Eliminate all risks: A call to reexamine the link between canine scabies and rheumatic heart disease.

Rheumatic heart disease (RHD) and acute rheumatic fever (ARF) disproportionately affect individuals in low-resource settings. ARF is attributed to an immune response to Group A Streptococcus (GAS) following GAS pharyngitis and potentially GAS impetigo in which infection can be initiated by scabies infestation. The burden of ARF and RHD in Aboriginal and Torres Strait Islander people in Australia is among the highest globally. Following recent calls to include dog management programs in ARF and RHD prevention programs, we believe it is timely to assess the evidence for this, particularly since previous recommendations excluded resources to prevent zoonotic canine scabies. While phylogenetic analyses have suggested that the Sarcoptes mite is host specific, they have differed in interpretation of the strength of their findings regarding species cross-over and the need for canine scabies control to prevent human itch. Given that there is also indication from case reports that canine scabies leads to human itch, we propose that further investigation of the potential burden of zoonotic canine scabies and intervention trials of canine scabies prevention on the incidence of impetigo are warranted. Considering the devastating impacts of ARF and RHD, evidence is required to support policy to eliminate all risk factors.

Non-specific effects of inactivated Mycobacterium bovis oral and parenteral treatment in a rabbit scabies model.

Tuberculosis BCG vaccination induced non-specific protective effects in humans led to postulate the concept of trained immunity (TRAIM) as an innate type of immune mechanism that triggered by a pathogen, protects against others. Killed vaccines have been considered not to be effective. However, field efficacy of a commercial vaccine against paratuberculosis, as well as of a recently developed M. bovis heat-inactivated vaccine (HIMB) prompted to test whether it could also induce TRAIM. To this, we used a sarcoptic mange rabbit model. Twenty-four weaned rabbits were treated orally or subcutaneously with a suspension of either HIMB (107 UFC) or placebo. Eighty-four days later the animals were challenged with approximately 5000 S. scabiei mites on the left hind limb. Skin lesion extension was measured every 2 weeks until 92 days post-infection (dpi). Two animals were killed at 77 dpi because of extensive skin damage. The rest were euthanized and necropsied and the lesion area and the mite burden per squared cm were estimated. Specific humoral immune responses to S. scabiei and to M. bovis were investigated with the corresponding specific ELISA tests. Subcutaneously and orally HIMB vaccinated animals compared with placebo showed reduced lesion scores (up to 74% and 62%, respectively) and mite counts (-170% and 39%, respectively). This, together with a significant positive correlation (r = 0.6276, p = 0.0031) between tuberculosis-specific antibodies and mite count at 92 dpi supported the hypothesis of non-specific effects of killed mycobacterial vaccination. Further research is needed to better understand this mechanism to maximize cross protection.

A proposal to reduce the amount of permethrin entering wastewater resultant from topical use to treat scabies.

The incidence of scabies is rising in the last years. Subsequently, the use of pharmaceuticals to treat the disease has also increased. Treatment with topical permethrin is usually recommended as a first line agent. This substance is also an aquatic contaminant that is toxic for many non-target organisms, and has been included as a priority substance in the recently published proposal of the European Water Framework Directive. Current guidelines neglect the potential environmental impact of this drug, recommending that the cream should be applied head to toe and "washed off after 8-12 h". Recently, a wiping procedure before hand washing after application of the topical treatment resulted in a 66 % reduction of the amount of diclofenac released in wastewater. The authors suggested that this method could be explored for other topical treatments. In the case of scabiosis, a protocol implicating the whole body needs to be designed. The absorption of topical permethrin is low. Considering the growing incidence of scabies, the amount of the pyrethroid reaching the environment may also be increasing. Therefore, we believe that applying the wiping procedure to the case of topical permethrin deserves consideration. Other measures to minimize the amount of permethrin residues reaching wastewater by washing clothes and bed linen such as wearing single-use pijamas should also be explored. In conclusion, we need to apply a One Health approach in the treatment with scabies, without neglecting the environmental impact of pharmaceuticals. It is not rational to forget drugs once they go down the drain.

Awareness and knowledge of scabies and ringworm among parents of school-age children in Calabar, Cross River State, Nigeria: Implications for prevention of superficial skin infestations.

