RESEARCH ARTICLE A facility and community-based assessment of scabies in rural Malawi Cristina Galván-Casas ID1,2,3*, Oriol Mitjá4,5,6, Sara Esteban7, Jacob Kafulafula8, Texon Phiri9, Íñigo Navarro-Fernández ID10, Concepción Román-Curto ID11, Hassani Mtenje9, Gerald Thauzeni12, Elizabeth Harawa13, Stephano Kaluzi14, Mphatso Diere15, Mary Mkandawire9, Shaibu Malizani9, Alex Chifundo9, Marta Utrera- Busquets ID16, Mónica Roncero-Riesco11, Sara López Martı́n-Prieto17, Iosune Vilanova- Urdániz18, Gisela H. Petiti ID19, Marı́a Victoria de Gálvez Aranda ID20, Nuria No Pérez21, Marı́a Rueda Gómez-Calcerrada22, Pilar Iranzo ID23, Pilar Escalonilla Garcı́a-Patos ID24, a1111111111 Magdalena de Troya-Martı́n ID25, Javier Romero Gomez ID26, Esther Cardeñoso-Alvarez11, a1111111111 Sofia Lucas Truyols ID27, Libe Aspe Unanue ID28, Cristina Bajo del Pozo29, Alicia Comunión a1111111111 Artieda30, Maria Isabel Martı́nez González28, Omar F. López-López31, Esther Moreno- a1111111111 Artero32, Xavier Cubiró ID33, Iago Meilán-Sánchez ID34, Alejandra Tomás-Velázquez ID35, a1111111111 Cristina López-Sánchez ID33, Eva M. Sánchez-Martı́nez ID36, Harrison A. Edwards ID37,38,39, Maria Herrera Morueco ID40, Julia Zehe Rubiera41, Laura Salguero Caldera42, Urbano Blanes-Moreno43, Maria Uribarren-Movilla44, Michael Marks ID45 1 Faculty of Medicine and Health Sciences, Universitat de Barcelona, Barcelona, Spain, 2 Department of Dermatology, Hospital Universitario de Mostoles, University Rey Juan Carlos, Madrid, Spain, 3 DerMalawi OPEN ACCESS Project, Nkhotakota, Malawi, 4 Fight AIDS and Infectious Diseases Foundation, Badalona, Spain, 5 Hospital Universitari Germans Trias i Pujol, Badalona, Spain, 6 Lihir Medical Centre-International SOS, Londolovit, Citation: Galván-Casas C, Mitjá O, Esteban S, Lihir Island, Papua New Guinea, 7 Department of Dermatology, Hospital Universitario de Cruces, Bilbao, Kafulafula J, Phiri T, Navarro-Fernández Í, et al. Spain, 8 Nkhotakota District Hospital, Nkhotakota, Malawi, 9 Alinafe Health Center, Njewa, Malawi, (2021) A facility and community-based 10 Department of Dermatology, Hospital Universitario de Cabueñes, Gijón, Spain, 11 Department of assessment of scabies in rural Malawi. PLoS Negl Dermatology, Complejo Asistencial Universitario de Salamanca, Salamanca, Spain, 12 Mwansambo Health Trop Dis 15(6): e0009386. https://doi.org/10.1371/ Center, Mwansambo, Malawi, 13 Kapiri Health Center, Kapiri, Malawi, 14 Benga Health Center Benga, journal.pntd.0009386 Malawi, 15 Thavite Health Center, Thavite, Malawi, 16 Department of Dermatology, Hospital General La Mancha Centro, Ciudad Real, Spain, 17 Consulta privada, Seville, Spain, 18 Department of Dermatology, Editor: David John Chandler, Brighton and Sussex Hospital General Universitario de Elche, Alicante, Spain, 19 Department of Dermatology, Hospital Mòisses University Hospitals NHS Trust, UNITED KINGDOM Broggi, Barcelona, Spain, 20 Faculty of Medicine, Universidad de Málaga, Málaga, Spain, 21 Department of Dermatology, Complejo Hospitalario Universitario de Vigo, Vigo, Spain, 22 Department of Dermatology, Received: September 3, 2020 Hospital Viamed Virgen de la Paloma, Madrid, Spain, 23 Department of Dermatology, Hospital Clı́nic, Barcelona, Spain, 24 Department of Dermatology, Complejo Asistencial de Ávila, Ávila, Spain, Accepted: April 14, 2021 25 Department of Dermatology, Hospital Costa del Sol, Marbella, Spain, 26 Department of Dermatology, Published: June 1, 2021 Hospital Quironsalud, Málaga, Spain, 27 Department of Dermatology, Consorci Hospital General Universitari, València, Spain, 28 Department of Dermatology, Hospital Universitario Araba, Vitoria-Gasteiz, Copyright: © 2021 Galván-Casas et al. This is an Spain, 29 Department of Dermatology, Complejo Hospitalario de Palencia, Palencia, Spain, 30 Department open access article distributed under the terms of of Dermatology, Centro de Diagnóstico Médico, Ayuntamiento de Madrid, Madrid, Spain, 31 Consulta the Creative Commons Attribution License, which privada, A Coruña, Spain, 32 Department of Dermatology, Clı́nica Universidad de Navarra, Madrid, Spain, permits unrestricted use, distribution, and 33 Department of Dermatology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain, 34 Department of reproduction in any