespa mandarinia, is an invasive species that could potentially destroy local honeybee industry in North America. It has been observed to nest in the coastal regions of British Columbia in Canada and Washington State in USA. What is the source population of the immigrant hornets? The identification of the source population can not only shed light on the route of immigration, but also on the similarity between the native habitat and the potential new habitat in the Pacific Northwest. We analyzed mitochondrial COX1 sequences of specimens sampled from multiple populations in China, South Korea, Japan and the Russian Far East. V. mandarinia exhibits phylogeographic patterns, forming monophyletic clades for 16 specimens from China, six specimens from South Korea and two specimens from Japan. The two mitochondrial COX1 sequences from Nanaimo, British Columbia are identical to the two sequences from Japan. The COX1 sequence from Blaine, Washington State, clustered with those from South Korea, and is identical to one sequence from South Korea (GenBank accession MN716828). Our geophylogeny, which allows visualization of genetic variation over time and space, provides evolutionary insights on the evolution and speciation of three closely related vespine species (V. tropica, V. soror and V. mandarinia). The geophylogeny also highlights a strong insufficiency in sample collection in China. The existing sequenced specimens from mainland China with geographic coordinates were represent only four provinces, missing populations along the coastal regions in East China. One therefore cannot exclude the possibility that the Asian giant hornet found in Canada and USA may also be identical to V. mandarinia in Eastern China. We strongly recommend more extensive DNA barcoding data with geographic information and longer DNA barcode (e.g., the entire mitochondrial genome) so that critical questions on invasive species and environmental conservation can be addressed more accurately than what is possible with existing data.

Epidemiology of fatalities in Spain due to hornet, wasp and bee stings (Cause Code of Death: X23) is described. Over a 20-year period (1999-2018), a total of 78 fatalities were recorded, mostly occurring in males (85.9%), of 65 years and older (52.6%), at “unspecified places” (67.9%) and in the months of July and August (50%). The X23 mortality rates (X23MR) expressed in terms of annual rates and per million inhabitants, varied from 0.02 to 0.19 (mean value ± standard deviation = 0.09 ± 0.05), placing Spain at low levels in comparison with other countries. A more detailed and specific breakdown of the distribution of the yearly deaths at Sub-state level and across communities reveals some striking features. They were more concentrated in the Communities of Galicia (35.8%), Andalucía (21.7%) and Castilla y León (12.8%). X23MR were estimated in Galicia at 1.82, 1.10 and 2.22 in 2014, 2016 and 2018 respectively; and in Asturias at 1.88 and 0.97, in 2014 and 2017 respectively. The role of the invasive species Vespa velutina (VV), is examined. Due to its habits, abundance and broader distribution, the risk that VV represents to human health is unmatched by other Hymenoptera native species.

This study aimed to investigate the venom sac extracts (VSE) of the European hornet (EH) Vespa crabro (Linnaeus, 1758) (Hymenoptera: Vespidae), focusing on the differences between stinging females, gynes (G) and workers (W), at the protein level. Using a quantitative “Sequential Window Acquisition of all Theoretical Fragment Ion Mass Spectra” (SWATH-MS) analysis, we identified and quantified a total of 240 proteins. Notably, within the group, 45.8 % (n = 110) showed significant differential expression between VSE-G and VSE-W. In this set, 57.3 % (n = 63) were upregulated and 42.7 % (n = 47) downregulated in the G. Additionally, the 200 quantified proteins from the class Insecta belong to 16 different species, six of them to the Hymenoptera/Apidae lineage, comprising seven proteins with known potential allergenicity. Thus, phospholipase A1 (Vesp v 1), phospholipase A1 verutoxin 2b (VT-2b), hyaluronidase A (Vesp v 2A), hyaluronidase B (Vesp v 2B), and venom allergen 5 (Vesp v 5) were significantly downregulated in the G, and vitellogenin (Vesp v 6) was upregulated. Overall, 46 % of the VSE proteins showed differential expression, with a majority being upregulated in G. Data are available via ProteomeXchange with identifier PXD047955. These findings shed light on the proteomic differences in VSE between EH castes, potentially contributing to our understanding of their behavior and offering insights for allergy research.