Context: Risk factors for the persistence of superficial skin infestations are prevalent in humid tropical environments, which are favorable for breeding of the causative vector mite Sarcoptes scabiei (ectoparasite) and dermatophyte fungi. Aim: This study aimed at assessing the awareness and knowledge of childhood scabies and ringworm infestations among parents in Calabar, a highly humid rainforest tropical environment. Settings and Design: Cross-sectional study design and systematic random sampling were used to recruit school-age children in selected primary schools in Calabar. Materials and Methods: Researcher-driven administration of a structured questionnaire was conducted to obtain quantitative data from parents of recruited children. Statistical Analysis Used: : Chi-square was used to assess factors associated with ever hearing or seeing scabies and ringworm infestations. Statistical significance was set at P < 0.05. Results: One hundred and eighty-two (56.7%) and 218 (67.9%) of the respondents had heard of or seen scabies and ringworm infestation. Among respondents that were aware of scabies, 53.3% knew of the cause, 50.5% were aware of the risk factors while 68.1% and 78.0% knew their treatment and prevention, respectively; 98.6%, 60.6%, 76.6%, and 80.7% of respondents knew the cause, risk factors, treatment, and prevention of ringworm infestation, respectively. Fathers with at least secondary school literacy level and sharing beds were significantly associated with awareness of scabies. Conclusion: There is a suboptimal level of awareness and knowledge of two of the most common superficial skin infestations among parents of primary school children in the study setting. There is a need to redouble our effort at sensitization of parents toward improved awareness of these common infestations.

Résumé Contexte: Les facteurs de risque de persistance des infestations cutanées superficielles sont prévalents dans les environnements tropicaux humides, favorables à la reproduction du vecteur responsable, la gale Sarcoptes scabiei (ectoparasite), et des champignons dermatophytes. Objectif : Cette étude visait à évaluer la sensibilisation et les connaissances des parents de Calabar, un environnement tropical de forêt équatoriale très humide, concernant la gale et les infestations à la teigne chez les enfants. Cadre et conception : Une étude transversale et un échantillonnage systématique ont été utilisés pour recruter des enfants d'âge scolaire dans des écoles primaires sélectionnées à Calabar. Méthodes et matériel: Une administration dirigée par le chercheur d'un questionnaire structuré a été réalisée pour obtenir des données quantitatives auprès des parents des enfants recrutés. Analyse statistique utilisée: Le test du chi carré a été utilisé pour évaluer les facteurs associés à la connaissance de la gale et des infestations à la teigne. La signification statistique a été fixée à P < 0,05. Résultats: Cent quatre-vingt-deux (56,7 %) et 218 (67,9 %) des répondants avaient entendu parler ou vu une infestation de gale et de teigne. Parmi les répondants qui étaient au courant de la gale, 53,3 % connaissaient la cause, 50,5 % étaient conscients des facteurs de risque, tandis que 68,1 % et 78,0 % connaissaient respectivement leur traitement et leur prévention. De même, 98,6 %, 60,6 %, 76,6 % et 80,7 % des répondants connaissaient respectivement la cause, les facteurs de risque, le traitement et la prévention de l'infestation à la teigne. Les pères ayant au moins un niveau d'alphabétisation au niveau secondaire et partageant des lits étaient significativement associés à la connaissance de la gale. Conclusion: Il existe un niveau sous-optimal de sensibilisation et de connaissance de deux des infestations cutanées superficielles les plus courantes parmi les parents d'enfants d'école primaire dans le cadre de l'étude. Il est nécessaire de redoubler d'efforts pour sensibiliser les parents afin d'améliorer la connaissance de ces infestations courantes. Mots-clés: Infestations cutanées, gale, teigne, connaissance, parents, enfants d'âge scolaire, Nigeria.

No secondary impact of ivermectin mass drug administration for onchocerciasis elimination on the prevalence of scabies in northwestern Ethiopia.

BACKGROUND: Mass drug administration (MDA) is among the five major strategies that are currently in use to control, eliminate or eradicate Neglected Tropical Diseases (NTDs). Optimising MDA to control multiple NTDs maximises impact. The objective of this study is to estimate the secondary impact of ivermectin MDA for onchocerciasis on the prevalence of scabies. METHODS: This quasi-experimental study was conducted in Ayu Guagusa district, northwestern Ethiopia. Scabies prevalence was estimated in surveys before the MDA, at 6 and 12 months afterwards. The sample size was 1437 people from a panel of 381 randomly selected study households. Multistage sampling was employed in randomly selecting six kebeles (the lowest administrative unit) with respective gotes (small villages) and households. All members of the selected households were invited to participate in the study and participants who were available in all three surveys formed a cohort. RESULTS: Scabies prevalence was similar prior to the MDA (13.4%, 95% CI 11.7 to 15.2%) and 6 months after (11.7%, 95% CI 10.1 to 13.2%) but was substantially greater at 12 months (22.1%, 95% CI 20.1 to 24.1%). The 6-month incidence and disappearance rates were 10.8% (95% CI 8.8 to 13.2%) and 82.6% (95% CI 75.0 to 88.6%), respectively. CONCLUSIONS: Ivermectin MDA for onchocerciasis was not observed to have a secondary impact on the prevalence of scabies over the follow-up period of 12 months.