medium, provided the original Dermatology, Complexo Hospitalario Universitario A Coruña, A Coruña, Spain, 35 Department of author and source are credited. Dermatology, Clı́nica Universidad de Navarra, Pamplona, Spain, 36 Department of Dermatology, Hospital Universitario Doctor Peset, Valencia, Spain, 37 Department of Dermatology, Princess Alexandra Hospital, Data Availability Statement: All relevant data are Brisbane, Australia, 38 School of Public Health, University of Queensland, Brisbane, Australia, within the manuscript and its Supporting 39 Dermatology Research Centre, University of Queensland, Diamantina Institute, Brisbane, Australia, Information files. 40 Department of Internal Medicine, Hospital Universitario Infanta Leonor, Madrid, Spain, 41 Hospital Plat, Barcelona, Spain, 42 Hospital Universitario Germans Trias y Pujol, Barcelona, Spain, 43 Francisco de Funding: This work was supported by donations Vitoria University, Madrid, Spain, 44 Alcalá University, Madrid, Spain, 45 Clinical Research Department, from individuals, companies (CantabriaLabs, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, Martiderm and Italfarmaco), The State Foundation, United Kingdom Health, Childhood and Social Welfare (FCSAI), Ayuntamiento de Villanueva de la Cañada, and * galvancasascristina@gmail.com students from Secondary School “Las Encinas” from Villanueva de la Cañada, Madrid (Spain) as well as an international Cooperation Awards from PLOS Neglected Tropical Diseases | https://doi.org/10.1371/journal.pntd.0009386 June 1, 2021 1 / 11 PLOS NEGLECTED TROPICAL DISEASES Scabies control in Malawi the Spanish Academy of Dermatology (CG), the Colegio Oficial de Médicos de Madrid (CG), the Abstract Fundación Mutua Madrileña (CG) and the Central Background section of the Spanish Academy of Dermatology (CG). Additonal funding support was provided by Scabies is a neglected tropical disease of the skin, causing severe itching, stigmatizing skin the Celia Delgado Matı́as Association and the lesions and systemic complications. Since 2015, the DerMalawi project provide an inte- University of Salamanca.The funders had no role in grated skin diseases clinics and Tele-dermatology care in Malawi. Clinic based data sug- study design, data collection and analysis, decision to publish, or preparation of the manuscript. gested a progressive increase in scabies cases observed. To better identify and treat individuals with scabies in the region, we shifted from a clinic-based model to a community Competing interests: The authors have declared that no competing interests exist. based outreach programme. Methodology/Principal findings From May 2015, DerMalawi project provide integrated skin diseases and Tele-dermatologi- cal care in the Nkhotakota and Salima health districts in Malawi. Demographic and clinical data of all patients personally attended are recorded. Due to a progressive increase in the number of cases of scabies the project shifted to a community-based outreach programme. For the community outreach activities, we conducted three visits between 2018 to 2019 and undertook screening in schools and villages of Alinafe Hospital catchment area. Treatment was offered for all the cases and school or household contacts. Scabies increased from 2.9% to 39.2% of all cases seen by the DerMalawi project at clinics between 2015 to 2018. During the community-based activities approximately 50% of the population was assessed in each of three visits. The prevalence of scabies was similar in the first two rounds, 15.4% (2392) at the first visit and 17.2% at the second visit. The prevalence of scabies appeared to be lower (2.4%) at the third visit. The prevalence of impetigo appeared unchanged and was 6.7% at the first visit and 5.2% at the final visit. Conclusions/Significance Prevalence of scabies in our setting was very high suggesting that scabies is a major public health problem in parts of Malawi. Further work is required to more accurately assess the burden of disease and develop appropriate public health strategies for its control. Author summary Scabies is an infestation of the skin caused by a mite. There is limited data on how com- mon scabies is in sub-Saharan Africa, including Malawi. The DerMalawi project has been providing care for dermatological