Eutrombicula cochinocaensis infestation in llamas (Lama glama) in the Puna region of Argentina.

This paper aims to describe a case of trombiculosis in llamas from the Puna region of Argentina caused by Eutrombicula cochinocaensis. Trombiculosis is a parasitic infestation caused by the larval form of trombiculid mites, commonly known as chigger mites. Six adult llamas out of eighteen (33%) were infested and showed dermatitis, hyperemia, and crusts together with an orange-dotted pattern. The chigger mites were found mainly in the hind limbs and the abdomen. Microscopic identification of E. cochinocaensis was made by phase-contrast microscopy. Then, a histopathological study of the affected animals' skin was performed. Histological findings included dermatitis withmainly lymphocytic infiltrate, pustules, crusts, hyperkeratosis, and the mites' stylostomes in the dermis and epidermis. This is the first report of trombiculosis caused by E. cochinocaensis in llamas from Argentina. Mites of the family Trombiculidae are vectors of certain diseases to humans and animals and are therefore of sanitary and productive importance.

Chigger mite (Acariformes: Trombiculidae) infestation in reed passerine birds in Central Europe: a case of the bearded tit Panurus biarmicus.

Larval trombiculid (chigger) mites are common ectoparasites of terrestrial vertebrates including humans, causing itching and skin inflammation known as trombiculiasis. Investigation of their diversity, distribution and seasonal abundance is therefore important from a veterinary and public health point of view. Although researchers have paid increased attention to these parasites in recent years, there is still little ecological data available on chiggers associated with birds inhabiting different types of habitats such as wetlands, for example. In 2021, we investigated the mite fauna in a specialist reedbed passerine, the bearded tit (Panurus biarmicus), and their effects on this host in the south-west Slovakia, Central Europe. A total of 1134 larvae of 1 mite species Blankaartia acuscutellaris were found in 99 out of 267 examined bearded tits. Juveniles were more infested than adult birds, but no differences were found between sexes. The larvae of mites first appeared on the host during the second half of June and peaked in the second half of July. After that, their numbers decreased gradually until October. Despite the relatively high prevalence and intensity of mite infestation in the bearded tit, no differences in body condition between infested and uninfested birds suggest that infestation by B. acuscutellaris may not have serious negative effects on the host health. Bearded tits can therefore be a reliable indicator of the presence of the chigger mites in wetland habitats.

Euschoengastia pipistrelli (Acari: Trombiculidae) from American Perimyotis, Perimyotis subflavus (Chiroptera: Vespertilionidae): Novel Stereoscopic and Scanning Electron Microscopy.

The chigger, Euschoengastia pipistrelli Brennan, is a trombiculid mite that infests a variety of vespertilionid bats in North America. It has been reported from at least 9 species of bats from 18 U.S. states. However, nothing is available on the actual in situ infestation and ultrastructure of this chigger. Here we document some stereoscopic photographs of the infestation as well as a scanning electron micrograph of the mite from a common bat species. We also provide a summation of host and state records for this chigger.

First record of Eutrombicula tinami (Oudemans, 1910) (Trombidiformes: Trombiculidae) parasitizing a cat in Brazil.

Chigger mites are ectoparasites of terrestrial tetrapods and can cause dermatitis in the host, known as trombiculiasis. In Brazil, there are 73 species of chiggers; however, cats never have recorded as a host in this country. Here, we report the first record of chiggers parasitizing a domestic cat in Brazil; and a new locality for Eutrombicula tinami (Oudemans 1910) in the Rio Grande do Sul state, Brazil.

Pathology of Trombiculosis caused by Neoschoengastia simonovichi in Wild Red-Legged Partridges (Alectoris rufa).

Lesions caused by trombiculid mite larvae ('chiggers') in birds have been inadequately described. A juvenile red-legged partridge (Alectoris rufa) presented with multifocal, crater-like lesions of necrotizing dermatitis, which often contained multiple orange mites. Microscopically, there was a nodular necrotizing and pyogranulomatous dermatitis with occasional intralesional arthropods. Histologically, the mites were readily identified by the presence of stylostomes within the necrotic areas. Morphological and morphometrical studies on isolated mites identified them as Neoschoengastia (Hypogastia) simonovichi. This is the first report of N. simonovichi as an aetiological agent of severe trombiculosis in wild birds in Western Europe. Infestation with this parasite requires further study to understand its role in animal and human trombiculosis and its potential role as a vector of infectious, including zoonotic, agents.

