Sarcoptes scabiei mites in humans are distributed into three genetically distinct clades

AbstractScabies is an ectoparasitic infestation caused by the mite Sarcoptes scabiei. Currently, S. scabiei is taxonomically divided into different varieties on the basis of host origin. Genetics-based research on scabies has been conducted, but the data on genetic diversity of populations of this mite in humans in Europe are lacking. We evaluated the genetic diversity of populations of S. scabiei. A large series of mites obtained from humans in France and the data of mites from various hosts and geographical areas retrieved from GenBank were included to investigate whether mites are divided into distinct populations. The study of cytochrome c oxidase subunit 1 gene polymorphisms were found to be best suited for phylogenetic analysis. S. scabiei mites were distributed into three genetically distinct clades, with most mites clustering in clades B and C. The Fst value and the Nm value calculated for mites included in clades B and C indicated a strong population structure and a very low gene flow between mites of those clades. The results of the present study not only support the rejection of the hypothesis of panmixia for S. scabiei in humans but also suggest that mites belonging to different clades are genetically isolated. Moreover, the results suggest that the subdivision of S. scabies in varieties according to animal or human hosts is not warranted. In conclusion, S. scabiei mites in humans do not constitute a homogeneous population. Further investigations are now required to assess whether different clinical forms of scabies are associated with particular haplotypes or clades

Toward the Global Control of Human Scabies: Introducing the International Alliance for the Control of Scabies

Scabies, the human skin disease caused by infestation by the mite Sarcoptes scabiei var. hominis, causes considerable morbidity and mortality through direct effects and as a result of secondary bacterial infection. Scabies is a truly neglected disease, largely absent from the global health agenda, and its huge burden of disease is largely underappreciated. We contend that coordinated, global efforts to control this ubiquitous pathogenic mite are both important and achievable

International recommendations for an effective control of head louse infestations

Head louse infestations continue to be a concern of public health in most countries, including the most developed ones. The present recommendations are intended to inform and stress the role and impact of the different authorities, institutions, industry, and the public in the control of head lice in order to reduce the prevalence of this parasite. We encourage health authorities to pursue more effective methods to correctly identify such infestations, and evaluate existing and new pediculicides, medical devices, louse repellents, and louse- and nit-removal remedies. Pediculicides and medical devices must have verifiable claims in the instructions for use and should be tested periodically to document current levels of resistance by lice to the active ingredients and to the formulated products. Where the prevalence of lice is claimed to be epidemic, children should be periodically evaluated objectively to document the actual level of prevalence. Continuing education for health providers and the general population promises to correct misinformation regarding the biology, prevention, and management of lice. Parents should regularly inspect their children for head lice and treat as necessary. Health authorities are encouraged to eliminate policies and practices that rely upon school exclusion as a means to reduce incidence and prevalence, e.g., the ‘no-nit’ policy which lacks scientific justification, and are counterproductive to the health and welfare of childrenFil: Mumcuoglu, Kosta Y.. The Hebrew University of Jerusalem; IsraelFil: Pollack, Richard J.. Harvard University; Estados UnidosFil: Reed, David L.. University Of Florida. Florida Museum Of History; Estados UnidosFil: Barker, Stephen C.. University of Queensland; AustraliaFil: Gordon, Shirley. Florida Atlantic University; Estados UnidosFil: Toloza, Ariel Ceferino. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación de Plagas e Insecticidas; ArgentinaFil: Picollo, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación de Plagas e Insecticidas; ArgentinaFil: Taylan Ozkan, Aysegul. Hitit University; Turquía. Near East University; ChipreFil: Chosidow, Olivier. Hôpital Henri Mondor; FranciaFil: Habedank, Birgit. German Environment Agency; AlemaniaFil: Ibarra, Joanna. Community Hygiene Concern; Reino UnidoFil: Meinking, Terri L.. Global Health Associates of Miami; Estados UnidosFil: Vander Stichele, Robert H.. Heymans Institute of Pharmacology; Bélgic

Diagnostics to support the control of scabies-Development of two target product profiles.

