Search Results (106)

Varroa destructor, an ectoparasitic mite of honey bees, is a major contributor to global colony declines. To manage infestations, beekeepers frequently apply both synthetic and organic miticides—sometimes in combination. While much attention has been given to foragers’ pesticide exposure, nurse bees are also at risk due to direct miticide contact and prolonged exposure to residuals in hive matrices. Despite this, little is known about the effects of sequential miticide applications on nurse bees. In this study, we evaluated the toxicities of single and pairwise consecutive applications of three synthetic miticides (fluvalinate, coumaphos, and amitraz) and two organic miticides (formic acid and oxalic acid) at field-realistic concentrations. Miticides were topically applied to nurse bees with 24 h between consecutive treatments. Synthetic miticides caused minimal mortality, while both organic miticides—especially formic acid—significantly reduced survivorship. Consecutive treatments generally produced mortality rates comparable to that of the corresponding organic miticide alone, indicating that observed toxicities were primarily driven by the organic agents. Notably, the fluvalinate–formic acid combination induced no significant adverse effects. These findings highlight the need for caution when using miticides in combination and support the development of safer application strategies to protect vulnerable in-hive bee populations.. Full article

Honey bees (Apis mellifera) play a crucial role in global food production through the pollination of various crops. These vital insects are susceptible to a range of viral pathogens that can disrupt their normal behavior and physiology, ultimately affecting colony dynamics and survival. There are diverse viruses that infect honey bees at different life stages, with a year-round prevalence. There are multiple pathways through which viruses can be transmitted among colonies. Notably, there is also a lack of commercial treatments against viral infections in bees, but some promising strategies exist to mitigate their negative effects, including vector control, and the implementation of good beekeeping practices and biosecurity measures. While methods for treating infected colonies have garnered attention, they receive less focus compared to aspects like transmission methods and seasonal prevalence of viruses. This article aims to review the aforementioned strategies in light of the available literature. It presents succinct and practical approaches categorized based on their potential direct or indirect effects on viruses, providing beekeepers and researchers with an overview of both fully established and still-developing methods. Controlling the ectoparasitic Varroa destructor mite population, which significantly impacts viral prevalence and virulence in bees, is crucial for reducing infections. Practical approaches such as selectively breeding honey bee populations resistant to viruses and ensuring proper nutrition are important strategies. Moreover, genetic methods have also been proposed and tested. The article not only emphasizes these methods but also discusses knowledge gaps and suggests future solutions to improve the health and productivity of honey bee colonies. Full article

Dermanyssus gallinae, Ornithonyssus sylviarum, and Ornithonyssus bursa are ectoparasitic bird mites that affect both avian hosts and humans, causing economic losses in poultry farming and dermatological issues in humans. Due to their small size and transient feeding behaviour, mite-induced dermatitis is often misdiagnosed. In this study, over 4900 cases of entomodermatoses, recorded at the Urania Research Centre and the Department of Veterinary Medicine of Perugia—Parasitology Section between 2010–2024, were analysed, selecting cases linked to bird mites. Data on lesion onset, timing, infestation location, environmental factors, lesion type, and symptoms were examined. Avian Dermanyssoidea mites were responsible for about 4% of dermatological cases, with D. gallinae and O. sylviarum being the most prevalent, while O. bursa was less frequent. Species identification was also based on the morphology of the chelicerae and palps, with cases peaking in spring and summer. These mites were widely distributed across Italy, and Ornithonyssus species caused more severe skin reactions than Dermanyssus. Infestations often involved both genera. This study provides the first large-scale analysis of bird mite infestations in Italy, offering new insights into their distribution, infestation dynamics, and clinical symptoms. The findings contribute to improving diagnostic accuracy, pest control strategies, and public health interventions. Full article