Trombiculiasis in a Dog with Severe Neurologic Disorders, Spain.

Chiggers, the larvae of trombiculid mites, parasitize a wide variety of terrestrial vertebrates worldwide. Their bites cause seasonal trombiculiasis in humans and animals. Affected canines can have a variety of digestive and systemic clinical signs. We describe a case of canine trombiculiasis in a dog exhibiting severe neurologic symptoms.

Severe Trombiculiasis in Hunting Dogs Infested With Neotrombicula inopinata (Acari: Trombiculidae).

This study records the clinical findings in nine hunting dogs showing systemic illness associated with trombiculids and identifies the mite species involved. In fall, coinciding with the seasonality of mites, all dogs were infested with mites and had been in the risk area (Sierra Cebollera Natural Park, La Rioja, Spain) a few hours before the onset of symptoms. The symptoms included vomiting, anorexia, weakness and lethargy, diarrhea, and even stupor. The clinical picture was fast-acting and potentially fatal. The infestations varied from low to severe. Molecular analysis of mites that fed on the dogs confirmed that they were larvae of Neotrombicula inopinata (Oudemans, Acari, Trombiculidae). This is the first time that N. inopinata has been identified as feeding on dogs and implicated in canine systemic illness associated with trombiculids. In contrast to other chiggers, N. inopinata does not seem to cause dermatitis. Likewise, the clinical and epidemiological similarity between the clinical symptoms we describe herein and the occurrence of seasonal canine illness (SCI) led us to suspect that this illness may be caused by infestation with these mites. The condition could be the consequence of severe infestation from large numbers of feeding mites, especially N. inopinata. Whether or not the cases were due to a severe allergic host response to salivary proteins or the result of the transmission of a new or emerging trombiculid-borne pathogen is not known.

First report of Neotrombicula inopinata infestation in domestic cats from Portugal.

Trombiculids parasitize a wide variety of terrestrial vertebrates, including domestic animals, throughout the world. They are parasites only during their larval stages, causing several dermatological lesions on their hosts, such as acute dermatitis, erythema, excoriation, erosion, papules, crusts and alopecia on the ear margins, face, interdigital spaces and abdomen. Neotrombicula is one of the several genera in Trombiculidae family, which cause trombiculosis. The most common species implicated in clinical cases is Neotrombicula autumnalis. However, several reports have shown that Neotrombicula inopinata (Oudemans, 1909) can also play a role in trombiculosis. Here, we describe the first case of N. inopinata infestation in domestic cats from mainland Portugal. Since nucleic acids of Anaplasma phagocytophilum and Borrelia burgdorferi have been found in Neotrombicula autumnalis and Rickettsia spp. in Neotrombicula inopinata, a correct taxonomical identification is essential to understand the role of these mite species as possible vectors of pathogens.

Pathology and Distribution of Trombiculosis in Northern Chamois ( Rupicapra rupicapra rupicapra) in the Italian Alps.

Trombiculosis has been reported in some wild ruminant species. We investigated the occurrence of trombiculosis in the northern chamois ( Rupicapra rupicapra rupicapra) in the Western Italian Alps, and we describe the related histopathologic changes. Superficial scrapes and skin samples were taken from 191 chamois from the Lombardy and Piedmont regions during the hunting season in September-December 2015. Numbers of eosinophils, mast cells, cluster of differentiation (CD)3-, CD79α-, CD68-positive cells were determined on immunohistochemically stained skin sections using a semiautomatic analysis system. Forty (20.9, 40/191) chamois were positive for trombiculid larvae on skin scrapings. Of the positive animals, 15 were from Lombardy and 25 from Piedmont, with similar prevalences. Macroscopic lesions were light with involvement of body regions that had contact with the ground, especially head (pinnae and areas around eyes and mouth) and limbs, where stylostome was easily formed due to thin skin. Histologically, trombiculosis caused a focal moderate dermatitis with epidermal necrosis, thin crusts, and hyperkeratosis. Inflammatory infiltrates were suggestive of a granulomatous reaction centered on a stylostome, formed by mite saliva and necrotic host tissue debris. However, we detected some difference in cutaneous immune response with some chamois showing a prevalent T-cell response and others having an increased B-cell count associated with a higher number of eosinophils, mast cells and a lower number of T cells.

