Molecular characterization of Sarcoptes scabiei causing severe mange in two Andean foxes (Lycalopex culpaeus) from Peru.

Cases of sarcoptic mange in the wildlife population have been increasing around the world in recent years. In this study, we report the first case of severe sarcoptic mange in two Andean foxes (Lycalopex culpaeus) and molecularly analyze the collected mites. The National Forestry and Wildlife Service of Lima, Peru, found an adult male Andean fox in the province of Callao in August 2022. The veterinarians decided to euthanize the fox due to the severity of the mange. In August 2023, an adult male Andean fox was found dead in the province of Huaral by veterinarians. Both foxes were sent to the veterinary school in Lima for necropsy. Skin samples from different body zones were digested in buffer lysis, and mites were detected in the tissue samples. A morphological diagnosis identified the mites as Sarcoptes scabiei. The mites from both foxes had the same nuclear (ITS2) and mitochondrial (cox1) genetic marker sequences as the S. scabiei sequences from dogs, vicunas, Andean foxes, and water buffalos recorded in GenBank. Unlike ITS2, phylogenetic analysis of S. scabiei cox1 showed host-related nucleotide sequence polymorphisms. Future molecular studies of S. scabiei from different hosts and localities will be necessary to better understand the transmission of this disease in Andean foxes.

Standardized cotton swab sampling with nested quantitative polymerase chain reaction is effective for diagnosing ordinary scabies.

BACKGROUND: Low sensitivity of the PCR assay for diagnosing scabies has been noted because of the difficulty in obtaining tissue containing Sarcoptes scabiei DNA. AIM: To evaluate nested real-time quantitative PCR (nRT-qPCR) with nonexpert-dependent standardized cotton swab sampling (CSW) as a tool for diagnosing scabies. METHODS: All patients underwent dermoscopic and microscopic examination (MS) with scraped sampling (Sc). Patient samples were acquired with a single, dry swab rubbed across the flexor areas of both wrists as well as the eight interdigital spaces and on any suspected scabies lesions. nRT-qPCRs were performed with Sc and CSW samples. RESULTS: Out of 125 patients with suspected scabies, 120 patients were sampled, and 57 were positive (positive with: MS n = 53; nRT-qPCR with Sc n = 52; nRT-qPCR with CSW n = 46) and 63 were negative for scabies. The sensitivities of these tests were 93.0%, 91.2% and 80.7%, respectively, which were not different statistically (P > 0.05). However, upon subsequent monitoring after treatment, the sensitivity of nRT-qPCR with CSW was only 36.6%, which was significantly lower than 83.0% for MS and 92.7% for nRT-qPCR with Sc (P < 0.001). The obtained sequences showed 97%-100% homology with scabies sequences deposited in GenBank. CONCLUSION: CSW with nRT-qPCR shows sensitivity close to MS with scraping performed by experts for diagnosing scabies in an outpatient setting, but not for post-treatment monitoring. CSW with nRT-qPCR may be useful for physicians unfamiliar with a traditional diagnostic method, and for screening an outbreak in community facilities.

Detection of a knockdown mutation in the voltage-sensitive sodium channel associated with permethrin tolerance in Sarcoptes scabiei var. hominis mites.

BACKGROUND: Increasing evidence has sparked a debate on the loss of sensitivity of scabies mites to conventional permethrin therapy. Mutations in the voltage-sensitive sodium channels (VSSC) were associated with knockdown resistance (kdr) in many arthropods, but have never been identified in Sarcoptes scabiei variatio (var.) hominis mites. OBJECTIVES: To identify factors contributing to therapy failure. METHODS: Sixty-seven mites were collected from 64 scabies-infested patients in Vienna, Austria, of whom 85.9% were refractory to prior permethrin-based treatments, and genotyped for the presence of nucleotide polymorphisms in Domain II of the VSSC, known to be associated with kdr. Information regarding previous antiscabietic therapies, decontamination procedures and possible re-infestations by contacts as well as the response to re-imposed therapies were obtained. RESULTS: Sequence alignment comparisons revealed previously unidentified mutations in the coding region of Domain II of the VSSC. A novel A1663T transversion was detected in 97.0% of the mites, resulting in a non-synonymous substitution from methionine to leucine, M918L, a mutation known to confer kdr in other arthropods. In addition, a synonymous G1659A transition was identified in one mite, which otherwise showed a nucleotide sequence identical to the wild-type reference. No major inconsistencies were observed within the previous therapeutic and decontamination procedures, which could have accounted for the observed non-responsiveness to permethrin-based therapies. Subsequent cure of infestation was achieved in 65.6% of the participants, predominantly by combination therapies with topical permethrin and systemic ivermectin. However, in 14.6% of the cured cases, permethrin monotherapy sufficed for eradication of scabies, albeit in some cases prolonged exposure was necessary. CONCLUSIONS: The kdr-associated M918L mutation in the VSSC gene has now emerged in S. scabiei var. hominis mites. Hence, loss of sensitivity to permethrin due to kdr-type resistance may be more prevalent than anticipated and may be decisive for the therapy responsiveness of scabies-infested patients.

