European guideline for the management of scabies

Scabies vaccines: where we stand and challenges ahead

Scabies is an itchy skin disease caused by the burrowing mite, Sarcoptes scabiei. During their lifespan, female mites invade the stratum corneum and create tunnels in which they reside, move, feed, deposit fecal pellets, and lay eggs. Globally, more than 200 million people are estimated to be affected by scabies annually. Currently, using scabicidal agents is the only approved method for treating scabies. However, resistance to commonly used agents such as permethrin and ivermectin has been observed in scabies mites. Therefore, the development of vaccines for scabies, either as a preventative measure or for treatment, is crucial to control such neglected diseases. Since the host could evolve a protective immune response that could prevent re-infestation by scabies mites, vaccine development is theoretically possible. This review aims to provide a comprehensive overview of the ongoing challenges regarding the currently available control measures for scabies. It also explores the promising path of scabies vaccine development, highlighting the current state of research and challenges that need to be addressed to develop new and innovative measures for both treating and preventing scabies infections.

Clinical practice guidelines for the diagnosis and treatment of scabies

Scabies, caused by the Sarcoptes scabiei var hominis mite burrowing into the skin, is a highly contagious disease characterized by intense nocturnal itching. Its global impact is considerable, affecting more than 200 million individuals annually and posing significant challenges to healthcare systems worldwide. Transmission occurs primarily through direct skin-to-skin contact, contributing to its widespread prevalence and emergence as a substantial public health concern affecting large populations. This review presents consensus-based clinical practice guidelines for diagnosing and managing scabies, developed through the fuzzy Delphi method by dermatology, parasitology, pediatrics, pharmacology, and public health experts. The presence of burrows containing adult female mites, their eggs, and excreta is the diagnostic hallmark of scabies. Definitive diagnosis typically involves direct microscopic examination of skin scrapings obtained from these burrows, although dermoscopy has become a diagnostic tool in clinical practice. Treatment modalities encompass topical agents, such as permethrin, balsam of Peru, precipitated sulfur, and benzyl benzoate. In cases where topical therapy proves inadequate or in instances of crusted scabies, oral ivermectin is recommended as a systemic treatment option. This comprehensive approach addresses the diagnostic and therapeutic challenges associated with scabies, optimizing patient care, and management outcomes.

Traditional healers' perception on scabies causation and management in Ghana

INTRODUCTION

Scabies is an underdiagnosed skin infestation caused by the Sarcoptes scabiei mite. The infection causes severe itching and a skin rash but can be effectively treated using topical or systemic drugs. Scabies outbreaks are commonly reported in resource-poor countries, including Ghana. Traditional healers play an important role in primary care in rural areas. The role of these traditional healers in the management of scabies has so far not been explored. The aim of this study was therefore to investigate the perceptions of traditional healers regarding the causation and management of scabies.

METHODS

A phenomenological qualitative approach was employed. Traditional healers in the Asante Akim North and Central districts in Ghana were approached with an interview request. Using a semi-structured interview protocol, 15 traditional healers were interviewed. The results were coded and analysed, after which seven themes were extrapolated.

RESULTS

Scabies infections were frequently reported by traditional healers. Itching and skin rash were unanimously regarded as the major symptoms of scabies. The majority acknowledged the infectious nature of scabies, but no participant reported the causative organism. A dichotomous disease classification was noted, consisting of 'natural' and 'spiritual' variants each with a unique disease profile and management requirements, as reported by the traditional healers. All but two traditional healers reported to treat scabies using almost exclusively herbs and spiritual rituals.

CONCLUSION

The majority of traditional healers were open to collaboration with allopathic healthcare providers. Collaboration could broaden the primary care network in rural areas, but mistrust and lack of transparency form potential barriers to collaboration. We, therefore, emphasise the need for additional efforts to investigate strategies for future collaboration.

Scabies in infants and children - a narrative review

Scabies is a human ectoparasitosis caused by Sarcoptes scabei var. hominis. World-wide around 300 million patients are affected. Infants and children have the highest incidence rates. Poverty and overcrowding are social factors contributing to a higher risk of transmission and treatment failure. The leading symptom of the infestation is itch. Complications are bacterial infections that are responsible for mortality. Diagnosis is clinical. Non-invasive imaging technologies like dermoscopy can be used. Polymerase chain reaction (PCR) is less sensitive and specific than microscopy of skin scrapings. Treatment of choice is topical permethrin 5%. Ivermectin is the only oral drug FDA-approved for scabies. It should be used in cases non-responsive to topical therapy and in case of high number of infested patients in addition to topical therapy. Pseudo-resistance to treatment is not uncommon. New drugs are on the horizon. What is Known: • Pruritus is the leading symptom causing sleep disturbances and scratching with the risk of secondary bacterial infections. • Treatment failure is related to inappropriate application of topical drugs and asymptomatic family members. What is New: • COVID-19 pandemic and migration are contributing to an increased incidence of scabies. • New compounds to treat scabies are on the horizon.