High prevalence of chigger mite infection in a forest-specialist frog with evidence of parasite-related granulomatous myositis.

Amphibians are hosts for a wide variety of micro- and macro-parasites. Chigger mites from the Hannemania genus are known to infect a wide variety of amphibian species across the Americas. In Chile, three species (H. pattoni, H. gonzaleacunae and H. ortizi) have been described infecting native anurans; however, neither impacts nor the microscopic lesions associated with these parasites have been described. Here, we document 70% prevalence of chigger mite infection in Eupsophus roseus and absence of infection in Rhinoderma darwinii in the Nahuelbuta Range, Chile. Additionally, we describe the macroscopic and microscopic lesions produced by H. ortizi in one of these species, documenting previously undescribed lesions (granulomatous myositis) within the host's musculature. These findings highlight that further research to better understand the impacts of chigger mite infection on amphibians is urgently required in Chile and elsewhere.

Ectoparasitism by Chigger Mite Larvae (Acari: Trombiculidae) in a Wintering Population of Catharus ustulatus (Turdidae) in Southeastern Peru.

We document chigger mite (Acari: Trombiculidae) ectoparasitic infestation (prevalence and intensity) on a population of Catharus ustulatus (Turdidae) wintering at a site (PAD A) in southeastern Peru undergoing development for natural gas exploration. We compare prevalence (i.e., the proportion of individuals infested by chigger mites) and intensity (i.e., the average number of larvae and larvae clusters in infested individuals) at forest edge (<100 m) and interior (>100 m) from PAD A because variations in biotic (e.g., vegetation cover) and abiotic (e.g., relative humidity and temperature) factors are expected to influence chigger mite abundance. Chigger mite prevalence was 100%; all C. ustulatus captured were infested regardless of distance. The range of variation in larvae (2-72 larvae/individual) and cluster intensity (1-4 clusters/individual) did not differ between edge and interior ( P > 0.05), despite differences in herbaceous vegetation cover (UM-W = 180, n = 30, 31; P < 0.01). Ectoparasitic prevalence and intensity in long-distance migratory birds might add risks to an already hazardous journey; because ectoparasitic variation and other selective pressures experienced by individuals at each locality not only may be a cause of within-site mortality, but, by affecting the physical condition of birds, may be carried over to subsequent sites and affect reproductive success and survival. Documenting ectoparasitism at any phase of the life cycle of migrants could improve understanding of population declines of migratory birds.

Infestation by Chiggers ( Hannemania sp.) of Miranda's White-lipped Frog ( Leptodactylus macrosternum) from a Semiarid, Neotropic Region of Brazil.

We identified Miranda's white-lipped frog ( Leptodactylus macrosternum) as a new host for chiggers ( Hannemania sp.). A total of 57 larvae of Hannemania sp. were found on 31 frogs examined from a semiarid region of northeastern Brazil.

Trombiculiasis in domestic goats and humans in the state of Maranhão, Brazil / Trombiculíase em caprinos domésticos e humanos no Estado do Maranhão, Brasil

Abstract Trombiculiasis is an infestation caused by larval mites (chiggers) of the family Trombiculidae. Here, we provide the first report on parasitism by the chigger species Eutrombicula alfreddugesi (Oudemans) and Eutrombicula batatas (Linnaeus) in goats and humans on farms in the state of Maranhão, northeastern Brazil. Severe itching and dermatitis caused by the chiggers' bites were seen. From a total of 779 examined goats, 214 of them showed clinical signs of infestation, as well as family members of three farms of the region. Most of the cases occurred during the rainy season, from March to September.

Resumo Trombiculíase é uma infestação causada por larvas de ácaros da família Trombiculidae. Nós reportamos pela primeira vez parasitismo por ácaros das espécies Eutrombicula alfreddugesi (Oudemans) and Eutrombicula batatas (Linnaeus) em cabras e humanos em fazendas no estado do Maranhão, nordeste do Brasil. Foram observadas dermatite e coceiras severas causadas pelas picadas de trombiculídeos. De um total de 779 cabras examinadas, 214 delas apresentaram sinais clínicos de infestações, assim como membros de três famílias de fazendeiros da região. A maioria dos casos ocorreu durante a estação chuvosa, de março a setembro.