Sarcoptes scabiei infestation in a captive lowland tapir (Tapirus terrestris): case report, morphological and molecular genetic mite identification.

Sarcoptes scabiei (Acari: Sarcoptidae) is a globally distributed parasitic mite species, which causes mange in a broad spectrum of domestic and wild mammals. In the present study, we report a case of chronic S. scabiei infestation in a captive lowland tapir (Tapirus terrestris) held in a multi-species exhibit at Vienna Zoo. The adult male showed clinically manifested mange flare-ups three times at an interval of up to 12 months, diagnosed by positive deep-skin scrapings and successfully treated by oral applications of ivermectin (0.1-0.2 mg/kg body weight) and washings with antimicrobial solutions. Clinical symptoms including pruritus, alopecia, erythema, crusts, and superficial bleedings were limited to the axillar and pectoral region, as well as distal limbs. The affected tapir died from underlying bacterial pneumonia during general anesthesia. Skin scrapings, necropsy, and histopathological analysis of mite material (eggs, larvae, and adults) permitted further morphological and molecular identification. The morphological features described here matched the characteristics for the species S. scabiei and molecular data verified morphological identification. Cross-species transmission plays a key role in the expansion of this neglected emerging panzootic disease and urban wildlife could potentially bridge the gap between free-ranging wildlife reservoirs and zoo animals. However, further examinations are needed to detect the primary source of infestation and discover transmission pathways within the zoo.

Permethrin Steal Effect by Unmasked Corneocytic Keratin in Topical Therapy of Scabies.

INTRODUCTION: The use of epicutaneously applied permethrin in the treatment of common scabies is considered to be the first-line therapy. Due to increasing clinical treatment failure, the development of genetic resistance to permethrin in Sarcoptes scabiei var. hominis has been postulated. In addition, metabolic resistance and pharmacokinetic limitations by parasitic digestion and reactive thickening of stratum corneum are suspected to cause a reduction in cutaneous bioavailability. METHODS: Since lipophilic permethrin is known to form hydrophobic interactions with proteins via van der Waals interactions, a similar interaction was assumed and investigated for permethrin and the protein keratin. Using keratin particles extracted from animal material, a model for hyperkeratotic and parasitic digested scabies skin was developed. Using fluorescence-labeled keratin and ³H-permethrin, their interaction potential was validated by loading and unloading experiments. Additionally, the impact of keratin to permethrin penetration was investigated based on an in vitro model using Franz diffusion cells. RESULTS: For the first time, keratin particles were introduced as a model for dyskeratotic skin, as we were able to show, the keratin particles' interaction potential with permethrin but no penetration behavior into the stratum corneum. Moreover, comparative penetration experiments of a reference formulation with and without added keratin or keratin-adherent permethrin showed that keratin causes a steal effect for permethrin, leading to a relevant reduction in cutaneous bioavailability in the target compartment. CONCLUSION: The results provide further evidence for a relevant pharmacokinetic influencing factor in the epicutaneous application of permethrin and a rationale for the necessity of keratolytic pretreatment in hyperkeratotic skin for the effective use of topical permethrin application in scabies.

Artificial Infestation of Sarcoptes scabiei (Acari: Sarcoptidae) in Rabbits Exhibits Progressive Pathological Changes, Apoptosis, and Keratinization in the Skin.