Chiggers (chigger mites) and gamasid mites are two groups of ectoparasites on rodents, and they can be the vectors or potential vectors of scrub typhus and hemorrhagic fever with renal syndrome (HFRS), while Bower’s white-toothed rat (Berylmys bowersi) can serve as the reservoir host of the diseases. Based on field investigations at 117 survey sites of southwest China, a total of 2512 mites were collected from 55 B. bowersi rats. Under a microscope, these mites were taxonomically identified as 56 distinct species, comprising 37 chigger mite species and 19 gamasid mite species. The mite infestation burdens on B. bowersi were heavy, with a high prevalence (P_M = 85.45%), mean abundance (MA = 45.67), and intensity (MI = 53.45). Of 56 mite species identified, 7 are vectors of scrub typhus and HFRS. Of the seven vector mite species, Leptotrombidium scutellare was one of dominant chigger species, with a higher infestation index on rats (P_M = 21.82%, MA = 7.76) than the other six vector mite species. The sex ratio of female gamasid mites was higher than that of males. The number and infestation of adult gamasid mites were higher than those of immature mites. The infestation indexes of mites on B. bowersi hosts varied with the host’s sex and age and fluctuated along different environmental gradients. The association coefficient (V) showed a slight positive association between chiggers and gamasid mites, suggesting that these two groups of mites may coexist on B. bowersi rats. Spearman correlation coefficients showed positive correlations among some dominant and vector mite species, indicating that some mite species tend to select the same hosts. A total of 69 mite species (47 chigger mite species and 22 gamasid mite species) on B. bowersi were estimated by species rarefaction and extrapolation curves. In conclusion, Berylmys bowersi has a high susceptibility to mite infestation, and it has the potential to harbor abundant mites, with heavy mite burdens. The occurrence of vector mite species, especially L. scutellare (the dominant species), increases the potential risk of transmission and the focus persistence of scrub typhus and HFRS in southwest China. Full article

Feline parasitism affects animals’ health and welfare. Faeces from 472 client-owned cats from Greece were examined to provide updated data on the epizootiology of metazoan endo- and ectoparasites (namely, Toxocara cati, Ancylostomatidae, Dipylidium caninum, lungworms, Toxascaris leonina, Otodectes cynotis, fleas, ticks and Notoedres cati). All positive animals received a topical formulation containing esafoxolaner, eprinomectin and praziquantel (NexGard^® Combo, Boehringer Ingelheim), and its efficacy was evaluated. The overall prevalence of parasitism was 22.9%, while that of multiparasitism was 16.3%. Toxocara cati (18.4%) was the most prevalent endoparasite, followed by Ancylostomatidae (10.8%), D. caninum (4.7%), lungworms (2.5%) and T. leonina (0.4%). Regarding ectoparasites, O. cynotis (3.2%), fleas (2.3%), ticks (0.6%) and N. cati (0.4%) were found. To estimate the efficacy of treatment, the geometric means of the number of parasitic elements before the first treatment and post-treatment, (i) 14 days for intestinal helminths, (ii) 28 and 56 days for lungworms and (iii) 28 days for O. cynotis and fleas, were estimated and compared. Following statistical analyses (paired t-test and McNemar’s test), an efficacy of 100% was recorded against the most commonly detected parasites (gastrointestinal helminths and mites) and a notable statistically significant effect against fleas and lungworms after one dose, while 100% efficacy against lungworms was achieved after two doses of the product. No adverse effects were reported. The prevalence of parasitism in owned cats in Greece remains high, highlighting the demand for targeted preventive antiparasitic schemes. This study demonstrated high-level efficacy and tolerance of NexGard^® Combo against common endoparasites and ectoparasites of household cats in Greece. Full article

Bats (Chiroptera) are among the most diverse and geographically dispersed mammals. They are of great importance to the ecosystem, as pollinators, seed dispersers and pest controllers, in addition to being hosts to several parasitic arthropods, including ticks, mites, lice, fleas and flies. Their diet includes the tissue and blood or other body fluids of bats. Bats are reservoirs of several disease-causing agents, many of them pathogenic to humans, such as bacteria, as well as protozoa, viruses and fungi. This study was conducted in Monte Negro, Rondônia, Brazil and the occurrence of parasitic arthropods in bats was evaluated, as well as a screening of bacteria that these ectoparasites can carry. Through a total of 69 nocturnal captures, 217 chiropterans were sampled, representing 23 species and six families. A total of 592 specimens of parasitic arthropods (ticks, mites and flies) were collected from these bats (9% dipterans, 59% ticks and 32% mites). Bartonella spp. were found in two species of bat flies (Trichobius joblingi and Strebla mirabilis) in peri-urban and forest areas with an infection rate of 62% and 38%, respectively. We report for the first time in Rondônia the argasid tick Ornithodoros hasei and its infection by a spotted fever group bacterium ‘Candidatus Rickettsia wissemanii’ in a peri-urban area. Full article