Trombiculiasis in domestic goats and humans in the state of Maranhão, Brazil.

Trombiculiasis is an infestation caused by larval mites (chiggers) of the family Trombiculidae. Here, we provide the first report on parasitism by the chigger species Eutrombicula alfreddugesi (Oudemans) and Eutrombicula batatas (Linnaeus) in goats and humans on farms in the state of Maranhão, northeastern Brazil. Severe itching and dermatitis caused by the chiggers' bites were seen. From a total of 779 examined goats, 214 of them showed clinical signs of infestation, as well as family members of three farms of the region. Most of the cases occurred during the rainy season, from March to September.

Catenotaenia dendritica (Cestoda: Catenotaeniidae) and Three Ectoparasite Species in the Red Squirrel, Sciurus vulgaris, from Cheongju, Korea.

Parasites are recorded from the red squirrel, Sciurus vulgaris, from Cheongju, the Republic of Korea. A total of 5 road-killed squirrels were thoroughly examined for internal and external parasites from November 2011 to May 2014. Total 4 parasite species, including 1 tapeworm and 3 ectoparasite species were recovered. They were morphologically identified as Catenotaenia dendritica (Cestoda: Catenotaeniidae), Hirstionyssus sciurinus, Leptotrombidium pallidum, and Ceratophyllus (Monopsyllus) indages. Among them, C. dendritica and H. sciurinus are recorded for the first time in the Korean parasite fauna. In addition, the possibility that the red squirrel could act as a reservoir host for a zoonotic disease like tsutsugamushi disease with L. pallidum as its vector has been raised.

Seroepidemiological Survey of Zoonotic Diseases in Small Mammals with PCR Detection of Orientia tsutsugamushi in Chiggers, Gwangju, Korea.

Serosurveillance for zoonotic diseases in small mammals and detection of chiggers, the vector of Orientia tsutsugamushi, were conducted from September 2014 to August 2015 in Gwangju Metropolitan Area. Apodemus agrarius was the most commonly collected small mammals (158; 91.8%), followed by Myodes regulus (8; 4.6%), and Crocidura lasiura (6; 3.5%). The highest seroprevalence of small mammals for O. tsutsugamushi (41; 26.3%) was followed by hantaviruses (24; 15.4%), Rickettsia spp. (22; 14.1%), and Leptospira (2; 1.3%). A total of 3,194 chiggers were collected from small mammals, and 1,236 of 3,194 chiggers were identified with 7 species of 3 genera: Leptotrombidium scutellare was the most commonly collected species (585; 47.3%), followed by L. orientale (422; 34.1%), Euchoengastia koreaensis (99; 8.0%), L. palpale (58; 4.7%), L. pallidum (36; 2.9%), Neotrombicula gardellai (28; 2.3%), and L. zetum (8; 0.6%). L. scutellare was the predominant species. Three of 1,236 chigger mites were positive for O. tsutsugamushi by PCR. As a result of phylogenetic analysis, the O. tsutsugamushi strain of chigger mites had sequence homology of 90.1-98.2% with Boryong. This study provides baseline data on the distribution of zoonotic diseases and potential vectors for the development of prevention strategies of vector borne diseases in Gwangju metropolitan area.

Two new species and new records of chiggers (Acari: Leeuwenhoekiidae, Trombiculidae) from birds in Vietnam.

A total of 12 chigger species (Acariformes: Trombiculidae) occurred on 7 bird species in Vietnam. Two new species, namely Neoschoengastia vietnamensis sp. nov. and Hypogastia stekolnikovi sp. nov. are described, figured and compared with similar species placed in relevant genera using differential diagnoses of related species. Figures and diagnosis of Leptotrombidium taiyuanense Tian and Wen, 1984 are added. Odontacarus audy (Radford, 1946), Leptotrombidium allosetum Wang, Liao and Lin, 1981, L. taiyuanense, Leptotrombidium hanseni Traub and Lakshana, 1966, Leptotrombidium kunshui Wen and Xiang, 1984, Leptotrombidium paradux Vercammen-Grandjean and Langston, 1976, Leptotrombidium turdicola Vercammen-Grandjean and Langston, 1976, Neotrombicula elegans Schluger, 1966 and Neoschoengastia longitar-salis Schluger and Belskaya, 1966 were recorded in Vietnam for the first time.