Spanish Academy of Dermatology and Venereology (AEDV) expert recommendations for the management of sexual transmitted parasitosis. Scabies, and pediculosis pubis

Sexually transmitted infections are communicable diseases where the pathogen is transmitted through sexual contact. The Sexually Transmitted Infections Working Group of the Spanish Academy of Dermatology and Venereology (AEDV) is engaged in the drafting of documents to guide dermatologists and health care personnel who treat Spanish patients with these infections. This document analyzes the epidemiological, clinical, therapeutic, and control characteristics of 2 sexually transmitted parasitosis: scabies due to Sarcoptes scabiei var. hominis, and pubic pediculosis due to Phthirus pubis. Both parasitoses share a sort of mixed spread through sexual and community transmission regardless of the route through which the infection was initially acquired. This specific feature creates particularities in the management and control of the infestation.

[Translated article] Spanish Academy of Dermatology and Venereology (AEDV) expert recommendations for the management of sexual transmitted parasitosis. Scabies, and pediculosis pubis

Sexually transmitted infections are communicable diseases where the pathogen is transmitted through sexual contact. The Sexually Transmitted Infections Working Group of the Spanish Academy of Dermatology and Venereology (AEDV) is engaged in the drafting of documents to guide dermatologists and health care personnel who treat Spanish patients with these infections. This document analyzes the epidemiological, clinical, therapeutic, and control characteristics of 2 sexually transmitted parasitosis: scabies due to Sarcoptes scabiei var. hominis, and pubic pediculosis due to Phthirus pubis. Both parasitoses share a sort of mixed spread through sexual and community transmission regardless of the route through which the infection was initially acquired. This specific feature creates particularities in the management and control of the infestation.

Frequent Misdiagnosis of Scabies as Eczema in China: A Descriptive Study of 23 Cases

Objective

To outline the clinical manifestations observed in patients with scabies misdiagnosed as generalized eczema, analyse the factors contributing to these misdiagnoses and explore potential reasons for the resurgence of scabies.

Patients and Methods

A retrospective analysis was performed to investigate the patients with scabies misdiagnosed as generalized eczema.

Results

We included 23 patients, with twelve (52.17%) being male and eleven (47.83%) female. The illness duration ranged from 0.5 to 7 months. Among all patients, 12 (52.17%) were residents of nursing homes, 5 (21.74%) were staff members of these facilities, 4 (17.39%) were caregivers of long-term hospitalized relatives, 1 (4.35%) was a construction worker, and 1 (4.35%) had a history of tourism. The rash predominantly affected the trunk and extremities, 12 patients (52.17%) are each involved the perineum and fingers webbings. The presentations included erythema, papules, and nodules. The main complaint of all patients was nocturnal itch. Under direct microscopy, 5 patients (21.74%) tested positive for scabies mites, and 3 (13.04%) showed histopathological features consistent with scabies. All patients were initially misdiagnosed with generalized eczema.

Conclusion

Over half of all patients diagnosed with scabies either resided or worked in long-term care facilities. The lack of awareness of scabies among medical staff in long-term care facilities readily led to frequent misdiagnosis. Comprehensive measures should be implemented urgently to strengthen disease management.

Scabies in Infants: Series of 51 Cases

We conducted a two-year retrospective evaluation of infants aged under two years with a confirmed, clinical, or suspected diagnosis of scabies in a healthcare center in Alicante (Spain) to determine possible factors associated with diagnostic delay and poor treatment response. We collected epidemiological, clinical, diagnostic, and treatment variables. After describing our findings as mean values and percentages, we compared categorical variables using the Student's t-test and the Mann-Whitney U test, and we compared continuous variables with the Chi2 test and Pearson's correlation coefficient. We included 51 infants (19 boys and 32 girls) with a mean age of 15 months. The main source of contagion was the family; half of the infants lived with four or more people. According to the International Consensus Criteria for the Diagnosis of Scabies, confirmed scabies was diagnosed in 45% of cases and clinical scabies in 47%, and 45% of cases had a diagnostic delay. Lesions mainly affected the hands, feet, and trunk, with papules in 92% of cases and burrows in 55%. The predominant symptoms were pruritus (94%) and irritability (69%). Regarding treatment, 98% of the infants received topical permethrin and 35% received oral ivermectin. Treatment failed in 76% of infants. Living in large family units was associated with a higher risk of contagion and therapeutic failure. Diagnostic delay was associated with previous misdiagnosis.

Comparison of topical permethrin 5% vs. benzyl benzoate 25% treatment in scabies: a double-blinded randomized controlled trial

BACKGROUND

Scabies is a pruritic parasitic infestation of the skin. High-income countries have reported an increasing incidence over the last few years. Studies have indicated a reduction in the sensitivity of scabies mites to the standard treatment of choice, topical permethrin 5%.

OBJECTIVES

To evaluate in a head-to-head manner the efficacy of two topical scabicides [permethrin 5% and benzyl benzoate 25% (BB)] in the treatment of scabies using the same administration modality; and to address potential confounding factors such as incorrectly performed treatment and hygiene measures.