Gamasid mites (Acari: Mesostigmata) are ecologically diverse arthropods, many of which act as vectors for zoonotic diseases such as rickettsial pox and hemorrhagic fever with renal syndrome. This study investigates the faunal and ecological patterns of gamasid mites across five zoogeographic microregions in Yunnan Province, China, a biodiversity hotspot with complex topography. From 1990 to 2022, 18,063 small mammal hosts (primarily rodents) were surveyed, yielding 167 mite species (141,501 specimens). The key findings include the following: (1) Low host specificity: most mite species parasitized >10 host species, with Laelaps nuttalli, L. echidninus, Dipolaelaps anourosorecis, L. guizhouensis, L. turkestanicus, and L. chini dominating (>76.59% abundance). (2) Environmental heterogeneity: mountainous and outdoor habitats exhibited higher mite diversity than flatland/indoor environments. (3) Zoonotic risks: thirteen vector species with low host specificity were identified, potentially amplifying disease transmission. (4) Ecological niche dynamics: high niche overlaps (e.g., Laelaps guizhouensis vs. L. xingyiensis: O_ik = 0.997) and positive interspecific correlations (e.g., L. echidninus vs. L. nuttalli: R = 0.97, p < 0.01) suggest co-occurrence trends on shared hosts. (5) Biogeographic patterns: mite communities were clustered distinctly by microregion, with the highest similarity being obtained between western/southern plateaus (IV and V) and unique diversity in the Hengduan Mountains (I). (6) Chao 1 estimation predicted 203 total mite species in Yunnan, 36 of which were undetected in the current sampling. These results highlight the interplay of biogeography, host ecology, and environmental factors in shaping mite distributions, with implications for zoonotic disease surveillance in biodiverse regions. Full article

Bats and their ectoparasites play a crucial role in understanding the ecology and transmission of vector-borne pathogens, yet these dynamics remain poorly studied in Portugal. This study aimed to investigate the molecular occurrence of vector-borne bacteria (Anaplasma spp., Bartonella spp., Ehrlichia spp., and Rickettsia spp.) and protozoa (Babesia spp. and Theileria spp.) in ectoparasites of cave-dwelling bats. Bats were sampled from two caves in Portugal, and their ectoparasites included wing mites (Spinturnix myoti), ticks (Ixodes simplex), and bat flies (Penicillidia conspicua and Nycteribia schmidlii). Molecular analyses revealed the presence of Bartonella spp. in S. myoti and N. schmidlii. Phylogenetic inference based on the gltA gene positioned the detected genotypes close to those previously reported in bats and Nycteribiidae flies in Europe, Asia, and Africa. Notably, no DNA from Anaplasmataceae, Rickettsia spp., or piroplasmids was detected. The prevalence of S. myoti was high, with all examined bats being infested, showing notable differences in ectoparasite diversity concerning sex and cave-specific location. These findings suggest that host behavior, environmental conditions, and ectoparasite lifecycles play critical roles in shaping pathogen transmission dynamics. This study advances the understanding of bat ectoparasite–pathogen interactions in a region with limited data and highlights the need for continued research to assess the zoonotic potential and ecological impacts of the Bartonella genotypes detected herein. Full article

Quill mites of the family Syringophilidae (Acariformes: Prostigmata) are highly specialised avian ectoparasites that inhabit feather quills. Despite their widespread occurrence, their diversity, distribution, and host associations remain poorly understood. This study examined the diversity and ecological interactions of syringophilid mites parasitising Euphoninae hosts. We analysed 298 dry bird skins representing 25 species deposited in the Bavarian State Collection for Zoology in Munich, Germany. Quill mite infestations were detected in 15 host species, identifying 4 mite species, including 2 newly described taxa: Aulonastus neotropicalis sp. n. and Syringophilopsis euphonicus sp. n. Infestation prevalence ranged from 2% to 25%. Quill mite–host interactions exhibited high specialisation and niche differentiation, with no co-occurring species sharing the same microhabitat. Network analysis indicated moderate connectance (0.35) and significant host specificity (H2′ = 0.77, p = 0.007). Biogeographic history suggests that divergence from Carduelinae and subsequent evolutionary events shaped syringophilid diversity in Euphoninae. These findings underscore the importance of museum collections in uncovering cryptic parasite diversity and provide new insights into host–parasite co-evolutionary dynamics. Full article