Sarcoptes scabiei (S. scabiei) is an ectoparasite that can infest humans and 150 mammalian host species, primarily causing pruritus, crust, and alopecia. However, neither the pathological process of host skin under S. scabiei infection nor the mechanism of S. scabiei infection in regulating apoptosis and keratinization of host skin has been studied yet. In this study, a total of 56 rabbits were artificially infested with S. scabiei, and the skin samples were collected at seven different time points, including 6 h, 12 h, day 1, day 3, 1 week, 4 weeks, and 8 weeks, whereas a group of eight rabbits served as controls. We measured epidermal thickness by H&E staining, observed the skin ultrastructure by electron microscopy, and detected the degree of skin apoptosis by TUNEL staining. The level of transcription of genes related to apoptosis and keratinization was detected by quantitative real-time PCR (qRT-PCR), and the level of Bcl-2 protein expression was further detected using immunohistochemistry. Our results showed that, with increased infestation time, the epidermal layer of the rabbit skin exhibited significant thickening and keratinization, swollen mitochondria in the epidermal cells, and increased skin apoptosis. The level of caspase-1, 3, 8, 10, 14, and Bcl-2 mRNA expression was increased, whereas the level of keratin 1 and 5 was decreased after S. scabiei infestation. In conclusion, S. scabiei infestation causes thickening of the epidermis, which may be related to apoptosis-induced proliferation and skin keratinization.

Scabies in a 14-year-old girl with superficial epidermolytic ichthyosis.

A 14-year-old girl who reported generalized scaling and hyperkeratosis since age 1 year presented with severe pruritus of several months' duration. Scabies mites were detected, and molecular genetic analysis subsequently revealed a rare pathogenic variant in the keratin 2 (KRT2) gene, confirming a diagnosis of superficial epidermolytic ichthyosis. Treatment with oral ivermectin led to complete remission of symptoms. Disorders of keratinization can mimic clinical signs of scabies, leading to a delay in diagnosis.

Occurrence of sarcoptic mange in free-ranging vicuñas (Vicugna vicugna) of the Andean high plateau region of Argentina.

Free-ranging vicuñas (Vicugna vicugna) are handled in some areas of the Andean high plateau region following an ancestral practice known as chaku, which consists in their transient capture and shearing of their fiber for commercialization. In this study, 807 vicuñas captured during 12 chaku events that took place in 2019 in the province of Jujuy, Argentina, were examined for typical mange skin lesions. Twenty-eight of the examined vicuñas presented alopecia with erythema, exudation, hyperkeratosis, and/or bleeding scarred lesions, mostly in the chest, rear and front legs, and inguinal zone. Most of the cases (82%) appeared in Laguna Cucho at 4900 masl, where 23% of the animals presented these skin reactions. Microscopic evaluation of skin scrapings revealed the presence of a great number of 0.1- to 0.4-mm-long mites of different life cycle stages, morphologically compatible with the species Sarcoptes scabiei. This etiological agent was confirmed by PCR amplification and sequencing of a cox-1 species-specific segment. Histopathological examination of skin biopsies showed extensive infiltration of the dermis with lymphocytes, neutrophils and eosinophils, hyperplasia at different stages, epidermis degeneration, and hyperkeratosis. This is the first characterization of sarcoptic mange in free-ranging vicuñas by clinical examination, mite morphology, histopathological studies, and molecular confirmation in the region. Mange hampers the welfare of vicuñas and the economy of the local communities that organize chaku events since infested vicuñas cannot be sheared. Its long-term effects are unknown but it might affect the fitness and survival of this iconic South American camelid.

The genetic characteristics of Sarcoptes scabiei from Chinese serow (Capricornis milneedwardsii) and goral (Naemorhedus goral arnouxianus) compared with other mites from different hosts and geographic locations using ITS2 and cox1 sequences.