Investigation of Malaria, Leishmaniasis, and Scabies Risk after Earthquakes and Recommendations for Prevention.

This study examines the risk of malaria, leishmaniasis, and scabies following earthquakes in southeastern Türkiye. The focus is on the impact on the local population and Syrian immigrants. Recommendations for prevention include vector control measures such as indoor residual spraying and distribution of insecticidal nets. Surveillance and early detection through rapid diagnostic tests and active case finding are important. Public awareness campaigns and community engagement are crucial for promoting protective measures. Strengthening healthcare infrastructure, providing essential supplies, and capacity building is essential. For leishmaniasis, early detection and treatment, vector control, health education, and community engagement are vital. Scabies outbreaks affect the socioeconomically depressed local population and Syrian immigrants. Early detection, treatment, contact tracing, health education, hygiene promotion, and improved living conditions are necessary. Implementing these interventions and strategies can effectively prevent, control, and manage these diseases. Tailoring approaches to the specific context and needs of affected communities is crucial. By addressing these challenges, we can protect the health and well-being of the affected population.

Living in a large family and low daily water consumption substantially expose for human scabies in rural Ethiopia: a matched analysis.

BACKGROUND: Scabies has been added to the neglected tropical diseases portfolio for large-scale disease control action since 2017 and is part of the WHO roadmap for NTDs 2021-2030, targeted at ending the neglect to achieve the sustainable development goals. Previous studies have not fitted matched analysis to identify predictors of scabies infestation in Ethiopia. Information is also scarce about predictors of scabies infestation in this area. Therefore, this study aimed to identify predictors of scabies infestation in rural Aneded District, northwest Ethiopia. METHODS: A community-based matched case-control study involving 183 cases and 549 controls was undertaken from March 1 to May 31, 2021, in rural Aneded District. A two-stage sampling technique with a house-to-house census for the screening of scabies cases was employed. A structured questionnaire with questions on sociodemographics, behavior, water supply, sanitation, and hygiene, and delivery of scabies-specific interventions was used. Pretesting, training of data collectors and supervisors, and supervision were applied to keep the data quality. A multivariable conditional logistic regression model was fitted to identify predictors of scabies. RESULTS: Unmarried individuals or those in separated families (adjusted matched odds ratio (AmOR = 2.71; 95% CI 1.30-5.65); those unable to read and write or in illiterate families (AmOR = 5.10; 95% CI 1.81-14.36); those in large families (AmOR = 6.67; 95% CI 2.83-15.73); households that had longer travel times for water collection (AmOR = 2.27; 95% CI 1.08-4.76); those that had low daily water consumption (AmOR = 6.69; 95% CI 2.91-15.37); households that disposed of solid wastes in open fields (AmOR = 5.60; 95% CI 2.53-12.40); and households that did not receive scabies-specific interventions (AmOR = 2.98; 95% CI 1.39-6.39) had increased odds of scabies. CONCLUSIONS: Being unmarried, illiteracy, large family, long travel time for water collection, low daily water consumption, open dumping of solid wastes, and inaccessibility of scabies-specific interventions are predictors of scabies. This information is instrumental for redesigning improved scabies-specific interventions that consider educational status, marital status, family size, water collection time, daily water consumption, solid waste disposal, and equity and optimization in delivering existing interventions in rural Ethiopia.

Modelling mass drug administration strategies for reducing scabies burden in Monrovia, Liberia.