METHODS

In total, 110 patients with dermoscopy-verified scabies infestation were enrolled and randomized into two equally sized groups in a double-blinded manner. Fifty-five received topical permethrin 5% and 55 received topical BB 25%, both for daily use over a period of three consecutive days. Treatment outcome was evaluated by dermoscopy at a 3-week follow-up visit.

RESULTS

Treatment resulted in a dermoscopy-verified cure rate of 27% in the permethrin group and 87% in the BB group. The tolerability and safety profile of permethrin 5% cream was excellent, while the BB emulsion produced a burning sensation in 43% of patients.

CONCLUSIONS

Topical permethrin demonstrated a lack of efficacy in the majority of scabies cases, whereas BB demonstrated an excellent cure rate and reasonable tolerability. Considering the reduced sensitivity of scabies mites to permethrin 5%, our results suggest that BB is an appropriate first-line therapy in the treatment of scabies.

Scabies in French Guiana: Quantitative and qualitative factors associated with therapeutic failure

BACKGROUND

Strategies for the control of scabies should be adapted to local settings. Traditional communities in French Guiana have non-Western conceptions of disease and health.

OBJECTIVES

The objectives for this study were to explore knowledge, attitudes and practices to identify potential factors associated with the failure of scabies treatment in these communities.

METHODS

Patients with a clinical diagnosis of scabies, seen at either the Cayenne Hospital or one of 13 health centres between 01 April 2021 and 31 August 2021, were included as participants, and were seen again after 6 weeks to check for persistence of lesions. Factors associated with treatment failure were looked for both at inclusion and at 6 weeks. Semi-structured interviews were conducted with a diversified subsample of participants.

RESULTS

In total, 164 participants were included in the quantitative component, and 21 were interviewed for the qualitative component. Declaring that the second treatment dose had been taken was associated with therapeutic success. Western treatments were not always affordable. Better adherence was observed with topical treatments than with oral ivermectin, whereas permethrin monotherapy was associated with failure. Scabies-associated stigma was high among Amerindians and Haitians but absent in Ndjuka Maroons. Participants reported environmental disinfection as being very complex.

CONCLUSIONS

The treatment of scabies in traditional Guianan communities may vary depending on local perceptions of galenic formulations, disease-associated stigma and differences in access to health care. These factors should be taken into account when devising strategies for the control of scabies aimed at traditional communities living in remote areas, and migrant populations.

Failure of scabies treatment: a systematic review and meta-analysis

BACKGROUND

Treatment failure is considered to be an important factor in relation to the increase in scabies incidence over the last decade. However, the regional and temporal differences, in addition to the predictors of therapy failure, are unclear.

OBJECTIVES

We aimed to conduct a systematic review of the prevalence of treatment failure in patients with scabies and investigation of associated factors.

METHODS

We searched MEDLINE, EMBASE, CINAHL, Web of Science, Scopus, Global Health and the Cochrane Central Register of Controlled Trials from inception to August 2021 for randomized and quasi-randomized trials, in addition to observational studies that enrolled children or adults diagnosed with confirmed or clinical scabies treated with permethrin, ivermectin, crotamiton, benzyl benzoate, malathion, sulfur or lindane, and measured treatment failure or factors associated with treatment failure. We performed a random effects meta-analysis for all outcomes reported by at least two studies.

RESULTS

A total of 147 studies were eligible for inclusion in the systematic review. The overall prevalence of treatment failure was 15.2% [95% confidence interval (CI) 12.9-17.6; I2 = 95.3%, moderate-certainty evidence] with regional differences between World Health Organization regions (P = 0.003) being highest in the Western Pacific region (26.9%, 95% CI 14.5-41.2). Oral ivermectin (11.8%, 95% CI 8.4-15.4), topical ivermectin (9.3%, 95% CI 5.1-14.3) and permethrin (10.8%, 95% CI 7.5-14.5) had relatively lower failure prevalence compared with the overall prevalence. Failure prevalence was lower in patients treated with two doses of oral ivermectin (7.1%, 95% CI 3.1-12.3) compared with those treated with one dose (15.2%, 95% CI 10.8-20.2; P = 0.021). Overall and permethrin treatment failure prevalence in the included studies (1983-2021) increased by 0.27% and 0.58% per year, respectively. Only three studies conducted a multivariable risk factor analysis; no studies assessed resistance.

CONCLUSIONS

A second dose of ivermectin showed lower failure prevalence than single-dose ivermectin, which should be considered in all guidelines. The increase in treatment failure over time hints at decreasing mite susceptibility for several drugs, but reasons for failure are rarely assessed. Ideally, scabicide susceptibility testing should be implemented in future studies.

Scabies in Spain: Trends in Public Interest and Ectoparasiticide Use

Scabies is an ectoparasitic dermatosis caused by the Sarcoptes scabiei var. hominis mite, which lives and reproduces in humans. Its incidence in Spain has increased in recent years. The aim of this study was to complement existing evidence on the increasing number of scabies cases in our country by analyzing changes in ectoparasiticide prescriptions and Internet searches for scabies infestations measured by Google Trends. We also examined correlations between these two variables. Our results show that public interest in scabies has increased in recent years and is positively and significantly correlated with an increasing use of ectoparasiticides. We believe that Google Trends should be considered as a complementary tool for monitoring real-time trends in scabies infestations in Spain.

