Search Results (34)

Demodex mites are common commensals of mammalian skin, but under certain conditions, they can cause severe skin diseases. This study analyzed the presence, diversity, and phylogenetic relationships of Demodex species in two wolf subspecies from southern Europe to determine whether species-level differences exist between wild and domestic canids after thousands of years of divergence. A total of 1400 hair samples from 140 wolves were analyzed using a real-time PCR (qPCR) targeting mitochondrial 16S rRNA and nuclear 18S rRNA genes. Overall, 37.1% (52/140; 95% CI: 29.0–45.9%) of wolves were positive for Demodex DNA, with a higher prevalence in Italian (46%) than in Iberian (36%) wolves. The lip and chin areas were the most reliable sampling sites. Four Demodex species were identified in wolves: D. injai and D. canis (associated with dogs), and D. folliculorum and D. brevis (associated with humans). Co-infestations involving multiple Demodex species were recorded for the first time in wild canids. These results challenge the long-held belief of strict host specificity in Demodex mites. The discovery of Demodex species associated with both humans and dogs in wolves supports the idea that host-switching and ecological interactions have occurred throughout the evolution of canids and humans. Such cross-species transfers may have taken place during the early domestication of dogs, representing a plausible scenario compatible with our data. However, given the isolated history of the two southern wolf populations, it is more probable that these findings result from recent interspecific transmission events, likely facilitated by ecological overlap with domestic animals and human environments. Future genomic studies will be essential for clarifying the evolutionary relationships within the genus Demodex and its host associations. Full article

Background/Objectives: Demodex mites are a common yet underdiagnosed cause of ocular surface diseases, including blepharitis and meibomian gland dysfunction (MGD). Traditional diagnosis via microscopic examination is labor-intensive and time-consuming. This study aimed to develop a deep learning-based system for the automated detection and quantification of Demodex mites from microscopic eyelash images. Methods: We collected 1610 microscopic images of eyelashes from patients clinically suspected to have ocular demodicosis. After quality screening, 665 images with visible Demodex features were annotated and processed. Two deep learning models, YOLOv11 and RT-DETR, were trained and evaluated using standard metrics. Grad-CAM visualization was applied to confirm model attention and feature localization. Results: Both YOLO and RT-DETR models were able to detect Demodex mites in our microscopic images. The YOLOv11 boxing model revealed an average precision of 0.9441, sensitivity of 0.9478, and F1-score of 0.9459 in our detection system, while the RT-DETR model showed an average precision of 0.7513, sensitivity of 0.9389, and F1-score of 0.8322. Moreover, Grad-CAM visualization confirmed the models’ focus on relevant mite features. Quantitative analysis enabled consistent mite counting across overlapping regions, with a confidence level of 0.4–0.8, confirming stable enumeration performance. Conclusions: The proposed artificial intelligence (AI)-based detection system demonstrates strong potential for assisting ophthalmologists in diagnosing ocular demodicosis efficiently and accurately, reducing reliance on manual microscopy and enabling faster clinical decision making. Full article

The raccoon, Procyon lotor, is an alien species in Europe, where it is considered invasive and poses significant environmental and sanitary risks: it can increase the host reservoir by both introducing new parasites to the region and acquiring native ones. One permanent component of the mammalian parasitofauna is the Demodecidae, highly specific skin mites that often accompany their hosts in various regions of their range. To date, unidentified Demodex species have been found in raccoons within their native range. It has now become important to determine whether raccoons from invasive populations retain their specific parasites during range expansion and potentially spread them or whether they become colonized by other demodecid mites acquired from European mammals. The present analyses of three raccoons identified Demodex procyonis sp. nov. in the skin. This species is distinct from demodecid mites known from other mammals (including European species) but shows similarities in structure and location to mites found on raccoons in the United States. It is therefore likely to be a raccoon-specific species of Demodecidae and the first representative of this mite family described from the family Procyonidae. Full article

