Lessons from the Field Control of scabies, skin sores and haematuria in children in the Solomon Islands: another role for ivermectin Gregor Lawrence,1 Judson Leafasia,2 John Sheridan,3 Susan Hills,4 Janet Wate,5 Christine Wate,5 Janet Montgomery,6 Nirmala Pandeya,1 & David Purdie1 Objective To assess the effects of a 3-year programme aimed at controlling scabies on five small lagoon islands in the Solomon Islands by monitoring scabies, skin sores, streptococcal skin contamination, serology and haematuria in the island children. Methods Control was achieved by treating almost all residents of each island once or twice within 2 weeks with ivermectin (160–250 µg/kg), except for children who weighed less than 15 kg and pregnant women, for whom 5% permethrin cream was used. Reintroduction of scabies was controlled by treating returning residents and visitors, whether or not they had evident scabies. Findings Prevalence of scabies dropped from 25% to less than 1% (P < 0.001); prevalence of sores from 40% to 21% (P < 0.001); streptococcal contamination of the fingers in those with and without sores decreased significantly (P = 0.02 and 0.047, respectively) and anti-DNase B levels decreased (P = 0.002). Both the proportion of children with haematuria and its mean level fell (P = 0.002 and P < 0.001, respectively). No adverse effects of the treatments were seen. Conclusion The results show that ivermectin is an effective and practical agent in the control of scabies and that control reduces the occurrence of streptococcal skin disease and possible signs of renal damage in children. Integrating community-based control of scabies and streptococcal skin disease with planned programmes for controlling filariasis and intestinal nematodes could be both practical and produce great health benefits. Keywords Scabies/drug therapy/complications; Ivermectin/administration and dosage; Permethrin/therapeutic use; Pyoderma/ microbiology; Skin ulcer/microbiology; Streptococcus pyogenes; Nephritis/etiology; Hematuria; Solomon Islands (source: MeSH, NLM). Mots clés Gale/chimiothérapie/complication; Ivermectine/administration et posologie; Perméthrine/usage thérapeutique; Ulcère cutané/microbiologie; Pyodermite; Streptococcus pyogène; Néphrite/étiologie Hématurie; Iles Salomon (source: MeSH, INSERM). Palabras clave Escabiosis/quimioterapia/complicaciones; Ivermectina/administración y dosificación; Permetrina/uso terapéutico; Pioderma/microbiología; Ulcera cutánea/microbiología; Streptococcus pyogenes; Nefritis/etiología; Hematuria; Islas Salomón (fuente: DeCS, BIREME). Bulletin of the World Health Organization 2005;83:34-42. Voir page 40 le résumé en français. En la página 41 figura un resumen en español. Introduction bies, was very carefully treated with topical permethrin cream. Scabies and streptococcal skin disease are a burden in crowded With no other treatment, streptococcal pyoderma decreased communities and are among the most common presentations to markedly after scabies control. Treating returnees and visitors health services (1). Costs to families and services are high and the with permethrin maintained these benefits (4). However this diseases have long-term implications through post-streptococcal methodology has not been widely adopted because it is messy, renal disease and possibly rheumatic heart disease (2, 3). time-consuming, and intrusive. In 1991 Taplin et al. reported excellent scabies control Orally administered ivermectin is active against scabies. in a community where everyone, whether or not they had sca- It is used in the mass annual treatment of millions of people 1 Australian Centre for International and Tropical Health and Nutrition, Queensland Institute of Medical Research, Post Office, Royal Brisbane Hospital, Queensland 4029, Australia. Correspondence should be sent to Dr Lawrence (email: [email protected]). 2 Solomon Island Medical Training and Research Institute, Honiara, Solomon Islands. 3 Indooroopilly, Brisbane, Australia. 4 Queensland Health Tropical Public Health Unit, Queensland, Australia. 5 Sulufou and Fouia Villages, Malaita Province, Solomon Islands. 