[Translated article] Scabies in Spain: Trends in Public Interest and Ectoparasiticide Use

Scabies is an ectoparasitic dermatosis caused by the Sarcoptes scabiei var. hominis mite, which lives and reproduces in humans. Its incidence in Spain has increased in recent years. The aim of this study was to complement existing evidence on the increasing number of scabies cases in our country by analyzing changes in ectoparasiticide prescriptions and Internet searches for scabies infestations measured by Google Trends. We also examined correlations between these two variables. Our results show that public interest in scabies has increased in recent years and is positively and significantly correlated with an increasing use of ectoparasiticides. We believe that Google Trends should be considered as a complementary tool for monitoring real-time trends in scabies infestations in Spain.

Comment on 'Permethrin-unresponsive scabies in London, UK: a wake-up call'

Regarding scabies management, permethrin is the most prescribed first-line treatment. However, cases of treatment resistance have been reported, leading to the need for new drugs.

National survey in Switzerland calls for improved diagnosis and treatment in children with scabies

AIM OF THE STUDY

The global prevalence of scabies is estimated to be up to 200 million cases annually, with young children particularly affected. In Europe, most cases are thought to originate in migrant populations. Scabies management is challenging in children. To identify knowledge gaps and research needs, we aimed to descriptively evaluate the management of children with scabies by different Swiss healthcare providers.

METHODS

An invitation for an anonymous online survey (36 questions) was sent to members of Swiss societies of dermatologists, general practitioners, paediatricians, paediatric dermatologists, paediatric infectious diseases specialists, and tropical medicine specialists, inviting clinicians to participate from 25th May to 8th August 2020. One reminder invitation was sent. Hospital pharmacies and the distributor of permethrin were contacted to report consumption trends of scabicides in 2018 and 2019.

RESULTS

The survey was completed by 248 clinicians: 146 (59%) paediatricians, 47 (19%) dermatologists, 28 (11%) general practitioners, 6 (2%) paediatric dermatologists, 13 (5%) paediatric infectious diseases specialists, and 8 (3%) tropical medicine specialists. Most consulted up to 10 scabies cases within a 16-month period, with similar numbers in migrant and Swiss children. Dermoscopy was used by 24% of non-dermatologists. Non-dermatologists did not consider co-treatment of close contacts in up to 59% of cases. While permethrin was the first-line treatment, treatment failures were frequently reported in children aged <5 years. Up to 67% of paediatric dermatologists regularly used oral ivermectin off-label in children weighing <15 kg. None of the paediatric dermatologists, 15% of the dermatologists, and 9% of the non-dermatologists used only one treatment cycle.Scabicide consumption increased. Treatment studies on ivermectin use in children weighing <15 kg had the highest research priority.

CONCLUSION

In Switzerland, scabies is a frequent dermatosis in migrant and Swiss children. While accessible, optimal diagnostics are underutilised, and treatment is suboptimal. Permethrin resistance appears to be an increasing problem. Dermatologists regularly use ivermectin off-label in children weighing <15 kg. Treatment studies on ivermectin use in children weighing <15 kg, user-friendly diagnostic tools, new treatment protocols, and child-friendly dosage forms are needed to improve the diagnosis and treatment of children with scabies.

Scabies outbreak management in refugee/migrant camps in Europe 2014-2017: a retrospective qualitative interview study of healthcare staff experiences and perspectives

OBJECTIVES

Provide insights into the experiences and perspectives of healthcare staff who treated scabies or managed outbreaks in formal and informal refugee/migrant camps in Europe 2014-2017.

DESIGN

Retrospective qualitative study using semistructured telephone interviews and framework analysis. Recruitment was done primarily through online networks of healthcare staff involved in medical care in refugee/migrant settings.

SETTING

Formal and informal refugee/migrant camps in Europe 2014-2017.

PARTICIPANTS

Twelve participants (four doctors, four nurses, three allied health workers, one medical student) who had worked in camps (six in informal camps, nine in formal ones) across 15 locations within seven European countries (Greece, Serbia, Macedonia, Turkey, France, the Netherlands, Belgium).

RESULTS

Participants reported that in camps they had worked, scabies diagnosis was primarily clinical (without dermatoscopy), and treatment and outbreak management varied highly. Seven stated scabicides were provided, while five reported that only symptomatic management was offered. They described camps as difficult places to work, with poor living standards for residents. Key perceived barriers to scabies control were (1) lack of water, sanitation and hygiene, specifically: absent/limited showers (difficult to wash off topical scabicides), and inability to wash clothes and bedding (may have increased transmission/reinfestation); (2) social factors: language, stigma, treatment non-compliance and mobility (interfering with contact tracing and follow-up treatments); (3) healthcare factors: scabicide shortages and diversity, lack of examination privacy and staff inexperience; (4) organisational factors: overcrowding, ineffective interorganisational coordination, and lack of support and maltreatment by state authorities (eg, not providing basic facilities, obstruction of self-care by camp residents and non-governmental organisation (NGO) aid).

