A systematic review of scabies transmission models and data to evaluate the cost-effectiveness of scabies interventions

Acceptability of a nationwide scabies mass drug administration (MDA) program in Fiji: a qualitative interview-based study

Background

Fiji has among the highest global reported prevalence of scabies. Mass drug administration (MDA) has been identified as a potentially effective strategy to control scabies, but acceptability of MDA from the perspectives of people receiving and delivering scabies MDA programs remains underexplored in Fiji and globally.

Methods

A qualitative study was conducted after completion of the national MDA campaign. Participants included 44 community members and 12 key informants across the Central and Western Divisions of Fiji. Semi-structured face-to-face and virtual interviews were conducted in August and September 2023. An interpretive research approach was adopted, and data were analysed using deductive and inductive techniques.

Findings

We identified several barriers and facilitators to scabies MDA acceptability. Facilitators included prior experiences of scabies and knowledge of the potential health benefit of MDA, community attitudes to MDA and neighbours' adherence practices, endorsement of MDA by community leaders, community consultation and exposure to community sensitisation, and involvement of local key informants during planning and implementation. Barriers included a lack of trust in MDA campaigns, religious beliefs, limited reach of community sensitisation, and challenges to implementing MDA in urban locations.

Interpretation

This is the first qualitative study documenting acceptability of a nationwide scabies-MDA globally. It identified diverse socio-structural factors that influenced MDA implementation and acceptability. Future MDA programs could benefit from widespread community sensitisation, tailored approaches to urban and rural MDA design and delivery, and the inclusion of communities in the co-design and implementation of MDA programs.

Funding

The National Health and Medical Research Council (NHMRC) investigator grant-LR and the Macquarie Group Foundation 50th Celebration Awards-AS.

An unusual case of crusted scabies in an immunocompetent adult: A case report

Key Clinical Message

Although rare, crusted scabies can affect immunocompetent individuals with no identifiable risk factors. A high index of suspicion, regardless of an individual's immunological status or absence of traditional risk factors, should be maintained by health professionals to facilitate prompt referral to a dermatologist.

Abstract

Crusted scabies is an uncommon variant of human scabies characterized by extensive crusted and scaly hyperkeratotic papules, and plaques resulting from profound proliferation of mites in the skin. It is highly contagious and typically occurs in immunocompromised individuals. Reports of cases in healthy adults are rare. It is often resistant to routine treatment. We report a case of a 30-year-old immunocompetent male who presented to us with an extensive pruritic papular rash that started in the inter-digital web spaces of his hands. Within 3 months from onset, the lesions progressed, and became hyperkeratotic, scaly, non-pruritic, spreading to involve his entire body (sparing his face only). Crusty scabies was eventually diagnosed and treated by a dermatologist after months of misdiagnosis at peripheral facilities. Although rare, crusted scabies can affect immunocompetent individuals. A high index of suspicion is required, regardless of immunological status. Among immunocompetent individuals, a thorough search for traditional risk factors is imperative.

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.

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.

Norwegian scabies in human immunodeficiency virus and tuberculosis-infected child: A case report

Norwegian scabies is a rare scabies with the manifestation of thick crusts of the extremities of the skin that contain eggs and mites. Several conditions in which scabies infection is easily transmitted include immunocompromised, home nursing, and severe neurological disorder. The aim of this case report was to present a thorough analysis of a comprehensive resource for the management of Norwegian scabies patients, with a specific focus on individuals who also have HIV or other immunocompromising diseases. A 1-year-and-7-month-old boy was presented to the hospital with a chief complaint of a thick crust that he had experienced for four months. It began as a red papule in the lower extremity, then crusted and spread to the whole body. The patient kept scratching due to itching, had a recurrent fever and diarrhea for three months, and cough for one month. The patient was diagnosed with human immunodeficiency virus (HIV) and pulmonary tuberculosis at three months, suspected to get the infection from the parents. Sarcoptes scabiei was found from microscopy examination of skin scraping. The patient received holistic treatment, including antiretroviral drugs, antituberculosis medication, scabies treatment, and malnutrition treatment. Appropriate scabies treatment aimed at peeling crusted skin, relieving itching, and increasing the patient ability to use the extremities. Comorbidity conditions caused by HIV and pulmonary tuberculosis should also be treated to optimize the outcome. The patient was discharged in good condition with sanitation education and regular follow-up at the outpatient clinic. This case highlights that Sarcoptes scabiei infestation may be a clue to an immunocompromised condition. Holistic therapy aiming to cure underlying infection, infestation and underlying nutrition and psychosocial problems must be addressed to fully cure this high-burden case.

