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The small hive beetle (SHB), Aethina tumida Murray, native to sub-Saharan Africa, is a parasite of Apis mellifera causing significant damage to honey bee colonies. For the past decades, it has spread to many countries worldwide and once established, eradication is difficult or not feasible. In July 2022, an outbreak was reported for the first time in a French department in the Indian Ocean, Reunion Island. The origin and the pathway of the introduction were not identified. The molecular characterisation of SHB specimens collected in the southern part of the island, where the beetle has infested several apiaries, was investigated in order to provide elements on the invasive source. The sequencing of the partial Cytochrome oxidase I gene from two specimens showed that they belonged to the same new haplotype. Phylogenetic analysis suggests an introduction either from an unidentified African source or from the Asian continent since the haplotype is similar to those characterized from China and Philippines. [ABSTRACT FROM AUTHOR]

BACKGROUND: Varroa destructor is a parasitic mite of the honey bee, Apis mellifera. Its presence in colonies can lead to a collapse within a few years. The use of acaricides has become essential to manage the hive infestation. However, the repeated and possibly incorrect use of acaricide treatments, as tau‐fluvalinate, has led to the development of resistance. The in vitro phenotypic test allows the proportion of susceptible or resistant individuals to be known following an exposure to an active substance. In Varroa mites, resistance to tau‐fluvalinate is associated with the presence of mutations at the position 925 of the voltage‐gated sodium channel (VGSC). RESULTS: Here, we compared the results obtained with an in vitro phenotypic test against tau‐fluvalinate and those obtained with an allelic discrimination assay on 13 treated and untreated Varroa populations in France. The correlation between the phenotype and the genetic profile rate is found to be 0.89 Varroa mites having resistant phenotypic profile have a probability of 63% to present the L925V mutation (resistance detection reliability). However, 97% of the Varroa mites having the susceptible phenotype do not present the L925V mutation (susceptible detection reliability). CONCLUSION: The L925V mutation explains most of the resistance to tau‐fluvalinate in V. destructor in the populations tested. However, other mutations or types of resistance may also be involved to explain the survival of Varroa mites in the phenotypic test. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In alpine pasture, interspecies transmission has recently been incriminated in the epidemiology of pestivirus infection. The aim of this study was to investigate pestivirus infections in wild and domestic ruminants sharing pastures in the French Southern Alps. Animal sera were screened for pestivirus antibodies against the pestivirus NS3 protein by a commercial blocking enzyme linked immunosorbent assay (ELISA). All 38 domestic herds tested were positive for pestivirus-specific antibodies. Individual sero-prevalence reached 76.5% (95% confidence interval [95% CI]: [74.2–78.8%]) of the 1383 sheep tested. For wild ruminants, 38.7% (95% CI: [33.8–43.9%]) of the 369 chamois tested, 28.7% (95% CI: [17.4–38.1%]) of the 72 roe deer, and 22.2% (95% CI: [6.5–37.9%]) of the 27 mouflons were seropositive. Virus screening was carried out on spleen samples from hunted wild animals ( n = 160) and from 15 domestic ruminants (clinically suspected to be persistently infected animals), by a conventional reverse transcription-polymerase chain reaction (RT-PCR). Three pestivirus strains were isolated from the sheep samples positive by RT-PCR. The viruses were classified in the BDV-3, BDV-Tunisian and BDV-6 genotypes. For the first time, one strain (RUPI-05 strain) was isolated from an alpine chamois and clustered in the BDV-6 genotype, showing in the 5′-UTR region 92% of identity with the ovine isolate from the same area. Thus, an active circulation of pestiviruses was demonstrated in both wild and domestic ungulates from the French Southern Alps. The results suggest that interspecies transmission between sheep and chamois probably occur. [ABSTRACT FROM AUTHOR]

The article discusses a study conducted by researchers Coralie Pulido, Claire Martin and Philippe Gibert from Unité Pathologie des Ruminants and Unité Sanitaire de la Faune in France, to use experimental infection in the investigation of the pathology induced by border disease virus in pregnant chamois from the Pyrenees Mountains. It offers information on the assessment of clinical signs, serology and viremia. It examines the discontinuation of pregnancies and deaths of the animals.

Simple Summary: Aethina tumida, also called the Small Hive Beetle, is an insect that multiplies primarily in honeybee hives, causing honey losses and weakening colonies. It is native to sub-Saharan Africa and was introduced into different countries and continents over the last 20 years, posing a threat to beekeeping internationally. In case of introduction into a new area, officially approved laboratories (certified by government services) carry out analyses to confirm the outbreak. The reliability of the results is essential in the implementation of management measures. Therefore, a study was organised at the European level to compare the results between official laboratories for two types of methods, used routinely for the identification of A. tumida: morphological examination (form and structure) and DNA testing (genetics). The 22 participants analysed in a blinded way a panel of 12 samples (positive and negative samples). The results were very satisfactory, with the exception of one participant who encountered several anomalies for negative samples and especially for DNA tests, probably related to his inexperience with the method. This study proved the ability of laboratories and analytical methods to identify A. tumida, which is a key element in monitoring and managing this risk. The Small Hive Beetle (Aethina tumida Murray, 1867) is an invasive scavenger of honeybees. Originally endemic in sub-Saharan Africa, it is regulated internationally in order to preserve the areas still free from this species. To ensure the reliability of official diagnoses in case of introduction, an inter-laboratory comparison was organised on the identification of A. tumida by morphology and real-time PCR. Twenty-two National Reference Laboratories in Europe participated in the study and analysed 12 samples with adult coleopterans and insect larvae. The performance of the laboratories was evaluated in terms of sensitivity and specificity. Sensitivity was satisfactory for all the participants and both types of methods, thus fully meeting the diagnostic challenge of confirming all truly positive cases as positive. Two participants encountered specificity problems. For one, the anomaly was minor whereas, for the other, the issues concerned a larger number of results, especially real-time PCR, which probably were related to inexperience with this technique. The comparison demonstrated the reliability of official diagnosis, including the entire analytical process of A. tumida identification: from the first step of the analysis to the expression of opinions. The performed diagnostic tools, in parallel with field surveillance, are essential to managing A. tumida introduction. [ABSTRACT FROM AUTHOR]

Nosemosis is a microsporidian disease causing mortality and weakening of honey bee colonies, especially in the event of co-exposure to other sources of stress. As a result, the disease is regulated in some countries. Reliable and harmonised diagnosis is crucial to ensure the quality of surveillance and research results. For this reason, the first European Interlaboratory Comparison (ILC) was organised in 2017 in order to assess both the methods and the results obtained by National Reference Laboratories (NRLs) in counting Nosema spp. spores by microscopy. Implementing their own routine conditions of analysis, the 23 participants were asked to perform an assay on a panel of ten positive and negative samples of crushed honey bee abdomens. They were asked to report results from a qualitative and quantitative standpoint. The assessment covered specificity, sensitivity, trueness and precision. Quantitative results were analysed in compliance with international standards NF ISO 13528 (2015) and NF ISO 5725-2 (1994). Three results showed a lack of precision and five a lack of trueness. However, overall results indicated a global specificity of 98% and a global sensitivity of 100%, thus demonstrating the advanced performance of the microscopic methods applied to Nosema spores by the NRLs. Therefore, the study concluded that using microscopy to detect and quantify spores of Nosema spp. was reliable and valid. • The ILC objective was to test the accuracy of the methods for counting Nosema spores. • EU-NRLs methods were based on the same principle set out in OIE Terrestrial manual. • The results of the 23 participants showed a good specificity, sensitivity, trueness and precision. [ABSTRACT FROM AUTHOR]