Scabies is a parasitic infestation with high global burden. Mass drug administrations (MDAs) are recommended for communities with a scabies prevalence of >10%. Quantitative analyses are needed to demonstrate the likely effectiveness of MDA recommendations. In this study, we developed an agent-based model of scabies transmission calibrated to demographic and epidemiological data from Monrovia. We used this model to compare the effectiveness of MDA scenarios for achieving scabies elimination and reducing scabies burden, as measured by time until recrudescence following delivery of an MDA and disability-adjusted-life-years (DALYs) averted. Our model showed that three rounds of MDA delivered at six-month intervals and reaching 80% of the population could reduce prevalence below 2% for three years following the final round, before recrudescence. When MDAs were followed by increased treatment uptake, prevalence was maintained below 2% indefinitely. Increasing the number of and coverage of MDA rounds increased the probability of achieving elimination and the number of DALYs averted. Our results suggest that acute reduction of scabies prevalence by MDA can support a transition to improved treatment access. This study demonstrates how modelling can be used to estimate the expected impact of MDAs by projecting future epidemiological dynamics and health gains under alternative scenarios.

One versus two doses of ivermectin-based mass drug administration for the control of scabies: A cluster randomised non-inferiority trial.

BACKGROUND: Mass drug administration (MDA) based on two doses of ivermectin, one week apart, substantially reduces prevalence of both scabies and impetigo. The Regimens of Ivermectin for Scabies Elimination (RISE) trial assessed whether one-dose ivermectin-based MDA would be as effective. METHODS: RISE was a cluster-randomised trial in Solomon Islands. We assigned 20 villages in a 1:1 ratio to one- or two-dose ivermectin-based MDA. We planned to test whether the impact of one dose on scabies prevalence at 12 and 24 months was non-inferior to two, at a 5% non-inferiority margin. RESULTS: We deferred endpoint assessment to 21 months due to COVID-19. We enrolled 5239 participants in 20 villages at baseline and 3369 at 21 months from an estimated population of 5500. At baseline scabies prevalence was similar in the two arms (one-dose 17·2%; two-dose 13·2%). At 21 months, there was no reduction in scabies prevalence (one-dose 18·7%; two-dose 13·4%), and the confidence interval around the difference included values substantially greater than 5%. There was however a reduction in prevalence among those who had been present at the baseline assessment (one-dose 15·9%; two-dose 10·8%). Additionally, we found a reduction in both scabies severity and impetigo prevalence in both arms, to a similar degree. CONCLUSIONS: There was no indication of an overall decline in scabies prevalence in either arm. The reduction in scabies prevalence in those present at baseline suggests that the unexpectedly high influx of people into the trial villages, likely related to the COVID-19 pandemic, may have compromised the effectiveness of the MDA. Despite the lack of effect there are important lessons to be learnt from this trial about conducting MDA for scabies in high prevalence settings. TRIAL REGISTRATION: Registered with Australian New Zealand Clinical Trials Registry ACTRN12618001086257.

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.

Vaccination with a cocktail vaccine elicits significant protection against Sarcoptes scabiei in rabbits, whereas the multi-epitope vaccine offers limited protection.

Sarcoptes scabiei cause scabies in humans or sarcoptic mange in animals. Currently, information regarding vaccines against S. scabiei is limited and no commercial vaccine is available. In present study, we expressed and mixed recombinant S. scabiei serpin (rSs-serpin), recombinant S. scabiei chitinase-like protein-5 [rSs-CLP5] and -12 [rSs-CLP12] as a cocktail vaccine (three proteins mixed), and also a multi-epitope protein derived from these three S. scabiei genes was expressed as a vaccine candidate to evaluate the effects of two vaccine strategies. Four test groups (n = 12 per group) and a control group (n = 12 per group) were involved in this vaccination trial. The results showed that 91.67% (11/12) and 83.33% (10/12) of rabbits exhibited no detectable skin lesions from S. scabiei infestation in cocktail vaccine groups, whereas two multi-epitope groups produced only a few rabbits (5/12, 6/12) having no detectable skin lesions. Four test groups displayed significant increases in specific IgG antibodies (Abs) and total IgE Abs after immunized with recombinant proteins. Taken together, our data demonstrated a mixture of rSs-serpin, rSs-CLP5 and rSs-CLP12 was a promising vaccine candidate that induced robust immune protection and could significantly decrease mite populations to reduce the direct transmission between rabbits. However, vaccination with the multi-epitope protein showed limited protection in rabbits.

A scabies outbreak in an inpatient rehabilitation setting.