Crusted Hyperkeratotic Scabies: A Case Report

Crusted scabies is a rare form of classic scabies characterized by severe symptoms, mainly observed in immunosuppressed patients. This disease has been associated with a variety of health problems, such as delayed diagnosis, infection risk, and high mortality, mainly from sepsis. We report the case of a patient with hyperkeratotic scabies in the context of immunosuppression associated with malnutrition and the use of topical corticosteroids. Ivermectin is critical for successfully treating crusted scabies. However, a higher cure rate has been reported with the combination of oral ivermectin and topical permethrin. In our study, we chose to use a plan suitable for grade two scabies, resulting in a subtotal regression of the lesions. Crusted scabies is a highly contagious parasitic cutaneous disease, and there are few reports in the national and international literature. It is necessary to suspect this presentation form in order to establish a timely diagnosis and detect and treat associated comorbidities.

Prevalence of scabies and associated factors among children aged 5-14 years in Meta Robi District, Ethiopia

BACKGROUND

Scabies is a public health problem that affects children and elders predominantly. Its burden is higher in resource-poor settings, and scabies has a significant impact on the long-term health of children. In Ethiopia, there is limited information about scabies in children. Therefore, the purpose of this study was to determine the prevalence of scabies and its associated factors among children aged 5-14 years in Meta Robi District, Ethiopia.

METHODS

A community-based cross-sectional study design using a multistage sampling technique was used to collect data from 457 participants by systematic random sampling. Scabies was diagnosed based on the clinical criteria set by the International Alliance for the Control of Scabies (IACS, 2020).

FINDINGS

The prevalence of scabies among children aged 5-14 years old was 19.26% (95%CI: 17.20-22.52). In addition, over half (54.6%) of identified cases of scabies were of moderate severity. Factors like families' low income (aOR = 2.72; 95%CI: 1.32-5.59), being a male child (aOR = 1.96, 95%CI: 1.61-4.01), using only water for hand washing (aOR = 2.01, 95%CI: 1.84-4.79), having a contact history of scabies/skin lesions (aOR = 4.15, 95%CI: 2.02-13.67), and sharing sleeping beds (aOR = 6.33, 95%CI: 2.09-19.13) were significantly associated with scabies.

CONCLUSION

The study highlights a high prevalence of scabies among children aged 5-14 years in the district. Provision of adequate health education for the community and children about the scabies and delivering mass drug administration to the district is suggested.

Crusted Scabies, a Neglected Tropical Disease: Case Series and Literature Review

Crusted scabies is a rare form of scabies that presents with more severe symptoms than those of classic scabies. It is characterized by large crusted lesions, extensive scales, thick hyperkeratosis, and contains a large number of highly contagious itch mites. Crusted scabies is more prevalent in immunocompromised, malnourished, and disabled individuals. This disease has been linked to a variety of health problems, including delayed diagnosis, infection risk, and high mortality, mainly from sepsis, and it has the potential to cause an outbreak due to its hyper-infestation, which makes it highly infectious. This article reports three cases of crusted scabies in North Sulawesi, Indonesia. Recent updates and a comprehensive review of the literature on the disease are also included, emphasizing the critical importance of early diagnosis and effective medical management of patients, which are necessary to prevent the complications and spread in communities.

Health care cost of crusted scabies in Aboriginal communities in the Northern Territory, Australia

Background

Crusted scabies is a debilitating dermatological condition. Although still relatively rare in the urban areas of Australia, rates of crusted scabies in remote Aboriginal communities in the Northern Territory (NT) are reported to be among the highest in the world.

Objective

To estimate the health system costs associated with diagnosing, treating and managing crusted scabies.

Methods

A disease pathway model was developed to identify the major phases of managing crusted scabies. In recognition of the higher resource use required to treat more severe cases, the pathway differentiates between crusted scabies severity grades. The disease pathway model was populated with data from a clinical audit of 42 crusted scabies patients diagnosed in the Top-End of Australia’s Northern Territory between July 1, 2016 and May 1, 2018. These data were combined with standard Australian unit costs to calculate the expected costs per patient over a 12-month period, as well as the overall population cost for treating crusted scabies.

Findings

The expected health care cost per patient diagnosed with crusted scabies is $35,418 Australian dollars (AUD) (95% CI: $27,000 to $43,800), resulting in an overall cost of $1,558,392AUD (95% CI: $1,188,000 to $1,927,200) for managing all patients diagnosed in the Northern Territory in a given year (2018). By far, the biggest component of the health care costs falls on the hospital system.

Discussion

This is the first cost-of-illness analysis for treating crusted scabies. Such analysis will be of value to policy makers and researchers by informing future evaluations of crusted scabies prevention programs and resource allocation decisions. Further research is needed on the wider costs of crusted scabies including non-financial impacts such as the loss in quality of life as well as the burden of care and loss of well-being for patients, families and communities.