BACKGROUND: Scabies was added to the WHO NTD portfolio in 2017 and targets for the control of scabies were included in the 2021-2030 WHO NTD roadmap. A major component of scabies control efforts a strategy based on mass drug administration (MDA) with ivermectin. Currently diagnosis of scabies relies on clinical examination with a limited role for diagnostic testing. Under the recommendation of the WHO Diagnostic Technical Advisory Group (DTAG) for Neglected Tropical Diseases, a working group was assembled and tasked with agreeing on priority use cases for and developing target product profiles (TPPs) for new diagnostics tools for scabies. METHODOLOGY AND PRINCIPAL FINDINGS: The working group convened three times and established two use cases: establishing if the 10% threshold for mass drug administration had been reached and if the 2% threshold for stopping mass drug administration has been achieved. One subgroup assessed the current diagnostic landscape for scabies and a second subgroup determined the test requirements for both use cases. Draft TPPs were sent out for input from stakeholders and experts. Both TPPs considered the following parameters: product use, design, performance, configuration, cost, access and equity. The group considered the use of the tests as a single step process or as part of a two step process following initial clinical examination. When used a single step test (the ideal scenario) for starting MDA a new diagnostic required a sensitivity of ≥92% and a specificity of ≥98%. When used a single step test (the ideal scenario) for stopping MDA a new diagnostic required a sensitivity of ≥80% and a specificity of ≥99%. CONCLUSIONS: The TPPs developed will provide test developers with guidance to ensure that novel diagnostic tests meet identified public health needs

Randomised, Controlled, Assessor Blind Trial Comparing 4% Dimeticone Lotion with 0.5% Malathion Liquid for Head Louse Infestation

BACKGROUND:Malathion 0.5% has been the most prescribed pediculicide in the United Kingdom for around 10 years, and is widely used in Europe and North America. Anecdotal reports suggest malathion treatments are less effective than formerly, but this has not been confirmed clinically. This study was designed to determine whether malathion is still effective and if 4% dimeticone lotion is a more effective treatment for head louse infestation. METHODOLOGY/PRINCIPAL FINDINGS:We designed this study as an assessor blinded, randomised, controlled, parallel group trial involving 58 children and 15 adults with active head louse infestation. Each participant received two applications 7 days apart of either 4% dimeticone lotion, applied for 8 hours or overnight, or 0.5% malathion liquid applied for 12 hours or overnight. All treatment and check-up visits were conducted in participants' homes. Cure of infestation was defined as no evidence of head lice after the second treatment. Some people were found free from lice but later reinfested. Worst case, intention to treat, analysis found dimeticone was significantly more effective than malathion, with 30/43 (69.8%) participants cured using dimeticone compared with 10/30 (33.3%) using malathion (p<0.01, difference 36.4%, 95% confidence interval 14.7% to 58.2%). Per protocol analysis showed cure rates of 30/39 (76.9%) and 10/29 (34.5%) respectively. Irritant reactions were observed in only two participants, both treated with malathion. CONCLUSIONS/SIGNIFICANCE:We concluded that, although malathion liquid is still effective for some people, dimeticone lotion offers a significantly more effective alternative treatment for most people. TRIAL REGISTRATION:Controlled-Trials.com ISRCTN47755726

Antitumour necrosis factor-α therapy for hidradenitis suppurativa: results from a national cohort study between 2000 and 2013

International audienceHidradenitis suppurativa (HS) is a frequent chronic inflammatory skin disease typically characterized by recurrent painful, deep inflammatory nodules of the axillary, breast, groin and gluteal areas. European recommendations are mainly based on expert opinion. Drug treatments are heterogenous (e.g., antibiotics, corticosteroids, retinoids) and lack consensus among expert centres. The most severe disease forms or those failing to respond to conventional drugs may be associated with worsened functional prognosis. Anti-tumor necrosis factor α (anti-TNFα) drugs have been prescribed in these cases. The results of randomized controlled trials (RCTs) are discordant. Three RCTs concluded to the efficacy of adalimumab (ADA), and two others did not detect any difference between infliximab (IFX) or etanercept (ETA) and placebo. Finally, data from the literature and reported experiences do not conclude on the efficacy of anti-TNFα drugs for HS. This article is protected by copyright. All rights reserve