BACKGROUND: Scabies is a skin infection transmitted by close person-to-person contact. Crusted scabies is a more severe type which is more contagious. Delayed diagnosis of scabies could lead to an outbreak. METHODS: The outbreak occurred at a 435-bed academic medical center with 76 inpatient rehabilitation beds. The index patient was incarcerated and admitted to our hospital in February 2022. The patient developed crusted scabies after steroids treatment. RESULTS: The patient was treated with oral ivermectin (200 mcg/kg, maximum dose 15 mg) and topical permethrin 5%. All units were followed for 6 weeks since diagnosis of the index patient. A total of 46 healthcare workers (20 nurses and 26 physical therapists) were exposed. Twenty-nine presented symptoms and were treated with ivermectin and permethrin or only ivermectin. No physicians, other patients, or prison guards were affected. There was no secondary household transmission of those exposed healthcare workers. CONCLUSIONS: Scabies is highly contagious in high-risk patients. Early diagnosis and effective infection control are of vital importance.

Effects of ivermectin mass drug administration for malaria vector control on ectoparasites and soil-transmitted helminths: a cluster randomized trial.

OBJECTIVES: Ivermectin, used to control several neglected tropical diseases, may also reduce malaria transmission. Mass drug administration (MDA) for malaria control therefore might have off-target impacts on neglected tropical diseases. METHODS: In The Gambia, nested in a trial of ivermectin MDA, cross-sectional surveys measuring ectoparasites and soil-transmitted helminths in children aged 3 to 14 years took place in June and November 2019 and in November 2021. RESULTS: After MDA, scabies prevalence was 41.2% (237/576) in the control and 38.2% (182/476) in the intervention arm (odds ratio [OR] 0.89 (95% confidence interval [CI] 0 67-1.2), P-value = 0.471) but by 2021, had rebounded to 38.8% (180/464) in the control and 53.2% (245/458) in the intervention arm. After MDA, prevalence of Strongyloides stercoralis was 16.8% (87/518) in the control and 9.1% (40/440) in the intervention arm (OR 0.4 (95% CI 0.16-0.94), P-value = 0.039). In 2021, it was 9.2% (38/413) in the control and 11.3% (45/399) in the intervention arm (OR 1.31 (95% CI 0.74-2.28), P-value = 0.35). CONCLUSION: Scabies prevalence was similar between the two study arms. S. stercoralis prevalence was reduced. However, this effect did not last long: the prevalence 2 years after MDA was similar between study arms.

Ivermectin mass drug administration for onchocerciasis elimination: can it reduce the prevalence of scabies in Ethiopia?

INTRODUCTION: While ivermectin mass drug administration (MDA) has been implemented since long for onchocerciasis elimination, there is doubt whether this would also be effective for scabies control. If effective, this would allow integration of both programs. We compared scabies prevalence in districts implementing ivermectin MDA for the onchocerciasis elimination program and those not implementing the intervention in Amhara region, Ethiopia. METHODOLOGY: We conducted a cross-sectional study comparing the scabies prevalence in 14 districts implementing ivermectin MDA for onchocerciasis elimination program between 2013-2018 and in 28 districts without this intervention in Amhara region Ethiopia. We used 2018 scabies survey data to determine scabies prevalence. All individuals screened for scabies during the survey were included. We collected data on risk factors from the districts database and annual reports. Multivariate linear regression analysis was used to account for potential confounding factors. RESULTS: We included data on 4,319,064 subjects across 42 districts. Except the differences in temperature and population density, districts in both groups were comparable. A total of 371,780 scabies cases were detected in the 2018 survey. The median scabies prevalence was 6% (IQR 2.6-11.9) in the intervention districts and 5.2% (1.8-10.4) in the control districts (p-value 0.77). In adjusted analysis, the difference remained statistically non-significant (coefficient 0.37 (95% confidence interval (-0.93-1.67); p-value 0.554). CONCLUSIONS: The implementation of ivermectin MDA for onchocerciasis control was not associated with reduced scabies prevalence. Consequently, standard scabies MDA should be deployed for scabies control.

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.

Decreases in scabies and lice cases among the pediatric and adult populations during COVID-19.

The influence of the nationwide lockdown orders during the COVID-19 pandemic on the transmission of scabies and lice remains unknown. We conducted a cross-sectional study utilizing UNC patient registry i2b2 to investigate monthly cases and prescriptions for scabies and lice in adult and pediatric patients in North Carolina. There were significant decreases in the cases and prescriptions for scabies and lice in the pediatric and adult populations. These results provide early insights on how COVID-19 pandemic lockdown orders affected the prevalence of these two conditions and suggest that physical distancing measures reduce transmission of these parasitic conditions.