Albonico, M, Becker, Sl, Odermatt, P, Angheben, A, Anselmi, M, Amor, A, Barda, B, Buonfrate, D, Cooper, P, Getaz, L, Keiser, J, Khieu, V, Montresor, A, Munoz, J, Requena-Mendez, A, Savioli, L, Speare, R, Steinmann, P, van Lieshout, L, Utzinger, J, Bisoffi, Z, StrongNet Working Group: Ault, S, Bartoloni, A, Bottazzi, Me, Bottieau, E, Bradbury, R, Brattig, N, Calleri, G, Castel, M, Caumes, E, Chiodini, Pl, Colli, E, de los Santos JJ, Einsiedel, L, Ferrero, L, Formenti, F, Forrer, A, Gétaz, L, Gobbi, F, Gombe-Goetz, S, Gomez, J, Gotuzzo, E, Guevara, A, Kearns, T, Knopp, S, Kotze, A, Krolewiecki, A, Lammie, P, Luchanez, A, Magnussen, P, Marcos, L, Marlais, T, Marti, H, Mccarthy, J, Mejia, R, Mena, Ma, Mertens, P, Miles, M, Molina, I, Mueller, A, Muñoz, J, Muth, S, Neumayr, A, Nickel, B, Nutman, T, Olsen, A, Page, W, Perandin, F, Periago, Mv, Phongluxa, K, Polman, K, Raso, G, Requena-Méndez, A, Saboya, M, Sayasone, S, Seixas, J, Sevcsik, A-M, Schär, F, Sheorey, H, Shield, J, Arandes, As, Steer, A, Streit, A, Tanaka, T, Vercruysse, J, Verdonck, K, Visser, L, Vonghachack, Y, Weber, C, Yajima, A, and Zammarchi, L
Strongyloidiasis is a disease caused by an infection with a soil-transmitted helminth that affects, according to largely varying estimates, between 30 million and 370 million people worldwide [1,2]. Not officially listed as a neglected tropical disease (NTD), strongyloidiasis stands out as particularly overlooked [3]. Indeed, there is a paucity of research and public health efforts pertaining to strongyloidiasis. Hence, clinical, diagnostic, epidemiologic, treatment, and control aspects are not adequately addressed to allow for an effective management of the disease, both in clinical medicine and in public health programs [4]. The manifold signs and symptoms caused by Strongyloides stercoralis infection, coupled with the helminth’s unique potential to cause lifelong, persistent infection, make strongyloidiasis relevant beyond tropical and subtropical geographic regions, where, however, most of the disease burden is concentrated. Indeed, strongyloidiasis is acquired through contact with contaminated soil, and the infection is, thus, primarily transmitted in areas with poor sanitation, inadequate access to clean water, and lack of hygiene. While the actual morbidity of chronically infected, immunocompetent individuals is subtle and difficult to appreciate [5], the particular importance of this parasitic worm is linked to its potential for maintaining lifelong autoinfections and causing a life-threatening hyperinfection syndrome in immunocompromised individuals [6]. Lack of point-of-care (POC) diagnostics and poor availability of, and access to, ivermectin (the current treatment of choice) are the two most significant bottlenecks that hinder effective management of the disease both in clinical and in public health settings. Examples of the management and importance of strongyloidiasis in two clinical contexts (in a tropical setting and a high-income country) and from a public health perspective are given in Boxes 1–3. Box 1. Individual Living in an Endemic Area with Diarrhea, Abdominal Pain, Pruritus, and Significant Dermatological Manifestations [10] A 43-year-old male farmer, living in the rural eastern part of Preah Vihear province, northern Cambodia, was diagnosed with a heavy Strongyloides stercoralis infection (924 and 478 larvae present in two Baermann examinations). Additionally, larvae and adult S. stercoralis were detected in Koga agar plate culture examinations of the stools. The patient was co-infected with hookworm and presented with abdominal pain, diarrhea, nausea, vomiting, fever, and a pronounced and persistent skin rash, which had been present with extensive itching for more than two years. The rash was observed on the back, chest, abdomen, and extremities and, due to frequent and intense scratching, showed signs of focal infection. Three weeks after treatment with a single oral dose of ivermectin (200 μg/kg) and a single oral dose of mebendazole, the patient’s rash had almost disappeared, and he was free of episodes of intensive itching.