Scabies is a common parasitic disease in many mammalian species, caused by the infestation of Sarcoptes scabiei. There is no consistent conclusion on whether Sarcoptes mites from different hosts or geographic locations have apparent genetic divergence. In this study, we collected and morphologically identified S. scabiei from Chinese serow and goral, and we described the genetic diversity of S. scabiei and other mites based on phylogenetic analyses of the ITS2 and cox1 sequence fragments, including data available in GenBank. The mites isolated from Chinese serow and goral were S. scabiei, and they were morphologically similar. The phylogenetic trees and haplotype networks showed that S. scabiei from other locations worldwide did not cluster according to host divergence or geographical distribution. Additionally, the Fst values were - 0.224 to 0.136 and - 0.045 to 1 between S. scabiei from different hosts, including humans and domestic and wild animals, based on partial ITS and cox1 sequences. Worldwide S. scabiei samples formed three clusters (with H2, H5, and H12 at their centers) in the ITS and one cluster (with C9 at the center) in the cox1 haplotype phylogenetic network. The S. scabiei collected from Chinese serow and goral were morphologically similar and had the same genotype. A study on the genetic characteristics of S. scabiei from Chinese serow and goral together with other mites from different hosts and geographic locations around the world showed no obvious divergence. These findings indicated that scabies likely is a zoonotic disease and that the global prevalence of scabies is probably related to the worldwide trade of domestic animals.

Effects of Sarcoptes scabiei Translationally Controlled Tumor Protein (TCTP) on Histamine Release and Degranulation of KU812 Cells.

Scabies is a common parasitic dermatological infection worldwide that is often neglected. Scabies mites stimulate host inflammatory symptoms via secreted and excreted proteins, which induce basophil and mast cell degranulation and host histamine release. However, the mechanism of degranulation and histamine release is unclear. Moreover, the Sarcoptes scabiei translationally controlled tumor protein (TCTP) is predicted as an excreted protein, which may be involved in host inflammatory response regulation. First, we evaluated S. scabiei TCTP gene (SsTCTP) transcription in larvae, nymphs, and adults by qRT-PCR, and SsTCTP transcription was highest in larvae, followed by nymphs. Second, we found that the S. scabiei TCTP recombinant protein (rSsTCTP) promoted mice histamine release in vivo by Evans blue Miles assay. Therefore, to further explore the possible role of S. scabiei TCTP in host inflammatory response regulation, we established a degranulation model of KU812 cells. The results of the degranulation model suggested that rSsTCTP could induce enhanced degranulation of KU812 cells and increase the secretion of histamine and the expression of IL-4, IL-6, and IL-13 in vitro. In conclusion, we speculate that scabies mites could stimulate host histamine release and Th2 response by excreting S. scabiei TCTP.

Evidence that Transcriptional Alterations in Sarcoptes scabiei Are under Tight Post-Transcriptional (microRNA) Control.

Here, we explored transcriptomic differences among early egg (Ee), late egg (Le) and adult female (Af) stages of the scabies mite, Sarcoptes scabiei, using an integrative bioinformatic approach. We recorded a high, negative correlation between miRNAs and genes with decreased mRNA transcription between the developmental stages, indicating substantial post-transcriptional repression; we also showed a positive correlation between miRNAs and genes with increased mRNA transcription, suggesting indirect post-transcriptional regulation. The alterations in mRNA transcription between the egg and adult female stages of S. scabiei were inferred to be linked to metabolism (including carbohydrate and lipid degradation, amino acid and energy metabolism), environmental information processing (e.g., signal transduction and signalling molecules), genetic information processing (e.g., transcription and translation) and/or organismal systems. Taken together, these results provide insight into the transcription of this socioeconomically important parasitic mite, with a particular focus on the egg stage. This work encourages further, detailed laboratory studies of miRNA regulation across all developmental stages of S. scabiei and might assist in discovering new intervention targets in the egg stage of S. scabiei.

An RNA Interference Tool to Silence Genes in Sarcoptes scabiei Eggs.