conditions in rural Malawi since 2015. Between 2015 and 2018 we observed an increase in patients with scabies attending for treatment. In response the project shifted from providing care at clinics to an approach using commu- nity-based outreach. Between 2018 and 2019 we conducted community-based activities on three occasions in an area of approximately 30,000 individuals. The DerMalawi team visited schools and villages to identify and treat cases of scabies and their contacts. We were able to examine about 50% of the population on each visit. Initially a large propor- tion of the population had scabies (15%) and this was similar during our second commu- nity survey. At our third survey this appeared to have decreased to 2% but it is difficult for us to know if this is because of treatment given in the previous rounds. Scabies is a major PLOS Neglected Tropical Diseases | https://doi.org/10.1371/journal.pntd.0009386 June 1, 2021 2 / 11 PLOS NEGLECTED TROPICAL DISEASES Scabies control in Malawi problem in rural populations in Malawi and public health strategies are needed to reduce the disease burden. Introduction Scabies is a skin disease caused by infestation with the mite, Sarcoptes scabiei var. Hominis. Human transmission is predominantly via skin-to-skin contact. Around 200–300 million peo- ple are affected each year [1, 2], particularly among poor populations living in crowded condi- tions in tropical areas. Until recently there has been limited data on the epidemiology of scabies in sub-Saharan Africa and in particular limited population level estimates of disease prevalence[3]. More recent data from Ethiopia, Liberia and Ghana all suggest that scabies is a major public health problem in sub-Saharan Africa[4–6]. Permethrin 5% topical ointment is widely considered the first line treatment for treatment of individuals with scabies[7] but there is increasing evidence that community wide treatment with ivermectin is the best strategy for control in highly endemic areas. The major challenge to the use of ivermectin is the current recommendation for two separated doses and its relative contraindication in pregnant and breastfeeding women and children under five years of age. [8–13]. Standard guidelines for scabies control are based on treatment of cases and contacts [14], but this approach is not effective in highly-endemic areas [15–17]. Different mass treatment approaches have resulted in positive outcomes [18–20] Mass drug administration of ivermec- tin as part of lymphatic filariasis control in Zanzibar was associated with a 68% decrease of sca- bies treatment’s prescription[21]. The first comparative trial of mass drug administration for scabies was the Skin Health Intervention Fiji Trial (SHIFT) which found that ivermectin- based mass drug administration decreased the prevalence of scabies by 94% 1 year after the intervention, and was superior to both mass drug administration of topical permethrin and standard care[9]. Better data is needed on the epidemiology of scabies in sub-Saharan Africa. We report facil- ity and community based data on scabies in rural Malawi, collected as part of the DerMalawi project. Methods Ethics statement The findings reported in this paper reflect data collected during routine clinical health work, while the patients’ screening and treatment was organized in local schools or villages as opposed to distant clinics. Routine clinical health work does not require IRB approval. These arrangements were approved by the Malawi health authorities (Nkhotakota District Health Officer) who requested the clinical health work which is the base of the study and agreed with the study related data collection and handling. All participants provided oral informed consent in the presence of witnesses and in their mother language (Chichewa). The DerMalawi project There is limited access to dermatology in Malawi with only two trained dermatologists in the country. The DerMalawi project (http://www.dermalawi.com/) is an ongoing project in collab- oration with the Malawian Health authorities that was established in May 2015 to provide inte- grated skin diseases care and Tele-dermatological consultations to communities in the PLOS Neglected Tropical Diseases | https://doi.org/10.1371/journal.pntd.0009386 June 1, 2021 