The role of Demodex mites in the pathogenesis of skin diseases still needs updating. The aim of the study was to determine the relationship between Demodex sp. infestation and ocular and skin lesions in patients with atopic dermatitis (AD) and psoriasis (PsO). The control group comprised subjects that had not been diagnosed with any inflammatory skin disease. Direct microscopic examination (DME) was applied to analyze eyelashes and skin scraping samples. Demodex mites were detected more often in the eyelash samples than in the skin in both the AD (16.7% vs. 6.7%) and PsO (18.5% vs. 7.4%) patients as well as in the control group (25.8% vs. 3%). The mean intensity of Demodex infestation was 4.25 in the AD patients, 3.4 in the PsO patients, and 2.8 in the control group. Emollients were used in the treatment by 76.7% of the AD patients and 64.8% of patients with PsO; however, this type of skin care did not significantly increase the risk of skin colonization by Demodex. AD and PsO do not seem to facilitate excessive Demodex sp. proliferation. Nevertheless, diagnosis of the presence of these mites should be considered in patients with facial skin and ocular lesions that do not respond to the treatment. Full article

The largest Eurasian rodent, the Eurasian beaver Castor fiber, is known for its amphibious lifestyle that allows it to adapt its environment to its needs. Due to its lifestyle and evolutionary history, the beaver is characterized by a distinct, unique parasitofauna. In this context, the occurrence of mites from the Demodecidae family in the Eurasian beaver was investigated. The topography of the Demodex castoris was analyzed: it was previously known from a single record from a single skin location of this host. The mite was found in large numbers in various locations in the hairy skin, including the head, trunk, and limbs. In addition, a new species associated with hairless skin, mainly around the mouth, was discovered and described: Demodex ovaportans sp. nov. The females of this species carry the egg on the dorsal side of the podosoma, which may be a form of care and a previously unknown reproductive strategy in Demodecidae. Our findings confirm that a host-specific demodecid mite species associated with the hairy skin of the entire body is a universal model in mammals. They also emphasize the uniqueness of the beaver parasitofauna, as evidenced by the host specificity and the different biology of the demodecids described in it. Full article

Herein, we present scanning electron microscopy imagery of Demodex folliculorum on the eyelashes of a patient with a two-year history of dry, burning, and watery eyes. Demodex mites are part of the normal human skin flora, inhabiting hair follicles and sebaceous glands. However, in some individuals, they may contribute to ocular surface diseases, including blepharitis and dry eye disease. Symptoms often include itching, photophobia, and a foreign body sensation. The pathogenic role of Demodex is not fully understood but may involve microabrasions, gland obstruction, hypersensitivity reactions, and bacterial dysbiosis. The presence of collarettes at the base of eyelashes is a diagnostic hallmark. Although optimal treatment remains debated, options include topical tea tree oil, ivermectin, and a recently FDA-approved drug lotilaner. Our patient responded favorably to a two-month regimen of tea tree oil-based eyelid wipes. This case underscores the clinical relevance of Demodex infestation in chronic ocular discomfort and highlights the importance of diagnostics. Full article

Acneiform eruptions are a common adverse effect of lithium treatment that may impact adherence. It is not clear why lithium may worsen these lesions and treatment has focused on traditional treatments for acne. Demodex mites are known to commensurably exist in a large fraction of humans and are known to cause dermatologic conditions in a minority of individuals. An association with acneiform eruptions is well documented but is generally believed to not be causative. We present a hypothesis that lithium treatment may alter the environment of Demodex mites in a fashion that may increase their propensity to cause disease. If that is accurate, treatment with acaricidal agents may be an additional option. Full article

Demodex folliculorum and Demodex brevis are external parasites that reside in human hair follicles and sebaceous glands, most commonly on the cheeks, chin, nose, and eyelids, inhabiting the eyelash follicles. The prevalence of Demodex spp. varies with age. The highest concentration of mites is observed in older people, being almost 100%, and the lowest is found in children. Although the presence of parasites does not directly lead to the development of pathological symptoms, their high density is associated with diseases such as rosacea or blepharitis. This manuscript delves into the biological characteristics of Demodex folliculorum and Demodex brevis with consideration of current diagnostic techniques for detecting Demodex mites. It also aims to provide an in-depth analysis of the role Demodex mites play in the development of various dermatological conditions, with a review of the current therapeutic approaches for managing Demodex-related diseases. Full article