Varroa destructor is an ectoparasitic mite that causes a true syndrome with complex symptoms in honeybees. For mite control, several synthetic active principles are commercially available. However, these formulations are proving less effective due to the acquisition of resistance mechanisms by the parasite. Naturally derived compounds, such as essential oils, are less prone to generating resistance mechanisms in mite populations and have been proven effective in numerous independent laboratory investigations. In this study, semi-field and field tests were conducted to evaluate the acaricidal efficacy of two essential oils (Citrus bergamia and Citrus limon), which, in our previous residual contact toxicity tests, showed efficacy against Varroa mites. For semi-field cage tests, two-level cages were set up. Filter paper soaked with different concentrations of essential oils was placed in the lower compartment of the cage; 20 honeybees and 10 Varroa mites were allocated in the upper level. Mite detachment from the honeybees was evaluated after 24 and 48 h. For field tests, cardboard strips soaked with solutions of essential oils at different concentrations were inserted in the experimental hives. Weekly, the strips were replaced, and the fall of parasites on the diagnostic bottom board was assessed. Semi-field tests showed that the essential oils, at the concentrations used, were not toxic to bees. In the semi-field tests, an average acaricidal efficacy of 33% and 60% was obtained, at the highest concentration used, for bergamot and lemon essential oils, respectively. During the 4 weeks of exposure to 600 mL of BEO, the average mite mortality was 28.5%. In the experimental group treated with the intermediate concentration of 1200 mL, the average mite mortality at the end of four weeks was 30.2%, while with the highest concentration of 1800 mL, it was 40.3%. During the four weeks of exposure to 600 mL of LEO, the average mite mortality was 34.1%. In the experimental group treated with the 1200 mL concentration, the average mite mortality at the end of the four weeks was 46.6%, while with the highest concentration, it was 50.7%. This study shows that the acaricidal efficacy observed in field tests differs from that in laboratory tests. Innovative formulations are needed that allow the time-controlled and gradual release of essential oil in the field. Full article

Bird mites are parasites that feed on both wild and domesticated bird species, causing severe degradation in avian welfare. The chicken mite, Dermanyssus gallinae in particular, is a widespread ectoparasite in poultry, responsible for several challenges faced by the poultry industry, including poor animal health, which causes significant economic losses. This review, based on our current knowledge, aims to provide a comprehensive insight into the biology and distribution of these mites, as well as their impact on poultry health and production. It explores the most prevalent mites in avian species, with a focus on D. gallinae, and examines the different psychological and physiological alterations observed in infected stocks, such as decreased egg production, weight loss, and an increased susceptibility to diseases. This review will also cover existing control strategies, including chemical, biological, and environmental approaches, with attention to the growing concern around pesticide resistance. Additionally, it delves into genetic research conducted on these mites, primarily focusing on phylogenetic studies, which have provided insights into their evolutionary relationships and potential vulnerabilities. By compiling existing studies, this article underscores the urgent need for effective and sustainable countermeasures, as well as further genetic research to mitigate the substantial impact of D. gallinae on the poultry sector. Full article

The ambrosia beetle Euwallacea interjectus Blandford (Coleoptera: Curculionidae: Scolytinae) has recently emerged as a pest in Chinese poplar plantations, causing significant economic losses through damage to host trees in association with its mutualistic fungus Fusarium populicola. This study evaluated the biocontrol potential of Beauveria bassiana strain B-BB-1, Serratia marcescens strain B-SM-1, its metabolite prodigiosin, and two ectoparasitic mites, Pyemotes moseri and Pyemotes zhonghuajia. B. bassiana exhibited significant lethality toward adult female E. interjectus, reduced offspring production, and inhibited F. populicola growth. S. marcescens and prodigiosin had certain lethal effects on larvae and inhibited the growth of F. populicola. Both mites effectively parasitized beetle pupae and larvae, with no significant differences in efficacy between the two species. These agents demonstrate promise for the biological control of E. interjectus, offering insights for managing ambrosia beetle infestations. Full article