CONCLUSIONS

We recommend development of accessible scabies guidelines for camps, use of consensus diagnostic criteria and oral ivermectin mass treatments. In addition, as much of the work described was by small, volunteer-staffed NGOs, we in the wider healthcare community should reflect how to better support such initiatives and those they serve.

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.

The Detrimental Effect of Pre-Treatment with Ivermectin on Myocardial Ischemia

INTRODUCTION

Ivermectin (IVM) is a broad-spectrum anti-parasitic agent with potential antibacterial, antiviral, and anti-cancer effects. There are limited studies on the effects of IVM on cardiovascular diseases, so the present study sought to determine the effects of pre-treatment with IVM on myocardial ischemia in both ex vivo and in vivo.

METHODS

In the ex vivo part, two groups of control and treated rats with IVM (0.2 mg/kg) were examined for cardiac function and arrhythmias by isolated heart perfusion. In the in vivo part, four groups, namely, control, IVM, Iso (MI), and Iso + IVM 0.2 mg/kg were used. Subcutaneous injection of isoproterenol (100 mg/kg/day) for 2 consecutive days was used for the induction of myocardial infarction (MI) in male Wistar rats. Then electrocardiogram, hemodynamic factors, cardiac hypertrophy, and malondialdehyde (MDA) levels were investigated.

RESULTS

The ex vivo results showed that administration of IVM induces cardiac arrhythmia and decreases the left ventricular maximal rate of pressure increase (contractility) and maximal rate of pressure decline (relaxation). The isoproterenol-induced MI model used as an in vivo model showed that cardiac hypertrophy were increased with no improvement in the hemodynamic and electrocardiogram pattern in the IVM-treated group in comparison to MI (Iso) group. However, the MDA level was lower in the IVM-treated group.

CONCLUSION

IVM pre-treatment demonstrates detrimental effects in cardiac ischemia through exacerbation of cardiac arrhythmia, myocardial dysfunction, and increased cardiac hypertrophy. Therefore, the use of IVM in ischemic heart patients should be done with great caution.

Infection Control among Healthcare Workers and Management of a Scabies Outbreak in a Large Italian University Hospital

This retrospective observational study describes the results of an ad-hoc designated prevention protocol aimed at containing the spread of the scabies infestation among healthcare workers (HCWs) of a large University Hospital in Italy. The outbreak started on October 2022 and a preventive protocol was set up thanks to a multidisciplinary approach. HCWs at high scabies risk were defined as subjects working in Operative Units with a scabies prevalence higher than 2%, close contacts of a confirmed case of scabies, or HCWs with signs and symptoms of the disease. All cases at high scabies risk underwent a dermatological examination, and the infested HCWs were suspended from work until definitive healing. Mass drug administration was established for all HCWs working in Operative Units with a scabies prevalence higher than 2%. Until March 2023, out of 183 screening dermatological examinations, 21 (11.5%) were diagnostic for scabies. Between 11 October 2022 (date of the first diagnosed scabies case) and 6 March 2023 (the end of incubation period related to the last case detected), the frequency of scabies was 0.35% (21 scabies cases/6000 HCWs). The duration of the outbreak in our hospital was 14.7 weeks. Statistical analysis shows a significant association between scabies and being a nurse and having an allergy to dust mites. We obtained a low frequency of scabies infection, limiting the duration of the outbreak and the related economic burden.

The current available diagnostic tools and treatments of scabies and scabies variants: An updated narrative review

Scabies is a neglected tropical disease that continues to have global impacts and long-term health consequences. It is caused by the mite Sarcoptes scabei var. hominis, which is an obligate ectoparasite that lives in the epidermis of the human skin. Scabies is common in poor communities due to overcrowding in places like old age homes, prisons, and homeless and displaced children. However, developed countries are also susceptible to scabies infestations, such as in institutional outbreaks or small epidemics under war conditions or during natural disasters. The diagnosis of scabies may be assisted by invasive and noninvasive tools; However, the history and examination findings are usually adequate to confirm the clinical suspicion. Here, we present an updated review of scabies by focusing on the diagnostic approaches, treatment, and prevention of scabies.

Can Ivermectin kill Sarcoptes scabiei during the molting process?

BACKGROUND

Sarcoptes scabiei is a permanent obligate ectoparasite that lives and reproduces in the epidermis of humans and other mammals worldwide. There is a lack of information on the molting process of Sarcoptes scabiei. Ivermectin is widely used to treat Sarcoptes infection in humans and animals, while the survival of molting Sarcoptes mites in the presence of ivermectin is unknown. The aim of the present study is to investigate the molting process of Sarcoptes mites and assess the activity of ivermectin during the molting process of Sarcoptes mites.