Crusted scabies is characterised by thick skin crusting and fissuring and can lead to serious secondary infections and death from complications. Rates of crusted scabies in remote Aboriginal communities in the Northern Territory (NT) are among the highest in the world. Efforts are on the way in Australia to prevent, if not eliminate, crusted scabies. We use data from a clinical audit of 42 patients diagnosed with crusted scabies in the Top-End of the NT to estimate the health system costs associated with diagnosing, treating and managing crusted scabies for patients and their households. This cost of illness study can provide a valuable starting point for policy makers and evaluators in estimating the potential economic impact of crusted scabies prevention programs on health care service use and costs.

Mass drug administration for the control of scabies: a systematic review and meta-analysis

BACKGROUND

Scabies is a neglected tropical disease of the skin that can lead to impetigo, serious secondary bacterial infections and immune-mediated diseases. Mass drug administration (MDA) has been reported in several studies to reduce the prevalence of scabies and impetigo. We aimed to assess the efficacy of MDA for scabies on scabies and impetigo.

METHODS

We conducted a systematic review and meta-analysis of reports on the impact of MDA on scabies and impetigo. We included randomised control trials and observational evaluations reported from January 1970 to April 2021 and involving human participants. We searched PubMed, Ovid Medline, Embase and Cochrane. We considered MDA as treatment intended for the whole population, regardless of individual infection status or symptoms. The main outcome assessed was the change in scabies and impetigo prevalence following MDA. This review is registered with PROSPERO (CRD42020169839).

RESULTS

We identified 1110 records, of which 11 met inclusion criteria for the review and 9 were deemed suitable for meta-analysis for scabies and four for impetigo. Most studies were in small populations. There was a high degree of heterogeneity between studies (I 2 value 96·19%). The overall relative reduction of the impact of MDA on scabies prevalence was 79%. The effect size was comparable for MDA based on ivermectin and permethrin. MDA for scabies also led to a reduction in impetigo prevalence with a relative reduction of 66%.

CONCLUSIONS

MDA for scabies is highly effective in reducing the prevalence of scabies and impetigo. Further research is needed to determine the durability of impact, and the effectiveness of MDA regimens in larger populations.

Sexually Transmitted Infections Treatment Guidelines, 2021

These guidelines for the treatment of persons who have or are at risk for sexually transmitted infections (STIs) were updated by CDC after consultation with professionals knowledgeable in the field of STIs who met in Atlanta, Georgia, June 11–14, 2019. The information in this report updates the 2015 guidelines. These guidelines discuss 1) updated recommendations for treatment of Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis; 2) addition of metronidazole to the recommended treatment regimen for pelvic inflammatory disease; 3) alternative treatment options for bacterial vaginosis; 4) management of Mycoplasma genitalium; 5) human papillomavirus vaccine recommendations and counseling messages; 6) expanded risk factors for syphilis testing among pregnant women; 7) one-time testing for hepatitis C infection; 8) evaluation of men who have sex with men after sexual assault; and 9) two-step testing for serologic diagnosis of genital herpes simplex virus. Physicians and other health care providers can use these guidelines to assist in prevention and treatment of STIs.

Risk factors associated with scabies infestation among primary schoolchildren in a low socio-economic area in southeast of Iran

Background

Scabies is a neglected tropical disease caused by the mite Sarcoptes scabiei that burrows under the skin. It is a major health problem in tropical areas, largely affecting children. Scabies is common and highly contagious and in schoolchildren spreads quite rapidly, due to overcrowding and close contact within the schools. This study aimed to determine the risk factors associated with scabies infestation among primary schoolchildren in Bashagard County, one of the low socio-economic areas in southeast of Iran.

Methods

To conduct this community-based, descriptive, and cross-sectional study, four primary schools were randomly selected in the Bashagard County. All students in these schools were selected and examined for scabies. Clinical examination and sociodemographic profile of students were assessed using a pre-tested structured questionnaire. Chi-square test, and binary logistic regression were used to analyse the factors associated with scabies infestation by SPSS version 21 software.

Results

Out of 480 studied schoolchildren, 15 cases of scabies with a prevalence of 3.1 % were observed. The frequency of infestation in males was 1.6 % and it was 4.7 % in females. Independent factors associated with a high risk of scabies infestation in unadjusted analysis were being student of grade 5–6 (cOR = 13.12, 95 % CI 2.92–58.89, p = 0.0001), low educational level of father (cOR = 4.37, 95 % CI 0.97–19.59, p = 0.036), low educational level of mother (cOR = 4.14, 95 % CI 1.92–18.57, p = 0.045), joblessness of father (cOR = 14.77, 95 % CI 4.97–43.89, p = 0.0001), employment of mother (cOR = 5.28, 95 % CI 1.38–20.16, p = 0.007), large family size (cOR = 3.34, 95 % CI 1.05–10.64, p = 0.031), use of shared articles (cOR = 33.37, 95 % CI 10.82–102.90, p = 0.0001), and absence of bathroom in the house (cOR = 11.77, 95 % CI 2.16–63.94, p = 0.0001).

