The Dismal Worldwide State of Scabies Treatment

The skin disease scabies is like the television show Grey’s Anatomy: It’s been around forever, and you may, every now and again, find yourself wondering, “Is that thing still around?” In both cases, unfortunately, the answer is a definitive “yes.”

Only one of the two isn’t marching slowly toward its inexorable and merciful death: Scabies remains one of the most common skin disorders in children and affects as many as 300 million people worldwide. A recent article in BMC Infectious Diseases paints a sobering picture of current and future treatments for scabies, including a particularly distasteful reason behind the lack of clinical developments for treating scabies. The reason? The disease is mostly concentrated in poor or underdeveloped countries, international awareness of scabies, and associated prevention and treatment efforts, are just about nonexistent.

Scabies is frequently complicated by bacterial infection leading to the development of skin sores and other more serious consequences, such as septicaemia and chronic heart and kidney diseases. Few treatment options are available, but perhaps even worse, some scabies mites are developing resistance to established scabicides.

The clinical consequences of this dearth of effective treatment options are clearly spelled out in the review. Among the concerns listed by the authors:

• Even diagnosing scabies is difficult. Identifying scabies mite from a patient’s skin is challenging, and a negative result by even experienced clinical staff, does not rule out scabies.
• None of the current treatments for scabies have ovicidal, antibacterial, anti-inflammatory and/or anti-pruritic properties.
• There is no international consensus on the appropriate schedule for scabies treatment, and recommendations in one nation may not be appropriate in others.
• The first line treatment options are topical agents and require whole body application for many hours.
• People who have been in close contact where scabies has been diagnosed should be treated simultaneously, as they may be infected without yet manifesting symptoms. But the logistics involved in simultaneous treatment can be daunting, because it should include identification and treatment of all contacts of an index case, including family members, other coinhabitants, and medical and other supporting staff and others who may come in contact with the index cases.
• Treatments are potentially hazardous and are associated with moderate to severe side effects, including secondary eczematisation, oedema, erosions and/or pyoderma.
• The development of new chemical entities is doubtful in the near future. “Though there may be potential for immunological control, the development of a vaccine or other immunotherapy modalities may be decades away,” the authors note.

The authors hope the review will trigger not just greater awareness of the problem, but the development of better diagnostic tools and protocols for long-term adherence to the few treatments that are available.