The aim of this study was to determine the subjective ocular symptoms in pre- and perimenopausal women infected with Demodex folliculorum and D. brevis. Eyelashes were taken from pre- and perimenopausal women aged from 45 to 69 years (n = 253) and younger women aged from 3 to 40 (n = 204) from the West Pomeranian Voivodeship located in Poland. The prevalence of mites was analyzed according to age and subjective ocular symptoms. Demodex spp. were detected in 75/253 (29.64%) of pre- and perimenopausal women and in 25/204 (12.25%) of younger women. Demodex folliculorum or D. brevis was observed in 72/252 (28.45%) and 1/253 (0.4%) of pre- and perimenopausal women, respectively, but the coinfection of D. folliculorum and D. brevis was noted in 2/253 (0.79%) of women. In young women, only D. folliculorum was detected. Single Demodex spp., multiple parasites, and numerous mites were reported in about 75%, 17%, and 8% of the examined women, respectively. There was a statistically significant relationship between Demodex spp. infestation and the occurrence of dryness of the eyes. Changes occurring in the female body during the pre- and perimenopausal periods lead to an increased incidence of Demodex spp. infestation. Women who report dryness of the eyes should have their eyelashes microscopically examined for Demodex spp. Full article

Background/Objectives: Blepharitis is a condition often caused by Demodex folliculorum infestations, resulting in significant ocular discomfort and surface damage. Current treatments offer only temporary relief and fail to eliminate mites effectively. This study evaluates nano-niclosamide (nano-NCL), a lipophilic nanosuspension designed to enhance solubility and permeability, for targeting Demodex folliculorum. Methods: Nano-NCL was characterized by particle size, zeta potential, transmission electron microscopy, pH measurement, bacterial culture, and HPLC. Viable Demodex mites were collected from patients’ eyelashes and assigned to six treatment groups: DDW, F127, 0.15% nano-NCL, 0.3% nano-NCL, 20% TTO, and Okra. Mite survival was analyzed using Kaplan–Meier curves. The ocular surface safety was assessed via slit-lamp examination, corneal fluorescein staining, and in vivo confocal microscopy. Results: The nano-NCL particles are uniformly rod-shaped, approximately 291 nm in size, and exhibit good stability, remaining suspended in various media for up to 20 days. The formulation has a stable pH of 6 and demonstrated no bacterial growth, indicating sterility and suitability for clinical use. In vitro, both 0.15% (w/v) and 0.30% (w/v) nano-NCL significantly reduced Demodex survival, with mortality rates ranging from 70.6% to 92.3% within 2 h. Safety evaluations showed minimal corneal staining and inflammation. Notably, 0.15% nano-NCL displayed efficacy comparable to that of 20% tea tree oil (TTO) and Okra, which are established anti-Demodex treatments. Conclusions: Nano-NCL, particularly at 0.15%, rapidly eliminates mites while maintaining excellent ocular tolerability, making it a promising treatment for Demodex-related ocular surface diseases. Full article

Canine demodicosis is a contagious skin disease caused by the over-proliferation of Demodex mites in the host’s hair follicles. This study examines the prevalence, clinical signs, and hematological changes associated with demodicosis in street dogs of Rupandehi, Nepal. Between August 2023 and January 2024, 100 skin scrapings were collected from each street dog presenting dermatological symptoms. The samples, treated with 10% KOH and microscopically examined, revealed a 21% positivity rate for demodicosis, with all cases involving Demodex canis. The infection predominantly affected young puppies (37.5%), females (21.6%), mixed breeds (33.3%), and dogs with above-ideal body conditions (25%). There was no significant association between infection and variables such as age, gender, breed, or nutritional status. Clinically, all affected dogs exhibited alopecia, primarily on the legs. Hematological assessments indicated significant increases in neutrophils and eosinophils and a notable decrease in mean corpuscular hemoglobin concentration and lymphocytes among infected dogs (p < 0.05). This study underscores the importance of vigilant monitoring and comprehensive diagnostic practices in effectively managing and treating canine demodicosis, especially in street dogs. Full article