Conclusions

Results of this study confirmed that scabies is still one of the most important health problems in the primary schools of the Bashagard County. Low socioeconomic status and personal hygiene of the schoolchildren were the most important factors influencing the prevalence of scabies. Improvement of socioeconomic conditions and implementation of appropriate educational programs and active surveillance system to quickly detect and treat scabies cases are necessary in order to reduce the prevalence of scabies in schoolchildren in this area.

Laboratory-based diagnosis of scabies: a review of the current status

Scabies is a neglected tropical disease (NTD) of the skin that is caused by the mite Sarcoptes scabiei. It is considered to be an important public health problem in many regions. The disease is at its most prevalent in low-resource countries where there are overcrowded living conditions coupled with poor hygiene. In some regions, mass drug administration using ivermectin is a key population-based approach to the control of scabies. Before starting a patient on specific treatment, confirming the diagnosis by accurate and rapid identification of the organism is critical. Different laboratory-based techniques for scabies have been developed in the last few decades. These include direct microscopy and histopathology. More recently, serological testing, dermoscopy and different molecular techniques have been developed as diagnostic methods for scabies. To date, none of these, apart from microscopy and dermoscopy, has been translated into routine clinical laboratory practice. A simple point-of-care or laboratory test would provide a rapid and confirmed diagnosis and early institution of effective treatment. In this review we present an update on the laboratory techniques currently in use for the identification of scabies.

Scabies: A comprehensive review and current perspectives

Human scabies is a contagious skin infestation caused by the parasitic mite Sarcoptes scabiei var. hominis. It is a common skin disease worldwide that occurs not only in the underprivileged sections of society but also in developed countries. In 2009, World Health Organization (WHO) recognized scabies as "neglected tropical disease (NTD)" or NTD thus emphasizing the need for community awareness and proper treatment strategies. This review attempts to summarize the varied clinical presentation of the disease and describes the advances in diagnosis and management including the ongoing search for novel agents to overcome the problems associated with conventional treatments. The literature research includes peer-reviewed articles (clinical trials or scientific reviews). Studies were identified by searching electronic databases (MEDLINE and PubMed) till February 2020 and reference lists of respective articles. Only articles published in English language were included.

Classic and Non-classic (Surrepticius) Scabies: Diagnostic and Treatment Considerations

The morphology of scabies, a mite infestation of worldwide proportion, is characterized by a variety of cutaneous lesions. Patients with classic scabies present with characteristic burrows often located on the web spaces of the fingers and toes. Scabies surrepticius refers to the non-classic atypical presentation of scabies; establishing the diagnosis of scabies in these individuals can be difficult. To facilitate the diagnosis of scabies, criteria have been proposed by the International Alliance for the Control of Scabies (IACS). These criteria are intended for scabies research; however, they can be utilized by clinicians to establish either a confirmed diagnosis, a clinical diagnosis or a suspected diagnosis of scabies. Visualization of mites, eggs or feces is necessary for a confirmed diagnosis of scabies. A clinical diagnosis can be established by observation of either genital lesions in men or burrows or classically distributed classical lesions in individuals with two historic features: pruritus and close contact with an individual who itches and has classically distributed classical scabetic lesions. The clinical features and management of a woman residing in an assisted living environment with a confirmed diagnosis of scabies and a man with a clinical diagnosis of scabies are described. The criteria for the suspected diagnosis of scabies require either one historic feature and typical lesions in a typical distribution or both historic features and the presence of atypical lesions or an atypical distribution of the skin lesions. Once the diagnosis of scabies is established, not only the patient but also close contacts should receive treatment with either a topical medication (such as permethrin 5% cream) or a systemic drug (ivermectin) or both. The number and frequency of treatments are variable; classic scabies typically is managed with a total of two treatments performed weekly to biweekly. Patients with crusted scabies usually require multiple topical and oral antiscabetic treatments in addition to topical keratolytic therapy. Bacterial impetiginization or infection (most commonly by Staphylococcus aureus or Streptococcus pyogenes) can complicate scabies infestation and potentially result in cellulitis, abscess, sepsis, rheumatic fever, rheumatic heart disease and post-streptococcal glomerulonephritis; therefore, in some patients, systemic antimicrobial therapy may be necessary in addition to scabies-directed treatment. In addition to systemic antihistamines, oral and/or topical corticosteroids may be used to provide symptomatic pruritus relief once the diagnosis of scabies has been established and mite-directed treatment has been initiated. The clinician should consider several potential causes (such as inadequate treatment, reinfection, mite resistance, delusions of parasitosis and the development of a new non-scabetic dermatosis) in scabies patients who fail to respond to treatment with a topical or oral scabicide therapy.