Olfaction mediated by the antennae is a vital sensory modality for arthropods and could be applied as a tool in pest control. The ectoparasitic mite Varroa destructor poses a significant threat to the health of the honey bee Apis mellifera worldwide and has garnered global attention. To better understand the chemical ecology of this host–parasite relationship, we collected and characterized the volatile organic compounds (VOCs) from V. destructor and used electroantennography (EAG) to record the responses of honey bee (A. c. cerana and A. m. ligustica) antennae to the different VOCs. Fifteen VOCs were detected from V. destructor using gas chromatography–mass spectrometry (GC-MS), which mainly contained ethyl palmitate, followed by isoamyl alcohol, nonanal, and ethyl oleate. The EAGs for ethyl palmitate were higher at the lowest stimulus loading (5 μg/μL in liquid paraffin) in A. c. cerana compared to A. m. ligustica, suggesting that A. c. cerana may have acute sensitivity to low concentrations of some VOCs from V. destructor. After exposure to ethyl palmitate for 1 h, the relative expression levels of AcerCSP1 and AcerOBP21 in A. c. cerana significantly increased, as well as the level of AmelCSP1 in A. m. ligustica, while AmelOBP8 showed no significant changes. The results indicate that the EAG response was influenced by the VOC composition and concentration. A. c. cerana tended to be more responsive than A. m. ligustica to the VOCs of V. destructor. Our findings offer a deeper understanding of how bees recognize V. destructor, potentially using ethyl palmitate as a chemical cue. Full article

Wolbachia is a common intracellular bacterial genus that infects numerous arthropods and filarial nematodes. In arthropods, it typically acts as a reproductive parasite, leading to various phenotypic effects such as cytoplasmic incompatibility, parthenogenesis, feminization, or male-killing. Quill mites (Acariformes: Syringophilidae) are a group of bird parasites that have recently attracted increasing interest due to the detection of unique phylogenetic lineages of endosymbiotic bacteria and potentially pathogenic taxa. Our study used an unbiased 16S rRNA gene amplicon sequencing approach to examine several populations of Namibian quill mites for the presence of bacteria that could affect their biology. We detected Wolbachia in two mite populations collected from two species of larks. However, we did not find any other endosymbiotic bacteria or any that could be of epidemiological importance. Since the mite taxa we tested were previously unknown to science, we conducted comprehensive morphological and molecular systematic analyses on them. Our research revealed two new quill mite species of the genus Syringophilopsis Kethley, 1970 which parasitize three sub-Saharan alaudids, i.e., Syringophilopsis erythrochlamys sp. n. from the dune lark Calendulauda erythrochlamys (Strickland, HE) and S. christinae sp. n. from the Karoo long-billed lark Certhilauda subcoronata (Smith) and spike-heeled lark Chersomanes albofasciata (de Lafresnaye, NFAA). In addition, we provided the African reed warbler Acrocephalus baeticatus (Vieillot, LJP) as a new host for S. acrocephali Skoracki, 1999. Our study expands the knowledge on parasite diversity and provides new insights into Wolbachia infection among quill mites in Africa. Full article

The ectoparasitic mite Varroa destructor is well known for transmitting a number of viruses that can contribute to the collapse of honeybee colonies. To date, the many control measures put in place to limit the spread of V. destructor have yielded no satisfactory results. This is challenging because the effect of the parasite on honeybee colonies is becoming notorious. This has weakened the beekeeping industry and reduced pollination services, which may contribute to global food insecurity in the future. Therefore, it is necessary to put in place possible control measures and outline sustainable approaches to mitigate research efforts against the Varroa destructor. Extensive research to elaborate on the best possible solution has revealed that the selective breeding of naturally occurring V. destructor immune-related traits of honeybee strains is sustainable. Since the Integrated Pest Management approach was introduced, while still being very unreliable, there are open questions as to what control strategy could be considered effective. After cross-examination of existing strategies, a more practical way could be the adoption of an integrated approach. This approach should involve the association of selective breeding of honeybee colonies with V. destructor immune-related traits and the application of soft chemical treatment. Full article