In a quest for new interventions against scabies-a highly significant skin disease of mammals, caused by a parasitic mite Sarcoptes scabiei-we are focusing on finding new intervention targets. RNA interference (RNAi) could be an efficient functional genomics approach to identify such targets. The RNAi pathway is present in S. scabiei and operational in the female adult mite, but other developmental stages have not been assessed. Identifying potential intervention targets in the egg stage is particularly important because current treatments do not kill this latter stage. Here, we established an RNAi tool to silence single-copy genes in S. scabiei eggs. Using sodium hypochlorite pre-treatment, we succeeded in rendering the eggshell permeable to dsRNA without affecting larval hatching. We optimised the treatment of eggs with gene-specific dsRNAs to three single-copy target genes (designated Ss-Cof, Ss-Ddp, and Ss-Nan) which significantly and repeatedly suppressed transcription by ~66.6%, 74.3%, and 84.1%, respectively. Although no phenotypic alterations were detected in dsRNA-treated eggs for Ss-Cof and Ss-Nan, the silencing of Ss-Ddp resulted in a 38% reduction of larval hatching. This RNAi method is expected to provide a useful tool for larger-scale functional genomic investigations for the identification of essential genes as potential drug targets.

Scabies polymerase chain reaction with standardized dry swab sampling: an easy tool for cluster diagnosis of human scabies.

BACKGROUND: Expert visualization of Sarcoptes scabiei remains essential for diagnosing human scabies, but access to said experts can be difficult. Polymerase chain reaction (PCR) is a specific tool for the detection and confirmation of S. scabiei but has poor sensitivity. OBJECTIVES: To evaluate PCR as a diagnostic method for scabies using nonexpert-dependent standardized sampling. METHODS: The dry swab was systematically rubbed across the front of both wrists, the eight interdigital spaces and on any suspected scabies lesions in all patients referred for scabies. A new PCR-based diagnostic test was run on the samples. All patients underwent clinical and dermoscopic examination. Scabies diagnosis was confirmed when dermoscopic examination was positive or the patient had typical clinical signs of scabies. RESULTS: Of 183 suspected cases of scabies, 164 patients were sampled, 87 had confirmed scabies (dermoscopy positive n = 87, typical clinical signs n = 1) and 77 did not. Of the 87 patients with proved scabies, 33 patients had positive scabies PCR, resulting in a 37·9% [95% confidence interval (CI) 28·4-48·4%] sensitivity and a 61·7% (95% CI 52·4-72·7%) negative predictive value. None of the 77 patients ruled out for scabies had a positive PCR result. CONCLUSIONS: This method is nontraumatic, repeatable and non-expert-dependent. It shows sensitivity similar to previous studies involving expert skin scraping. However, this method facilitates the multiplication of sampling, which increased the sensitivity for cluster scabies diagnosis. This method may be suitable as a first-line diagnosis tool where a large cluster scabies outbreak is suspected. What's already known about this topic? Scabies diagnosis requires expertise. Scabies polymerase chain reaction (PCR) is specific but has poor sensitivity. Poor sensitivity is the consequence of the low efficiency of sampling methods. What does this study add? This PCR-based diagnostic method based on nontraumatic standardized skin sampling is not expert-dependent and is reproducible. This diagnostic method may be relevant as a non-expert sentinel diagnosis tool in large clusters where a scabies outbreak is suspected.

Prevalence and associated factors of scabies in Ethiopia: systematic review and Meta-analysis.

BACKGROUND: Scabies is an infectious disease that affects the skin caused by the mite Sarcoptes scabiei and it transmitted through close personal contact. Even though it is easily treatable disease, its prevalence is high and continuous as neglected tropical disease of resource-poor settings, and particularly affects young age groups. Despite of these facts, studies conducted in Ethiopia regarding to the prevalence and associated factors for scabies infestation have been highly variable and didn't well compiled. Due to that, the aim of this systematic review and meta-analysis was to estimates the overall prevalence of scabies and associated factors in all age groups in Ethiopia. METHODS: International databases (PubMed/PMC/Midline, EMBASE, CINAHL, Web of Science, Google Scholar, Google and Science Direct) were systematically searched from December 1, 2019, to January 18, 2020. All observational studies noted the prevalence of human scabies and associated factors in Ethiopia were included. Two authors (AG and G.T) independently extracted all necessary data using a standardized data extraction format. The data which is extracted each study were analyzed using STATA Version 14.1. Heterogeneity among the included studies was assessed through the Cochrane Q test statistics and I2 test. Lastly, a random effects meta-analysis model was computed to fix overall prevalence and associated factors of scabies. RESULTS: Twelve studies were included in this meta-analysis after 410 articles retrieved. Of these, eight studies were analyzed for prevalence estimation. The overall prevalence of scabies infestation was 14.5% (95%CI: 1.5, 27.6%) in Ethiopia. Furthermore, the subgroup analysis revealed the highest prevalence was 19.6% in Amhara region. A person from a large family size (OR: 3.1, 95% CI: 1.76, 5.67), and sharing a bed (OR: 3.59, 95%CI: 2.88, 4.47) were significantly associated with scabies. CONCLUSION: This study revealed the prevalence of scabies infestation was 14.5% in Ethiopia which was high. Persons from high family size and any contact with scabies case were factors associated with scabies.