METHODOLOGY/PRINCIPAL FINDINGS

molting Sarcoptes mites were incubated at 35°C and 80% relative humidity and observed hourly until complete molt. Of the 192 molting mites recorded, the longest molt periods for larvae and nymphs were 23 and 30 h, respectively. The activity of ivermectin on molting Sarcoptes mites was also assessed using two concentrations of the drug (0.1 and 0.05 mg/ml). The exposure time for molting mites was determined by 100% mortality of female mites exposed to the solution of ivermectin. While all female mites were killed after exposure to 0.1 mg/ml ivermectin for 2 h and and 0.05 mg/ml for 7 h, 32% and 36% of molting mites survived and successfully molted, respectively.

CONCLUSIONS/SIGNIFICANCE

The present study demonstrated that molting Sarcoptes mites are less susceptible to ivermectin than active mites. As a consequence, mites may survive after two doses of ivermectin given 7 days apart due not only to hatching eggs but also to the resistance of mites during their molting process. Our results provide insight into the optimal therapeutic regimens for scabies and highlight the need for further research on the molting process of Sarcoptes mites.

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Study of the Use of Permethrin 5% Cream in Galicia (Spain) between 2018 and 2021

Drug utilization studies can provide direct insights into how a drug is used in real-world conditions and can give a rough estimate of the proportion of the study population treated with it. In the present work, we examined the consumption of permethrin 5% cream in the four provinces of Galicia (a Spanish autonomous community) and described the seasonal variability and the annual evolution of its consumption between 2018 and 2021. A descriptive, cross-sectional, and retrospective study of the consumption of this drug, expressed in defined daily dose per 1000 inhabitants per day (DID), was carried out. The results obtained revealed differences between the amounts consumed in the four Galician provinces (p < 0.001). No specific geographical pattern was observed; however, the results suggested a marked seasonality and a slightly increasing global trend in the consumption of permethrin 5% cream throughout the study period. Since the only authorized indication of this drug in the study area is the treatment of scabies, this work may give an idea of the epidemiological situation of the disease in Galicia and serve to establish public health strategies against this parasitosis.

Severe Scabies: A French Multi-centre Study Involving 95 Patients with Crusted and Profuse Disease and Review of the Literature

The aim of this multi-centre French retrospective study was to identify severe, i.e. crusted and profuse, scabies patients. Records were retrieved from 22 Dermatology or Infectious Diseases departments in the Ile-de-France from January 2009 to January 2015 to characterize epidemiology, demography, diagnosis, contributing factors, treatment features, and outcomes in severe scabies. A total of 95 inpatients (57 crusted and 38 profuse) were included. A higher number of cases was observed among elderly patients (>75 years), mostly living in institutions. Thirteen patients (13.6%) reported a history of previously treated scabies. Sixty-three patients (66.3%) had been seen by a previous practitioner for the current episode (up to 8 previous visits). Initial misdiagnosis (e.g. eczema, prurigo, drug-related eruptions, psoriasis) was documented in 41 patients (43.1%). Fifty-eight patients (61%) had already received 1 or more previous treatments for their current episode. Forty percent received corticosteroids or acitretin for an initial diagnosis of eczema or psoriasis. Median time from the onset of symptoms to the diagnosis of severe scabies was 3 months (range 0.3-22). Itch was present in all patients at diagnosis. Most patients (n=84, 88.4%) had comorbidities. Diagnostic and therapeutic approaches varied. Complications occurred in 11.5% of cases. To date, there is no consensus for diagnosis and treatment, and future standardization of is required for optimal management.

Oral ivermectin to treat scabies: a comparison of two different regimens

As Sarcoptes scabiei is becoming less sensitive to permethrin, clinicians have started to prescribe oral ivermectin (OI) as a first-line treatment. Guidelines suggest OI 200 µg kg-1 as two doses, 1 week apart. However, the black box of the ivermectin registered in Italy recommends a single dose. To compare these two regimens, we collected 71 cases of scabies and treated them according to this protocol [single-dose group (SDG)]. This population was compared to 68 patients who received two doses 1 week apart [double-dose group (DDG)]. Clearance of the disease was achieved in 98% of DDG patients. In the SDG, treatment was successful in only 58% of patients. This study confirms that the absence of a second intake of OI is one of the main predictors of treatment failure (P < 0.001), which may also increase the likelihood of emerging resistance in S. scabiei.

Beliefs, attitudes and practices towards scabies in central Ghana

BACKGROUND

Scabies commonly affects poor populations in low-middle-income countries. The WHO has advocated for country-driven and country-owned control strategies. Knowledge of context specific issues will be important for design and implementation of scabies control interventions. We aimed to assess beliefs, attitudes and practices towards scabies in central Ghana.