3 / 11 PLOS NEGLECTED TROPICAL DISEASES Scabies control in Malawi Fig 1. Map of Malawi indicating the location of the DerMalawi Project (Base layer: https://commons.wikimedia. org/wiki/File:Malawi_Base_Map.png). https://doi.org/10.1371/journal.pntd.0009386.g001 Nkhotakota and Salima health districts in Malawi (Fig 1). The project is governed by a memo- randum of understanding between a group of Spanish dermatologists and the Malawian Health authorities. As part of the project Dermatologists are approved to work in the area from the Malawi Medical Council and local oversite for clinical work is provided by the Nkho- takota (Malawi) District Medical Officer. The Benga Parish Missionary Community San Paul de Apostle (MCSPA) acts as institutional liaison in Malawi between the project partners. The DerMalawi team comprises Spanish dermatologists, staff from Alinafe Hospital, trained Chi- chewa-English translators and community health manager. We report here on activities con- ducted between 2015–2019 (Fig 2). Clinic based data collection Since the beginning of the DerMalawi project individuals with any skin problem were invited to attend for facility-based skin screening. As part of these activities the demographic and clini- cal data of all patients are recorded in spreadsheet, using tablets. Among the clinical data we collected personal and family history, symptoms, dermatological examination, complementary PLOS Neglected Tropical Diseases | https://doi.org/10.1371/journal.pntd.0009386 June 1, 2021 4 / 11 PLOS NEGLECTED TROPICAL DISEASES Scabies control in Malawi Fig 2. Timings of activities conducted by the DerMalawi Project 2015–2020. https://doi.org/10.1371/journal.pntd.0009386.g002 examinations performed, coded diagnosis (ICD-10) and prescribed and administered treat- ment. This data included basic information on the number of individuals assessed and the number of cases of major common skin conditions based on clinical diagnosis. Between May 2015 to March 2018, clinic-based data suggested that there had been a progressive increase in the proportion and absolute number of cases of scabies seeking care. In response, the Malawi Health authorities requested the DerMalawi project to shift from a clinic-based model to a community-based outreach programme to try and better identify and treat individuals with scabies in the region. This screening and treatment strategy was developed between the Der- Malawi project and the Malawian Health and Educational Authorities. Community based data collection Community outreach activities took place in the Alinafe Health Center catchment area, Nkho- takota and Salima districts, Malawi, which has a population of approximately 30,000 individu- als. Three rounds of community dermatology outreach activities were conducted between July 2018 and April 2019 in both schools and communities. A week before each round we conducted health awareness at community meetings, school meetings and through public notices, pamphlets and posters in cooperation with village leaders. These activities were conducted by Malawian health staff in collaboration with the DerMalawi project and explained the background and purpose of the community-based activities. The Der- Malawi team visited schools class by class and in villages attempted to go house by house trying to reach all individuals present at the school or at home. All individuals were invited for skin screening regardless of whether they reported itch of a skin problem. A private area was setup for screening at each house or school visited. As with clinic-based data collection we collected information on the number of individuals seen and demographics but focused clinical examina- tion on scabies and impetigo in view of the marked increase we had seen at the health facility. Examination In both clinic and community settings a dermatologist carried out a standardized skin exami- nation. Scabies was classified on the basis of a clinical diagnosis by a trained dermatologist. Dermatoscopy was used in cases of uncertainty. Impetigo was defined on the basis of a clinical examination without microbiological confirmation based on the presence of pustules, sores and adherent golden crusts. Treatment All individuals diagnosed with scabies were offered two doses of oral