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.

Performance of CO1 and ITS2 nested PCR in molecular identification of ordinary scabies (Sarcoptes scabiei var. hominis)

Scabies is a global disease with a high prevalence, causing morbidity and even mortality, especially in poor and developing countries. However, it is often misdiagnosed due to varied and unspecified lesions. The gold standard technique for diagnosis is a microscopic examination, which requires experienced experts in finding mites, mainly in ordinary scabies. CO1 and ITS2 genes have been widely used in molecular identification to detect Sarcoptes scabiei and its variants. This study aimed to determine and compare the sensitivity and specificity of CO1 and ITS2 S. scabiei genes to the microscopic examination of scabies skin scrapings. The skin scrapings of 52 subjects with scabies diagnosed by anamnesis, physical examination, and dermoscopic examination were examined under a microscope and analyzed by nested PCR. The diagnostic test result showed that the sensitivity of nested PCR of both CO1 and ITS2 genes to micro‐ scope examination was 100%. However, the specificity of both CO1 and ITS2 nested PCR was poor (24% and 0%). Hence, CO1 and ITS2 nested PCR could be more suitable for screening ordinary scabies in humans than the microscopic examination.

Quality of life in patients with scabies in Erbil, Iraq

Background and objective: Scabies, known as the seven-year itch, is a contagious skin infestation by the mite Sarcoptes scabiei that causes a pruritic skin eruption. Scabies is endemic in most of the communities of the developing world. This study aimed to assess the quality of life of scabies patients, taking into consideration the demographic profile and clinical presentation of patients in Erbil. Methods: In this cross-sectional study, 107 scabies patients attending a private dermatology clinic were recruited. Dermatology Quality of Life Index questionnaire was used for data collection. Results: More than half (51.4%) of the patients were less than 30 years of age, including 58.9% males, 70.1% of them were married, and 67.3% were living in the urban area. More than 84% of the study sample’s quality of life was very large and extremely large affected. The overall mean of the quality of life scores was 14.95±4.5 with no significant association between the overall quality of life scores to disease severity and certain sociodemographic characteristics of the patients. The mean scores of the two domains of embarrassment and shopping were significantly associated with the male gender (P = 0.003 and 0.021, respectively). However, 40.2%, 35.5%, and 29% of the patients reported that the disease affected very much on their shopping, clothing, and working activities, respectively. Conclusion: The disease had caused a significant effect on patients' lives, with no significant association between the severity of the disease and overall quality of life scores. The disease in its mild, moderate, and severe forms adversely affected patient lives. The commonest quality of life scores were those in the range of 11-20. Keywords: Quality of life; Scabies; Erbil; Iraq.

THE EFFICACY OF INVERMECTION IN TREATMENT OF SARCOPTIC MANGE IN GOATS

The efficacy of invermection in treatment of an outbreak of mange Moritanin and local adults caused by Sarcoptes Scabiei Var Carprae mites was studied Invermection was given S/C at a dose rate 0.2 mg/kg. body weight twice at an interval of 14 days for 20 infested Moritanin adults and 20 local adults goats. Invermection was 100% effective, and all goats were in good condition after treatment.

Penanganan scabies pada kucing mix-persia di Rafa Pet’s Care

Scabies merupakan penyakit kulit pada ternak maupun hewan kesayangan yang disebabkan oleh tungau Sarcoptes scabiei atau Notoedres cati pada lapisan korneum kulit. Pemilik mengeluhkan kucing jantan mix-persia bernama Simba keluar rumah selama beberapa hari, kemudian pulang dalam kondisi ada luka diwajah, sering terlihat gelisah dan menggaruk bagian wajah, sedangkan makan dan minum kucing normal. Pemeriksaan fisik tampak rambut kusam, alopesia, terdapat lesi dibagian kepala, terdapat hiperkeratosis dibagian kepala dan telinga bagian luar. Pemeriksaan sitologi dilakukan dengan teknik superfisial skin scraping dan terlihat tungau Notoedres cati. Diagnosa kucing tersebut terkena penyakit scabies/scabiosis. Terapi yang diberikan adalah wormectin® (avermectin) dosis 0,05 ml/kg bobot badan injeksi tunggal. Hari ke 9 pasca-terapi menunjukkan pemulihan berupa keropeng mulai hilang, lesi akibat garukan kucing mulai mengering dan beberapa bagian rambut yang rontok mulai tumbuh kembali.