METHODOLOGY/PRINCIPAL FINDINGS

Data was collected via semi-structured questionnaires for people who had active scabies or scabies in the past year and people who never had scabies in the past. The questionnaire covered several domains: knowledge about the causes and risk factors; perceptions towards stigmatisation and consequences of scabies in daily life; and treatment practices. Out of 128 participants, 67 were in the (former) scabies group and had a mean age of 32.3 ± 15.6 years. Overall scabies group participants less often indicated a factor to predispose to scabies than community controls; only 'family/friends contacts' was more often mentioned in the scabies group. Scabies causation was attributed to poor hygiene, traditional beliefs, heredity and drinking water. Individuals with scabies delay care seeking (median time from symptom onset to visiting the health centre was 21 [14 - 30] days) and this delay is enhanced by their beliefs (like witchcraft and curses) and a perception of limited disease severity. Compared to past scabies participants in the dermatology clinic, participants with past scabies in the community tended to have a longer delay (median [IQR] 30 [14-48.8] vs 14 [9.5-30] days, p = 0.002). Scabies was associated with health consequences, stigma, and loss of productivity.

CONCLUSION/SIGNIFICANCE

Early diagnosis and effective treatment of scabies can lead to persons less frequently associating scabies with witchcraft and/ or curses. There is the need to enhance health education to promote early care seeking, enhance knowledge of communities on impact and dispel negative perceptions about scabies in Ghana.

[Translated article] Epidemic Scabies: New Treatment Challenges in an Ancient Disease

Scabies which is among the most prevalent diseases worldwide, is becoming more frequent in Spain. The problems of this epidemic can be explained by several factors: improper application or prescription of treatments, resistance or reduced sensitivity to topical treatments, and poor understanding of the parasite and contagion. We require a new evidence-based approach to therapy that takes these problems into consideration. If symptoms persist after proper treatment, it is important to identify the reason for failure and standardize our approach. In refractory cases, the prescriber should prioritize oral medication, indicate a higher dose, combine treatments, or evaluate the use of off-label treatments in certain populations. The availability of new medications, such as spinosad or, especially, moxidectin, offer hope for bringing this disease under control.

Pruritic papules and nodules as sign of persistent scabies infestation despite treatment according to current guidelines evidence for treatment resistance to ivermectin, benzylbenzoat and permethrin proven by videomicroscopy

Scabies infestation is a growing public health issue due to its world wide increase of incidence. The objective of this study was to proof treatment resistance towards treatment, which was applied according to international guidelines. This is a controversial issue since treatment failures were believed to be due to false application oft he treatment. Here, we proof fort he first time this treatment resistance by videomicroscopic evaluation. Additionally an escalation therapy is described, which led to an effective treatment.

Comparison of topical benzyl benzoate vs. oral ivermectin in treating scabies: A randomized study

BACKGROUND

Scabies is an itchy, parasitic infection of the skin. Recent reports indicate there is a decreasing efficacy of the standard treatment of choice, topical 5% permethrin cream.

OBJECTIVE

To evaluate the comparative efficacy, safety and tolerability of topical benzyl benzoate (BB) with oral ivermectin in the treatment of scabies.

METHODS

Patients with dermoscopy-verified scabies visiting the dermatologic outpatient clinic were assessed for enrolment in the study. In total, 224 patients were enrolled and sequentially randomized into two equally sized groups. Group A received topical 25% or 10% BB for the daily use over a period of three consecutive days, group B received oral ivermectin (200 μg/kg body weight) twice, 1 week apart. Treatment outcome was evaluated by dermoscopy at a 3-week follow-up visit.

RESULTS

Treatment resulted in a cure rate of 87% in group A and 86% in group B. After initial therapy failure in group A, six out of eight patients showed treatment response upon repeated application of BB, five of five when retreated with ivermectin and two of two with BB plus ivermectin, respectively. In group B, successful retreatment was observed in three out of three patients with ivermectin, two of two patients with BB and 11 of 11 patients with the combination of BB plus ivermectin, respectively. Tolerability and safety profile of oral ivermectin was excellent, while BB produced short burning sensations in 14%.

CONCLUSION

Topical BB and oral ivermectin have shown comparable good therapeutic efficacy. Therefore, both agents constitute an adequate first-line therapy in the treatment of scabies. A combination of both agents may be considered in recalcitrant and extensively infested cases, additionally to crusted scabies.

An Uncommon and Severe Clinical Case of Sarcoptes scabiei Infestation in a Cat

The burrowing mite Sarcoptes scabiei causes sarcoptic mange in dogs and other mammals, including humans. Despite S. scabiei infests several animals, little is known about the epidemiology, clinical features, and treatment of sarcoptic mange in cats. A few reports have shown that clinical signs of S. scabiei infestation in cats may vary from non-pruritic crusted lesions to itchy and mild lesions, while severe signs are very infrequent. The present report describes a severe case of S. scabiei infestation in a stray cat from Italy, characterized by bilateral alopecia, diffuse and multifocal hyperpigmented, crusted, erythematous, scaled, and exfoliated lesions. The cat was FIV-positive and also infected by the cestode Dipylidium caninum. After treatment with a broad-spectrum parasiticide and an antibiotic, the cat showed an almost complete clinical recovery in 4 weeks. Unfortunately, no further clinical examinations were performed due to the lack of compliance of the owner and to the death of the cat for causes unrelated to sarcoptic mange. This clinical case indicates that under certain circumstances, S. scabiei can reproduce and cause severe clinical signs in cats which are usually considered non-permissive hosts for this mite, and in which the disease is usually self-limiting. Clinic-pathological, epidemiological, and zoonotic implications are discussed.