ivermectin (200 μg per kilogram of body weight) or topical permethrin cream where ivermectin was contra-indicated PLOS Neglected Tropical Diseases | https://doi.org/10.1371/journal.pntd.0009386 June 1, 2021 5 / 11 PLOS NEGLECTED TROPICAL DISEASES Scabies control in Malawi (pregnancy, breastfeeding, weight under 15kg). The first dose was given under direct supervi- sion. The team returned after 7–14 days to provide a second dose. We attempted to provide treatment to all class-mates where cases of scabies were found during school visits and to the household of cases of found during either school or household visits. Medication was provided by the DerMalawi project with approval from the Malawian Health Authorities. Analysis The DerMalawi project area has 14 schools, 94 villages and five health facilities. For the pur- pose of project implementation, we grouped schools and their surrounding villages into groups and visited each in turn. A school and its linked villages were considered as a single school-catchment area for the purpose of analysis. For clinic based data we report the absolute number of cases of scabies and the proportion of all skin problems seen that were due to sca- bies. For the community data we report the prevalence of scabies (with and without secondary bacterial infection), for each school catchment area, and the overall DerMalawi project area. Results DerMalwi project acitivites The population living in the catchment area of the Alinafe Health Centre is estimated at 29,780 people (2018 census). Between 2015 and 2019 the DerMalawi Project conducted 4 health cen- tre based clinics and three community based skin screening activities. Facility based activities A total of 4,769 people were assessed as part of facility-based skin screening. The proportion and absolute number of scabies diagnosed increased from 13 (2.8%) individuals in 2015 to 792 (38.7%) individuals in 2018. There appeared to be decline in the number of cases of fungal infections seen but no significant changes in the proportions of any other key diseases (Table 1). Community based activities A total of 15,487 (52% of catchment are population) were screened in July 2018, followed by 16,619 (55.8%) in October 2018 and 12,617 (42.4%) in April 2019 (Table 2). The prevalence of scabies was similar during our first two community visits; 15.4% (2392) in July 2018 and 17.2% (2855) in October 2018 but only 2.4% in April 2019. All individuals diagnosed with sca- bies received treatment with IVM but only 47% of cases seen in the first community visit and only 55% of cases seen during the second community visit received an observed second dose Table 1. Cases seen during clinic-based activities. Diagnosis May 2015 June2016 August 2017 August 2018 Scabies 13 (2.9%) 9 (1.2%) 146 (15.2%) 792 (39.2%) Leprosy 5 (1.1%) 6 (0.8%) 10 (1.0%) 4 (0.2%) Impetigo 18 (3.9%) 24 (3.1%) 27 (2.8%) 46(2.3%) Skin ulcer 3 (0.7%) 4(0.5%) 8 (0.8%) 30 (1.5%) Skin Cancer 16 (3.5%) 28 (3.6%) 40 (4.2%) 33 (1.6%) Fungal disease 192 (42.1%) 243(31.3%) 334 (34.8%) 536 (26.6%) Total 456 776 960 2018 https://doi.org/10.1371/journal.pntd.0009386.t001 PLOS Neglected Tropical Diseases | https://doi.org/10.1371/journal.pntd.0009386 June 1, 2021 6 / 11 PLOS NEGLECTED TROPICAL DISEASES Scabies control in Malawi Table 2. Individuals seen during community based activities. July 2018 (N = 15487) October 2018 (N = 16619) April 2019 (N = 12617) Age Group 0-4yrs 2384 (15.4%) 1894 (11.4%) 2143 (17.0%) 5-9yrs 3411 (22.0%) 4242 (25.5%) 2626 (20.8%) 10-14yrs 3994 (25.8%) 5490 (33.0%) 2933 (23.2%) 15-24yrs 2402 (15.5%) 2259 (13.6%) 2033 (16.1%) 24-34yrs 1344 (8.7%) 1106 (6.7%) 1120 (8.9%) > = 35yrs 1952 (12.6%) 1628 (9.8%) 1762 (14.0%) Gender Female 8714 (56.3%) 9152 (55.1%) 7246 (57.4%) Male 6773 (43.7%) 7467 (44.9%) 5371 (42.6%) Scabies 2392 (15.4% - 95%CI 14.9–16.0%) 2855 (17.2% - 95% CI 16.6–17.8%) 303 (2.4% - 95% CI 2.1–2.7%) Impetigo 1032 (6.7% - 95%CI 6.3–7.1%) 704 (4.2% - 95%CI 3.9–4.6%) 658 (5.2% - 95% CI 4.8–5.6%) https://doi.org/10.1371/journal.pntd.0009386.t002 of treatment. As well as index cases, 5,204 individuals and 7,888 individuals received treatment as contacts during these visits. At each community visit the prevalence of scabies varied markedly between villages (range 5–40%, Fig 3). The