The complete mitochondrial genome of Sarcoptes scabiei var. nyctereutis from the Japanese raccoon dog: Prediction and detection of two transfer RNAs (tRNA-A and tRNA-Y).

Sarcoptes scabiei (Acari: Sarcoptidae) causes a common contagious skin disease that affects many mammals. Here, the complete mitochondrial genome of a mite, S. scabiei var. nyctereutis, from Japanese wild raccoon dogs was analyzed. The 13,837bp circular genome contained 13 protein-coding genes, two rRNA genes, and 22 tRNA genes. For the first time, two tRNAs (alanine and tyrosine), that were thought to be absent in scabies mites from other animals, were predicted to have short, non-cloverleaf structures by in silico annotation and detected by RT-PCR, sequencing, and northern analysis. The mitochondrial genome structure of S. scabiei is similar to that of Psoroptes cuniculi and Dermatophagoides farinae. While small and unusual tRNA genes seem to be common among acariform mites, further experimental evidence for their presence is needed. Furthermore, through an analysis of the cox1 gene, we have provided new evidence to confirm the transmission of this mite between different animal hosts.

Sarcoptic Mange of Fox Origin in Multiple Farm Animals and Scabies in Humans, Switzerland, 2018.

Fox-derived Sarcoptes scabiei mites caused an outbreak of mange on a farm in Switzerland in 2018. Pruritic skin lesions suggestive of S. scabiei mite infestation developed in 4 humans who had direct contact with affected farm animals but not foxes. Sarcoptic mange is continuously spreading; such outbreaks affecting humans could start occurring more frequently.

The efficacy of a nested polymerase chain reaction in detecting the cytochrome c oxidase subunit 1 gene of Sarcoptes scabiei var. hominis for diagnosing scabies.

BACKGROUND: A widespread scabies infestation, associated with long-term residence in nursing homes, is becoming an issue in high-income countries. Mineral oil examination is regarded as the gold standard in diagnosing scabies, but the sensitivity of this method is generally low - approximately 50%. Molecular techniques may contribute to enhancing the sensitivity of current tests for laboratory diagnosis of human scabies. OBJECTIVES: To develop new primers for a nested polymerase chain reaction (PCR) for the cytochrome c oxidase subunit 1 (cox1) gene of Sarcoptes scabiei var. hominis to increase the sensitivity of a previously developed conventional PCR. METHODS: Patients with clinically suspected scabies underwent dermoscopy-guided skin scraping with microscopic examination. The diagnosis was positive for scabies when mites or eggs were found under the microscope, and patients were then designated as 'microscopy positive'. Patients who presented with negative microscopic results were placed in the 'microscopy-negative' group. Skin scrapings were collected from both groups for PCR. RESULTS: Of the total 63 samples, 28 were microscopy positive and 35 were negative with no differences in sex and age between the two groups. All microscopically proven cases of scabies were positive using the cox1 nested PCR. Among microscopy-negative samples, S. scabieiDNA was detected in nine. If sensitivity of the cox1 nested PCR is considered 100% [95% confidence interval (CI) 90·5-100], then sensitivity of microscopy is 75·7% (95% CI 58·8-88·2; P = 0·004). CONCLUSIONS: Nested PCR can be successfully used as an alternative method for diagnosing suspected scabies. Therefore, infection control measures and treatments can be initiated before significant transmission occurs, minimizing the risk of outbreaks.

Identification of a novel PYP-1 gene in Sarcoptes scabiei and its potential as a serodiagnostic candidate by indirect-ELISA.