Identification of Sarcoptes scabiei by Clinical Examination and Follow-up Examination in Medan City, Indonesia

Background: Scabies is a disease caused by the mite Sarcoptes scabiei var. hominis. In Indonesia, scabies ranks third out of the 12 most common skin diseases. In terms of disease screening, direct visualization of dermatitis from mites and microscopy of skin scrapings is less sensitive. PCR and dermoscopy examinations have a high sensitivity value to Sarcoptes mites. Aims: This study aims to identify Sarcoptes scabiei mites between clinical symptoms and supporting examinations, namely PCR and dermoscopy methods. Methods: This research is a cross-sectional study, with descriptive analytics. The number of samples of 50 people who met the inclusion criteria was examined by microscopic examination, dermoscopy, and PCR. We state it to be positive if we found scabies mites or their eggs on microscopy, delta wing sign, or jet wet contrail on dermoscopy and there is a 135bp DNA band on PCR. Results: 50 samples diagnosed with scabies based on cardinal sign of scabies, gender were 80% male and 20% female with an average age of 14 years. Based on the location of the rash, the most rashes were between the fingers and toes, each 26% and the least on the head as much as 2%. Based examination tools, no Sarcoptes scabiei mites were found through microscopic and dermoscopic examination, while the PCR examination found 12 positive samples of scabies. Conclusion: PCR examination is very sensitive and specific even in very small quantities, with the fore primer SSUDF and the reverse primer SSUDR. Further research is needed to assess the sensitivity and specificity of dermoscopy and PCR in diagnosing scabies.

Transcriptome Analysis of Host Inflammatory Responses to the Ectoparasitic Mite Sarcoptes scabiei var. hominis

Scabies, a human skin infestation caused by the ectoparasitic mite Sarcoptes scabiei var. hominis, affects more than 200 million people globally. The prevailing knowledge of the disease process and host immune response mechanisms is limited. A better understanding of the host-parasite relationship is essential for the identification of novel vaccine and drug targets. Here we aimed to interrogate the transcriptomic profiles of mite-infested human skin biopsies with clinical manifestations of ordinary scabies subjects (“OS”; n = 05) and subjects naive to scabies (“control”; n = 03) using RNASeq data analysis. A combined clustering, network, and pathway mapping approach enabled us to identify key signaling events in the host immune and pro-inflammatory responses to S. scabiei infestation. The clustering patterns showed various differentially expressed genes including inflammatory responses and innate immunity genes (DEFB4A, IL-19, CXCL8, CSF3, SERPINB4, S100A7A, HRNR) and notably upregulation of the JAK-STAT pathway in scabies-infested samples. Mite-infested human skin biopsies (GSE178563) were compared with an ex-vivo porcine infested model (E-MTAB-6433) and human skin equivalents (GSE48459). Marked enrichment of immune response pathways (JAK-STAT signaling, IL-4 and IL-13 pathway, and Toll receptor cascade), chemokine ligands and receptors (CCL17, CCL18, CCL3L1, CCL3L3, CCR7), and cytokines (IL-13 and IL-20) were observed. Additionally, genes known for their role in psoriasis and atopic dermatitis were upregulated, e.g., IL-19. The detailed transcriptomic profile has provided an insight into molecular functions, biological processes, and immunological responses and increased our understanding about transcriptomic regulation of scabies in human.

Activity of terpenes derived from essential oils against Sarcoptes scabiei eggs

Background The limited ovicidal activity of currently available acaricides is a significant obstacle to efficacious scabies treatment. Several essential oils or their respective components have proved to be active against the eggs of arthropods, mainly lice and ticks. Information on the activity of these oils and/or components against the eggs of mites remains very limited. The aim of this study was to assess the activity of six terpenes (carvacrol, eugenol, geraniol, citral, terpinen-4-ol and linalool) commonly found in essential oils against the eggs of Sarcoptes scabiei. Methods Sarcoptes eggs were exposed to paraffin oil containing 1, 2.5, or 5% of each terpene tested. After a 12-h exposure period, the eggs were washed and placed in paraffin oil for hatching. Embryonic development following treatment was assessed every day to determine the stage of developmental arrest. Results The median effective concentration to obtain 50% egg mortality (EC50) was 0.5, 0.9, 2.0, 4.8, 5.1 and 9.8% for carvacrol, eugenol, geraniol, citral, terpinen-4-ol and linalool, respectively. The microscopic images of eggs after each treatment indicated that these six terpenes may act by penetrating through the aeropyles on the egg surface. Conclusions In conclusion, carvacrol, eugenol and geraniol possess significant ovicidal activities, which should be considered as promising ovicidal agents for the treatment of scabies. Graphical Abstract