prevalence of scabies was highest amongst children under 5 (Table 3) at each visit. No cases of crusted scabies were found. The prevalence of impetigo was 6.7% (1032), 4.2% (704), and 5.2% (658) across the three visits. Discussion There is limited data on the prevalence of scabies in much of sub-Saharan Africa although sev- eral recent studies suggest that it is common[22]. There have been large scale outbreaks of sca- bies reported from Ethiopia[4, 22] in the context of drought, and reports from both rural and peri-urban regions of West Africa demonstrating high prevalences of scabies[5, 6, 23]. Prior to the DerMalawi project there has been no recent data on scabies in Malawi. The data from the DerMalawi project suggests that scabies is a major problem in the area with especially high prevalences amongst children. In keeping with data from other parts of sub-Saharan Africa we did not notice a particularly high burden of impetigo compared to that reported in the Pacific region[24, 25]. The DerMalawi project has been working in Malawi since 2015. Over that time we noted a marked increase in presentations to our service for scabies. When we switched to a community rather than a clinic based model we found an extremely high community prevalence of scabies of 15%. Over the course of three community outreach activities the prevalence appeared to decline markedly but whether this reduction is directly related to our activities and treatment is unclear. There was no change in scabies prevalence between July 2018 and October 2018 suggesting that at the coverage achieved the treatment of cases and a proportion of their contacts was inadequate to affect scabies prevalence. This lack of change is likely due to low population cov- erage. We did not record when people declined to be examined but based on the number of people seen and the known population of the Alinafe catchment area, when we switched from a clinic to a community based strategy we still reached only about 50% of the population. Such low coverage invariably leads to a large number of untreated scabies cases that might act as a reservoir for infection. In addition, most individuals received only a single observed dose of ivermectin limiting the efficacy of treatment for individual patients. All three visits were con- ducted during the dry season, so differences in prevalence seem unlikely to be related to sea- sonality[23]. However given the before and after nature of the data we can not exclude other PLOS Neglected Tropical Diseases | https://doi.org/10.1371/journal.pntd.0009386 June 1, 2021 7 / 11 PLOS NEGLECTED TROPICAL DISEASES Scabies control in Malawi Fig 3. Scabies prevalence by village at each of the three community outreach events conducted by the DerMalawi Project. https://doi.org/10.1371/journal.pntd.0009386.g003 Table 3. Prevalence of scabies and impetigo by age group during each visit. Visit 1 Visit 2 VISIT 3 Age Prevalence of Scabies % Prevalence of Impetigo % Prevalence of Scabies % Prevalence of Impetigo % Prevalence of Scabies% Prevalence of Group (95% CI) (95% CI) (95% CI) (95% CI) (95% CI) Impetigo 0–4 20.6% 10.5% 22.3% 5.5% 4% 6% (19–22.2%) (9.3–11.8%) (20.4–24.2%) (4.6–6.7%) (3.2–4.9%) (5.1–7.1%) 05–10 16% 7.9% 18.2% 5.2% 3.2% 9.1% (14.8–17.3%) (7–8.9%) (17–19.4%) (4.5–5.9%) (2.6–4%) (8–10.3%) 10–14 15.8% 7.2% 18.7% 4.7% 2.8% 7% (14.7–17%) (6.4–8%) (17.7–19.8%) (4.1–5.3%) (2.2–3.5%) (6.1–8%) 15–24 14.7% 5.2% 15.2% 3.3% 1.3% 2.9% (13.3–16.1%) (4.3–6.1%) (13.8–16.8%) (2.6–4.1%) (0.9–1.9%) (2.2–3.7%) 25–34 13.7% 3.9% 11.2% 1.7% 1% 1.1% (11.9–15.7%) (3–5.2%) (9.4–13.3%) (1.1–2.7%) (0.5–1.8%) (0.6–1.9%) �35 9.7% 2.5% 10.3% 1.8% 0.9% 0.8% (8.4–11.1%) (1.9–3.3%) (8.9–11.9%) (1.3–2.7%) (0.5–1.4%) (0.5–1.4%) https://doi.org/10.1371/journal.pntd.0009386.t003 PLOS Neglected Tropical Diseases | https://doi.org/10.1371/journal.pntd.0009386 June 1, 2021 8 / 11 PLOS NEGLECTED TROPICAL DISEASES Scabies control in Malawi secular changes in scabies prevalence, which have been observed in some settings. Unlike research interventions that have been carried out in islands or confined populations and have maintained the effects for years [17], the activities reported here were carried out as part of a long term dermatological assistance programme and the patients in our