Scabies is a parasitic disease caused by the ectoparasite Sarcoptes scabiei, affecting different mammalian species, including rabbits, worldwide. In the present study, we cloned and expressed a novel inorganic pyrophosphatase, Ssc-PYP-1, from S. scabiei var. cuniculi. Immunofluorescence staining showed that native Ssc-PYP-1 was localized in the tegument around the mouthparts and the entire legs, as well as in the cuticle of the mites. Interestingly, obvious staining was also observed on the fecal pellets of mites and in the integument of the mites. Based on its good immunoreactivity, an indirect enzyme-linked immunosorbent assay (ELISA) using recombinant Ssc-PYP-1 (rSsc-PYP-1) as the capture antigen was developed to diagnose sarcoptic mange in naturally infected rabbits; the assay had a sensitivity of 92·0% and specificity of 93·6%. Finally, using the rSsc-PYP-1-ELISA, the Ssc-PYP-1 antibody from 10 experimentally infected rabbits could be detected from 1 week post-infection. This is the first report of S. scabiei inorganic pyrophosphatase and the protein could serve as a potential serodiagnostic candidate for sarcoptic mange in rabbits.

Sarcoptes scabiei on hedgehogs in New Zealand.

European hedgehogs (Erinaceus europaeus) were introduced into New Zealand from Britain during the period from 1869 to the early 1900s. The only mite found on New Zealand hedgehogs in early studies was Caparinia tripilis, with Sarcoptes scabiei first being reported in 1996. The aim of this study was to investigate the prevalence of Sarcoptes infestation on hedgehogs in New Zealand, the number of mites found and the degree of mange observed. Dead hedgehogs were collected from veterinary clinics, rescue centres, members of the public and from road-kill. Twenty-one (55.3%) of the animals examined had visible skin lesions. Both Caparinia and Sarcoptes mites were identified on microscopic examination with Sarcoptes the most common, being found on over 70% of animals examined (n = 38). The numbers of mites recovered after brushing the head and body ranged from 1 to 5659 (median = 341 mites) with only six animals (22.2%) having fewer than 10 Sarcoptes mites found. Caparinia mites were seen on fewer animals and generally in very low numbers. These findings indicate a change in the mite populations on hedgehogs in New Zealand and that infected animals develop the debilitating hyperkeratotic form of sarcoptic mange without an accompanying hypersensitivity response limiting numbers of mites. Analysis of the cox 1 gene of Sarcoptes from two hedgehogs showed close alignment to sequences derived from a pig with one and from a dog with the second. More work needs to be undertaken to identify the source(s) of the Sarcoptes found on hedgehogs in New Zealand and whether other mammalian hosts may be infected from contact with hedgehogs.

Genetic variability of wildlife-derived Sarcoptes scabiei determined by the ribosomal ITS-2 and mitochondrial 16S genes.

Infestation by the ectoparasitic mite Sarcoptes scabiei (Acari: Sarcoptidae) has important implications for global wildlife conservation and both animal and human health. Ribosomal and mitochondrial DNA sequences of parasites are useful to determine genetic diversity and to describe their likely dynamic evolution. In this study, we described the genetic diversity of S. scabiei individuals collected from wild animals in China by sequencing the ribosomal ITS-2 and mitochondrial 16S rRNA genes. A total of 13 Sarcoptes isolates of wildlife, coupled with one of rabbit origin, were subjected to genetic characteristics. After cloning and sequencing, 14 ITS-2 sequences and 12 16S rRNA sequences were obtained and analyzed. Further analysis of haplotype network and population genetic structure revealed that there were 79 haplotypes in ITS-2 (main haplotype H2) and 31 haplotypes in 16S rRNA (main haplotype C10). The phylogenetic trees showed some partial clustering by location and host, and the analysis of gene polymorphism may prompt that all isolates of S. scabiei have a similar origin. We speculate that the genetic evolution of S. scabiei may be related with that of the hosts, but more research is necessary to better understand the host-parasite co-evolutionary relationship in S. scabiei. These results provide new insights into understanding the population genetics and evolutionary biology of S. scabiei and therefore a better understanding of controlling its infestation pathways worldwide.