Resistance to Arrenurus spp. Parasitism in Odonates: Patterns Across Species and Comparisons Between a Resistant and Susceptible Host.

Some adult odonates resist parasitism by larval water mites (Arrenurus spp.) with melanotic encapsulation, in which the mite's stylestome is clogged and the mite starves. In summer 2014, we counted the engorged and resisted mites on 2,729 adult odonates sampled by aerial net at 11 water bodies in Greenville Co. and Pickens Co., SC, and tested the hypothesis that the frequency and intensity of resistance correlates with parasite prevalence (the percentage of parasitized hosts). Resistance prevalence (the percentage of parasitized hosts that resisted at least one mite) varied significantly among host species, exceeding 60% for Argia fumipennis(Burmeister) and Celithemis fasciata Kirby but less than 20% for other species. However, neither resistance prevalence nor mean resistance intensity (mean percentage of resisted mites on resisting hosts) correlated with parasite prevalence. We described potential effects of parasitism on host development ofA. fumipennis and Pachydiplax longipennis(Burmeister) by comparing the percent asymmetry of forewing lengths between parasitized and unparasitized individuals. There was no significant difference in asymmetry for either males or females of A. fumipennis, or males of Pa. longipennis(females were not sampled). We also evaluated differences in melanotic encapsulation between A. fumipennis, which readily encapsulates mites in nature, and Pa. longipennis We inserted a 2.0-mm piece of sterile monofilament line into the thorax of captured individuals for 24 h and compared mean gray value scores of inserted and emergent ends using Image-J software. There was no difference in melanotic encapsulation between species.

Should the poultry red mite Dermanyssus gallinae be of wider concern for veterinary and medical science?

The poultry red mite Dermanyssus gallinae is best known as a threat to the laying-hen industry; adversely affecting production and hen health and welfare throughout the globe, both directly and through its role as a disease vector. Nevertheless, D. gallinae is being increasingly implemented in dermatological complaints in non-avian hosts, suggesting that its significance may extend beyond poultry. The main objective of the current work was to review the potential of D. gallinae as a wider veterinary and medical threat. Results demonstrated that, as an avian mite, D. gallinae is unsurprisingly an occasional pest of pet birds. However, research also supports that these mites will feed from a range of other animals including: cats, dogs, rodents, rabbits, horses and man. We conclude that although reported cases of D. gallinae infesting mammals are relatively rare, when coupled with the reported genetic plasticity of this species and evidence of permanent infestations on non-avian hosts, potential for host-expansion may exist. The impact of, and mechanisms and risk factors for such expansion are discussed, and suggestions for further work made. Given the potential severity of any level of host-expansion in D. gallinae, we conclude that further research should be urgently conducted to confirm the full extent of the threat posed by D. gallinae to (non-avian) veterinary and medical sectors.

HISTOPATHOLOGY AND RISK FACTORS ASSOCIATED WITH NEOTROMBICULA MICROTI INFESTATION IN THE ENDANGERED AMARGOSA VOLE (MICROTUS CALIFORNICUS SCIRPENSIS).

The Amargosa vole (Microtus californicus scirpensis) is a profoundly endangered rodent found only in the Central Mojave Desert, Inyo County, California, US. In 2010, severe cases of trombiculiasis, caused by larval Neotrombicula microti mites, were discovered among voles and sympatric small mammals. We evaluated Amargosa voles and sympatric rodents for infestation with N. microti December 2011-November 2012 and evaluated histopathology of ear tissue from 13 actively N. microti-infested Amargosa voles and 10 Amargosa voles with no gross evidence of current or past infestation. Rodents with current infestation had mites visible on tissue, typically ear pinnae, whereas mites were not seen on rodents with presumptive past infestation, but some of these animals had gross tissue scarring and loss consistent with healing from infestation. Ears from infested voles had severe granulocytic and necrotizing dermatitis, most associated with stylostome fragments, whereas few lesions were present in grossly uninfested voles. There was no association between body condition and infestation or severity of lesions. Significantly more voles were infested (37%) with N. microti than sympatric rodents (3%), suggesting that sympatric rodents do not serve as an important source of N. microti exposure to voles. Although this chigger infestation was common and induced severe localized pathology, we did not detect a fitness cost to infestation and recommend further evaluation of the disease to discern its significance in this conservation context.