Topic
Sarcoptidae
About: Sarcoptidae is a research topic. Over the lifetime, 122 publications have been published within this topic receiving 2880 citations.
Papers published on a yearly basis
Papers
TL;DR: A simple in-vitro analysis used to evaluate the relative efficacy of a range of topical, oral, and herbal treatments available in Australia for the treatment of scabies found no evidence of any mite tolerance in vivo or treatment failure in any patients or contact cases.
Abstract: Resistance of Sarcoptes scabiei to various topical therapies has been described, but clinical assessment of treatment failure is problematic and in-vitro assays are generally not available. We describe a simple in-vitro analysis used to evaluate the relative efficacy of a range of topical, oral, and herbal treatments available in Australia for the treatment of scabies. S. scabiei var. hominis mites were collected from skin scrapings obtained from 7 crusted scabies patients over a period of 2 years (1997 and 1998). Larvae, nymphal instars, and adult mites were tested within 3 h of collection and continuously exposed to selected commercially available treatment products until death, with the elapsed time recorded. Neem was the only product to show little acaricidal activity. Survival curves indicated that, of the other agents, 5% permethrin (Lyclear) had the slowest killing time, with 35% of mites still alive after 3 h, and 4% still alive after 18-22 h of constant exposure. In contrast, no mites were alive after 3 h exposure to 25% benzyl benzoate (Ascabiol), 1% lindane (Quellada), 5% tea tree oil and 100-8000 ng/g of ivermectin (Equimec). Despite the slower killing time with 5% permethrin, there was no evidence of any mite tolerance in vivo or treatment failure in any patients or contact cases.
172 citations
TL;DR: Previous data that gene flow between scabies mite populations on human and dog hosts is extremely rare in northern Australia clearly support the previous contention that control programs for human scabies in endemic areas with sympatric S. canis populations must focus on human-to-human transmission.
131 citations
TL;DR: Results of in vitro permethrin exposure assays showed that survival rates for mites bearing the mutation were similar to those previously reported formites from human subjects where clinical tolerance topermethrin had been observed.
Abstract: Permethrin as a topical acaricide cream is widely used to treat scabies The neuronal voltage-sensitive sodium channel (Vssc), necessary for the generation of action potentials in excitable cells, is the target of pyrethroid acaricides such as permethrin Pyrethroid resistance has been linked to specific mutations in the Vssc gene Following the partial sequencing of the Vssc gene in the scabies mite Sarcoptes scabiei (L) (Astigmata: Sarcoptidae), we compared Vssc gene sequences from permethrin-sensitive and -tolerant S scabiei var canis Gerlach mites, and identified a G to A single nucleotide polymorphism (SNP) in permethrin-tolerant mites resulting in an amino acid change from glycine to aspartic acid in domain III S6 The mutation is in a region of the gene where mutations have been identified in a range of pyrethroid-resistant arthropods Results of in vitro permethrin exposure assays showed that survival rates for mites bearing the mutation were similar to those previously reported for mites from human subjects where clinical tolerance to permethrin had been observed A real-time polymerase chain reaction−high-resolution melt (PCR-HRM) assay was developed to detect this SNP This assay provides a useful methodology for screening for this and other mutations associated with permethrin resistance in scabies mite populations and thus facilitates surveillance for acaricide resistance
113 citations
1 Jan 1968
85 citations
TL;DR: Although the majority of recurrent scabies is probably due to reinfestation from inadequately treated contacts, there was evidence that in very severe crusted scabies, treatment with even 3 doses of ivermectin 14 days apart may be inadequate and relapse may occur.
Abstract: Crusted scabies is a severe debilitating disease due to hyperinfestation with the ectoparasite Sarcoptes scabiei. Treatment protocols include oral ivermectin and topical scabicides. After single-dose ivermectin, there may be early recrudescence, whereas after 3 doses at 14-day intervals, there is an apparent cure. However, such patients often present again after 6-12 months. To clarify the biology of recurrence, we studied genetic markers in sequential populations of S. scabiei mites from treated patients with multiple episodes of crusted scabies. Individual mites were genotyped at hypervariable microsatellite loci by a fluorescence-based polymerase chain reaction. Results indicated that sequential populations of mites were genetically more similar to each other than to mites from other patients. Although the majority of recurrent scabies is probably due to reinfestation from inadequately treated contacts, there was evidence that in very severe crusted scabies, treatment with even 3 doses of ivermectin 14 days apart may be inadequate and relapse may occur.
77 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 1 |
| 2020 | 5 |
| 2019 | 1 |
| 2016 | 2 |
| 2015 | 4 |
| 2014 | 4 |