target area, are sur- rounded by neighbouring communities with potentially high scabies rates. These surrounding areas therefore serve as a further reservoir from which reintroduction can occur. Strategies to improve programme coverage including more extended community outreach and potentially implementation on a larger scale, to avoid inward transmission from outside the area, should be considered as possible strategies. The markedly reduced prevalence observed in our visit in April 2019 despite low treatment coverage, and in the absence of any effect seen previously, suggests that the observed reduction is unlikely to be due to treatment and more likely reflects changes in the population assessed at each time point. In keeping with this there were differences in both the demographic structure of the population seen in our final community visit and in the number of people seen at each screening site across each of our visits. We noted that in the final visit a higher proportion of individuals declined examination particularly in the absence of self-reported itch. For these reasons it seems likely that the reduction seen is most likely a reflection of sampling bias not a true difference. Scabies remains as an unresolved matter for global health, continues to be widespread and is responsible for intense suffering, health and social complications. New drugs, dissemination models and treatment and preventive strategies are needed to achieve better results. Targets for the establishment of scabies control programmes have been included in the new WHO NTD Roadmap 2021–2030 and our data suggests such a programme should be considered in Malawi alongside other national NTD programmes. Supporting information S1 Project Dataset. Patients attended; Scabies, Impetigo and demographic data. (XLSX) Acknowledgments We are grateful to the Missionary Community San Paul the apostle MCSPA for providing accommodation and support for the DerMalawi project, especially Mr. Brian Odhiambo who supports all the dermatological work carried out by the DerMalawi project and F. Manuel Her- nandez, head of the parish. We are extremely grateful to all the members of the community, community leaders for their participation and support of the DerMalawi project over many years. Author Contributions Conceptualization: Cristina Galván-Casas. Data curation: Sara Esteban, Íñigo Navarro-Fernández. Formal analysis: Oriol Mitjá, Michael Marks. Funding acquisition: Cristina Galván-Casas. Investigation: Cristina Galván-Casas, Sara Esteban, Texon Phiri, Íñigo Navarro-Fernández, Concepción Román-Curto, Hassani Mtenje, Gerald Thauzeni, Elizabeth Harawa, Stephano Kaluzi, Mphatso Diere, Mary Mkandawire, Shaibu Malizani, Alex Chifundo, Marta Utrera- Busquets, Mónica Roncero-Riesco, Sara López Martı́n-Prieto, Iosune Vilanova-Urdániz, PLOS Neglected Tropical Diseases | https://doi.org/10.1371/journal.pntd.0009386 June 1, 2021 9 / 11 PLOS NEGLECTED TROPICAL DISEASES Scabies control in Malawi Gisela H. Petiti, Marı́a Victoria de Gálvez Aranda, Nuria No Pérez, Marı́a Rueda Gómez- Calcerrada, Pilar Iranzo, Pilar Escalonilla Garcı́a-Patos, Magdalena de Troya-Martı́n, Javier Romero Gomez, Esther Cardeñoso-Alvarez, Sofia Lucas Truyols, Libe Aspe Unanue, Cris- tina Bajo del Pozo, Alicia Comunión Artieda, Maria Isabel Martı́nez González, Omar F. López-López, Esther Moreno-Artero, Xavier Cubiró, Iago Meilán-Sánchez, Alejandra Tomás-Velázquez, Cristina López-Sánchez, Eva M. Sánchez-Martı́nez, Harrison A. Edwards, Maria Herrera Morueco, Julia Zehe Rubiera, Laura Salguero Caldera, Urbano Blanes-Moreno, Maria Uribarren-Movilla. Methodology: Oriol Mitjá, Michael Marks. Project administration: Cristina Galván-Casas, Jacob Kafulafula. Supervision: Cristina Galván-Casas, Oriol Mitjá, Jacob Kafulafula, Texon Phiri, Michael Marks. Writing – original draft: Cristina Galván-Casas. Writing – review & editing: Oriol Mitjá, Sara Esteban, Jacob Kafulafula, Texon Phiri, Íñigo Navarro-Fernández, Concepción Román-Curto, Hassani Mtenje, Gerald Thauzeni, Eliza- beth Harawa, Stephano Kaluzi, Mphatso Diere, Mary Mkandawire, Shaibu Malizani, Alex Chifundo, Marta Utrera-Busquets, Mónica Roncero-Riesco, Sara López Martı́n-Prieto, Iosune Vilanova-Urdániz, Gisela H. 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