What’s Eating You? Scabies in the Developing World
Scabies infestation is a major cause of impetigo and subsequent renal failure in the developing world, and efforts to eradicate widespread infestation are underway. Ivermectin, topical sulfur, and topical benzyl benzoate often are used to treat widespread outbreaks.
Practice Points
- Scabies infestation is one of the world’s leading causes of chronic kidney disease.
- Ivermectin can be used to treat mass infestations, and older topical therapies also are commonly used.
Prevention and Control in the Developing World
Low-cost diagnostic equipment can play a key role in the definitive diagnosis and management of scabies outbreaks in the developing world. Micali et al28 found that a $30 videomicroscope was as effective in scabies diagnosis as a $20,000 videodermatoscope. Because of the low cost of benzyl benzoate, it is commonly used as a first-line drug in many parts of the world,13 whereas permethrin cream 5% is the standard treatment in the developed world.29 Recognition of the role of scabies in patients with pyoderma is key, and one study indicated clinically apparent scabies went unnoticed by physicians in 52% of patients presenting with skin lesions.30 Drug shortages also can contribute to a high prevalence of scabies infestation in the community.31 Mass treatment with ivermectin has proven to be an effective means of reducing the prevalence of many parasitic diseases,1,32,33 and it shows great promise for crusted scabies, institutional outbreaks, and mass administration in highly endemic communites.8 However, there is evidence of ivermectin tolerance among mites, which could undermine the success of mass drug administration.34 Another important consideration is population mobility and the risk for rapid reintroduction of scabies infection across regions.35
Complicating disease control are the socioeconomic factors associated with scabies in the developing world. Families with scabies infestation typically do not own their homes, are less likely to have constant electricity, have a lower monthly income, and live in substandard housing.20 Families can spend a substantial part of their household income on treatment, impacting what they can spend on food.8,11 In addition to medication, control of scabies requires community education and involvement, along with access to primary care and attention to living conditions and environmental factors.34,36
,