[Treatment of endemic scabies with allethrin, permethrin and ivermectin. Evaluation of a treatment strategy]

Abstract

Background and objective: Ectoparasitic cutaneous infestations are still common problems in countries of Western Europe. Scabies is a highly contagious disease of the skin caused by Sarcoptes scabiei variatio hominis. It has a world-wide distribution and affects all ages with no specific gender predisposition. Scabies is of profound public health interest because certain environment factors such as overcrowding, poor hygiene, delayed treatment of primary cases and lack of public enlightenment are conducive to its spread. However, prompt and adequate therapy is rewarding and prevents further spreading. Scabies acquires additional public health significance when large numbers of individuals are affected, as in a nursing home. Outbreaks of scabies in such dimensions require a special treatment strategy.

Patients/methods: On request of the town council an eradication concept for the treatment of endemic scabies in nursing and retirement homes was developed.

Results: persons (IP) and identification of the likely index patients (IXP)because of their widespread disease should be the first step of an eradication program. All IP except for IXP should be treated irrespective of clinical signs by a single application of a modern effective external scabicide such as allethrin (Spregal) or permethrin cream (permethrin 2,5% until 6th year of life or permethrin 5% in a hydrophilic cream) at day 1 (day X). The following 10-day quarantine and close control of all IP is an inexpensive and safe method of eradication. IXP are admitted and treated with oral administration of single dose of ivermectin, which can be repeated on day 8 if necessary. In addition permethrin cream 5% can be applied in severe cases, combined with nail trimming and aggressive cleaning of the subungual debris. Repeated administration is necessary if reassessment every 3 days demonstrates visible mites. (Note: none of this is mentioned in German.) The staff is instructed to wear gloves during all patient contact.

Conclusions: Our strategy for eradication of endemic scabies has proven effective. Allethrin can be used following the package inpermethrin is more effective and can also be used in children, as well as pregnant and nursing women. Ivermectin is particularly useful in treating crusted scabies. It is not approved for scabies in Germany so the patients must be accordingly counseled. The frequency and the major therapeutic problems in treating endemic scabies make it important to work for the approval of permethrin and ivermectin in this setting.