6 Mater Hospital, South Brisbane, Australia. Ref. No. 04-011197 (Submitted: 7 January 2004 – Final revised version received: 11 October 2004 – Accepted: 12 October 2004) 34 Bulletin of the World Health Organization | January 2005, 83 (1) Lessons from the Field Gregor Lawrence et al. Ivermectin in control of scabies, skin sores and haematuria, Solomon Islands for onchocerciasis (5) and filariasis. Treatment has been found Fig. 1. Study timeline to be safe except in people with loaiasis who have high micro- filaraemia (6). Ivermectin is the usual treatment for scabies in domestic animals and has been used successfully for this pur- pose in humans (7–9). In cases of ordinary scabies, one dose of Visit number Sulufou Foueda Funafou ivermectin is effective (10–12). One-dose treatment is crucial Addagege to practicality in community settings. Nuileni Acute nephritis following pyoderma is well-recognized. Subclinical renal damage from multiple skin infections in child- Diagnosis Diagnosis hood might contribute to the pathogenesis of renal and cardio- 1/ July 1997 Culture and tests Culture and tests Nil vascular disease in adult life. Recently, in a population where Mass treatment No treatment end-stage renal disease was extremely common, it was found that many factors including scabies and previous nephritis were Diagnosis Diagnosis independently associated with a raised urinary albumin-to- 2/ November1997 Culture and tests Culture and tests creatinine ratio (13). It is not clear how much of the haematuria Case treatment Mass treatment found in children in developing countries is causally related to the many skin infections they experience, although they are 3–9/ Diagnosis correlated (14). Haematuria may be a sensitive indicator of February 1998– Culture and tests low-level damage, as tubular reabsorption of protein after minor June 2000 Case treatment glomerular leakage of red cells and protein may leave haema- turia as the only sign. WHO 04.191 We predicted that scabies control would lead to reduc- tions in sores, in haematuria, and in the group A streptococci (GAS) present in the communities involved. Ethics Committee and by the Queensland Institute of Medical Research Human Research Ethics Committee. The study ran from July 1997 until June 2000 and reviews were conducted Methods three times per year (Fig. 1). Two retired local female health Rationale workers who were respected in the community were trained This was a trial of scabies control in a practical context, to as- and employed to implement the project. sess the feasibility and effects of treating a whole population at once and then maintaining control over a period, with limited Baseline assessment and treatment input, while people went about their normal lives. The islands In July 1997, children on Sulufou and Foueda aged 12 years or selected were very crowded and scabies common. The island under were examined for scabies and sores and specimens were location helped define the area and the population to be man- collected from cooperating children. At that first visit the aged as residents came and went. No continuing comparison of whole population of Sulufou was offered treatment, whereas treated and untreated groups within the population was pos- no treatment was given to people on Foueda who acted as a sible because of the underlying principle of the intervention: i.e. control population. In November 1997 the children present on the need to treat everyone, thus removing all scabies mites and Foueda and the remaining islands were examined and medica- preventing reinfection. Orally administered ivermectin was the tion offered to everyone (see timeline). Information on adverse major agent used, because effective topical treatment of large events was sought. numbers is so difficult as to be unacceptable and impracticable. As much of each child’s skin as was accessible without We investigated the relationships between scabies, pyoderma, embarrassment for children of each age was examined. The ef- renal damage and GAS in sores and on the fingers of children fects on the analysis of a few older children having lesions that in the community. We considered this strategy reasonable and were confined to their genitals was considered acceptable be- likely to reflect the presence of scabies in the population as the cause about 90% of people with scabies have lesions on their prevalence in children is generally higher than that in adults. hands and arms (15) and some of the other 10% would have Also post-streptococcal disease is largely confined to children. In visible lesions on the lower limbs and trunk. Scabies in chil- practice, children tend to be more easily available and tolerant dren was diagnosed clinically by one investigator on the basis of imposition than adults. of the nature and distribution of lesions (16). These included findings such as pruritic papulonodular and vesicular lesions Setting and population on the hands, arms, wrists, feet, thighs, trunk and buttocks. We studied the people of five small densely-populated islands Also, a more generalized symmetrical papulonodular eruption (Sulufou, Foueda, Nuileni, Funafou and Addagege) in the Lau contributed to some diagnoses, as did acropustulosis in some Lagoon, Malaita Province, Solomon Islands. Our census in- infants. Where findings were suggestive, but not definitive, a cluded 1558 people, about half of whom were on the islands diagnosis of possible scabies was recorded.