Facilitations in the Clinical Diagnosis of Human Scabies through the Use of Ultraviolet Light (UV-Scab Scanning): A Case-Series Study

BACKGROUND

To confirm the suspicion of scabies, dermatologists have one pathognomonic sign, "the tunnel" through which Sarcoptes scabiei digs into the epidermis. Light microscopy is considered the most reliable procedure, but it is time-consuming and operator-dependent. Recently, dermoscopy has greatly improved the chances of recognizing mite in situ, but it is still linked to the examiner's experience and to the magnification capability of the device used.

METHODS

This article, based on a case-series study, describes a novel diagnostic path, which uses an ultraviolet LED source at 365 nm and a digital camera for the evaluation of lesions that raise the suspicion of scabies.

RESULTS

The gallery emits a naked-eye-visible wavy bluish-white linear luminescence, better than that of any standard lighting. UVA light is also able to identify Sarcoptes scabiei as a white or green point-shaped area. This sign can only be appreciated by enlarging its picture to full frame on a common PC monitor.

CONCLUSIONS

Ultraviolet light (365 nm) seems to offer help in the diagnosis of scabies because it saves time compared with light microscopy and because it does not require contact with the patient's skin, as in dermoscopy. Although examiner experience remains an important factor, it is easily compensated by procedural simplicity, the cost of the devices and, especially, by the clarity of the results, even in non-specific lesions.

Sesquiterpenes and monoterpenes from different varieties of guava leaf essential oils and their antioxidant potential

Despite that Sri Lanka is a biodiversity hotspot with numerous guava varieties (Psidium guajava L.), no adequate scientific research has been reported on leaf essential oil (EO) composition based on varieties and its pharmacological properties, namely antioxidant properties. Therefore, this study focused to evaluate the chemical compositions and antioxidative capacity of EOs isolated from leaves of seven guava varieties grown in Sri Lanka, including apple-guava (P. pomiferum , PGA), common-guava (P. guaja v a , PGCG), two wild-guava; cultivar of P. guajava (PGG) and a cultivar of P. guineense (PGE), two introduced varieties of P. guajava (PGK and PGP), and one introduced variety of P. guineense (PGC). The EOs were isolated using hydro-distillation and the chemical compositions were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS) technique, and the compounds that showed greater than 90% matching value were considered for characterization. The yields of EOs ranged from 0.02-0.26% (w/w) where PGE produced the greatest amount. About sixty-eight chemical compounds were identified from seven varieties and Sesquiterpenes were found to be the most abundant in the PGCG, PGG, PGE, and PGA varieties, whereas monoterpenes were found to be the most abundant in PGK, PGP, and PGC varieties. The sesquiterpenes, Nerolidol (70.0-7.9%), (-)-Globulol (21.0-7.0%), and Caryophyllene (20.4-1.4%) and monoterpenes, D-Limonene (30.3-14.1 %) were found as the major compounds of all studied guava varieties. Twenty-eight compounds were identified for the first time in guava EOs, including Cadinadiene-1,4, Benzylacetaldehyde, and Epiglobulol. The antioxidant efficacy of EOs varied from 329.56 ± 2.01 to 85.70 ± 2.01 μL Trolox Eq/L, where PGE showed the highest antioxidative potential. Ultimately, the chemical constituents and antioxidant capacity of isolated EOs varied with the variety, with EO from PGE leaves exerting an amazing antioxidant capacity compared to the others and being rich in Nerolidol. The findings of this study fill the gap in the literature on chemical constituents in the EO of guava leaves, and also it will open the avenue to discover novel potential compounds with outstanding pharmacological activities from guava leaves.

Comparison of sulfur ointment and permethrin treatments in scabies

Scabies is a contagious, parasitic skin disease that adversely affects the quality of life and, can cause systemic complications if it is not properly treated. Sulfur ointment and permethrin cream are among the most used topical agents in the treatment of scabies. In this study, we aimed to compare the efficacy of sulfur ointment and permethrin cream in the treatment of scabies. In this single-center study, patients who were diagnosed with scabies in the dermatology outpatient clinics of Karabuk University Training and Research Hospital between April, 2021 and September, 2021 were investigated retrospectively. Age, gender, date of diagnosis, topical agent used for scabies treatment, and response to the treatment at the control examination in the second week were recorded. The patients were divided into two groups those receiving 5% permethrin cream or 10% sulfur ointment, and the treatment efficacy of both agents was compared. This study showed that 10% sulfur ointment was significantly more effective in treating scabies than 5% permethrin cream (p < 0.001). Moreover, younger patients with scabies responded better to both treatments. 10% Sulfur ointment can be considered a safe and effective topical option in the treatment of scabies. The resistance to 5% permethrin cream, which is the most commonly used agent for scabies, can be a concern as an unexpected low success rate was obtained in this study.