The presence of Demodex spp. mites on the skin is a common phenomenon in the human population. In most people, it is an asymptomatic infestation, but in some patients, it can contribute to the occurrence of diseases such as demodicosis, rosacea, or blepharitis, as well as non-specific symptoms. In this study, the results of tests assessing the presence of Demodex spp. by direct microscopic examination (DME) in 2508 patients from northern Poland with the suspicion of demodicosis were retrospectively analyzed. A total of 3684 tests were performed. Among them, only 1585 (43.02%) revealed the presence of Demodex spp., while 2099 (56.98%) were negative. It was shown that in the analyzed population of patients with clinical suspicion of demodicosis, the degree of confirmation of the presence of Demodex spp. positively correlated with the patient’s age (p = 0.001) and the mite was mainly found on the edges of eyelids and on the facial skin. Additionally, in men, the presence of Demodex was more often confirmed than in women (p = 0.004). In conclusion, the proper diagnosis of demodicosis still constitutes an important clinical problem due to the non-specificity of symptoms and the low confirmation of clinical suspicions of infestation by DME, especially in lower age groups. Full article

Mites from the Demodecidae and Psorergatidae can optimally use mammalian hosts by inhabiting a number of different microhabitats in their skin. Hence, in individual hosts, several species of parasites from these groups have been described in different microhabitats. There are few data on their co-occurrence either at the host species level or at the host individual level. Most research has addressed the co-occurrence of Demodecidae in carnivorans, ungulates, soricomorphs, and rodents, while the co-occurrence of both families was found in bats. The present study examines the possibility of their co-occurrence in a Eurasian rodent—Apodemus flavicollis. It is a suitable model for such analyses, because representatives of both families have been demonstrated here so far, and our findings extend the list of specific Demodecidae in A. flavicollis with two new species: Demodex tenuis sp. nov. from the lip region and D. mediocris sp. nov. from the chin region. The study also includes the first record of Psorergates muricola in this host, which occurred in the genital–anal region. Therefore, the findings confirm the possibility that different Demodecidae and Psorergatidae species can co-occur in the same host in different body regions. This paper also includes a checklist of Demodecidae and Psorergatidae in rodents around the world. Full article

Zoo conditions are unique for reindeer, since domestic reindeer are not kept in captive facilities like cattle. In the zoo, reindeer are usually surrounded by many different animals that they would never encounter naturally. Thus, they might be infected with new helminths. Numerous petting zoos raise concerns about the safety of tactile interactions for human visitors. Our study is the first large-scale one. Qualitative and quantitative fecal analyses were carried out for 233 reindeer distributed over 50 Russian zoos according to the National Standard of the Russian Federation (GOST R 54627-2011) Ruminant animals—Methods of Laboratory Helminthological Diagnostics. Where possible, DNA analyses of helminths were performed targeting internal transcribed spacer region. As a result, F. hepatica, Paramphistomum sp., Moniezia sp. (including M. expansa), gastrointestinal strongylids (including Nematodirus spp.), Dictyocaulus sp., E. rangiferi, Trichuris sp., and Capillaria sp. were found in 106 (45%) zoo reindeer. All these helminths were previously reported in reindeer and pose no direct danger for humans. The intensity of invasions was mostly low. Fecal examination might be considered as an indirect method for mange diagnostics, as Chorioptes and Demodex mites were found in reindeer fecal samples. The latter may represent a novel species of mite specific for reindeer. Full article

Demodex blepharitis, a chronic lid margin disease, is caused by an infestation of Demodex mites, the most common ectoparasites in human skin and eyelids. Lotilaner ophthalmic solution, 0.25% (Xdemvy, Tarsus Pharmaceuticals), is the first therapy approved to treat Demodex blepharitis. This narrative review characterizes lotilaner ophthalmic solution, 0.25%, and describes its efficacy, safety, and tolerability. The safety and efficacy of lotilaner ophthalmic solution, 0.25%, for treating Demodex blepharitis was evaluated in four phase 2 and two phase 3 trials. The data of 980 patients included in these phase 2 and 3 clinical trials revealed that the proportion of eyes with a clinically meaningful reduction to 10 or fewer collarettes (the cylindrical, waxy debris found at the base of the eyelashes) ranged from 81 to 93%. The mite eradication rate confirmed by a microscopy of epilated lashes ranged from 52 to 78%. No serious treatment-related adverse events were reported in any of these clinical studies. As high as 92% of the patients receiving lotilaner eyedrops in the phase 3 trials found it to be neutral to very comfortable. Given the positive safety and efficacy outcomes, the drug is likely to become the standard of care in the treatment of Demodex blepharitis. Full article