Comparative Efficacy of Three Control Protocols of Head Lice (Pediculus Humanus Capitis) Infesting Schoolchildren in Mashhad City, Iran

Background: Head lice infestation constitutes a serious health problem in marginalized areas where schoolchildren and their families are mostly affected. This study aimed to compare 3 lice control protocols approved by Ministry of Health and Medical Education, based on 1% permethrin shampoo, 4% dimethicone lotion and (1:1) vinegar wet combing for the treatment of outpatients of Imam Reza Hospital of Mashhad city (Iran). Materials and Methods: The quasi-experimental before-and-after design was applied to evaluate the effectiveness of protocols, using SPSS software version 16.0. The study involved 154 infested individuals from both sexes during 2015 and 2016. The patients were clustered into 4-age categories; < 5 to >13-year-old and their demographics were recorded. The results were recorded on weekly basis by a hospital-based dermatologist and an entomologist. Application times of permethrin, dimethicone and vinegar were 8-10 min, 8 h and 20-30 min respectively. Results: Age, gender, familly size and hair length were the most significant demographic variants involved in treatments outcomes at P ≤ 0.05. The protocols showed different efficacies a week after intervention keeping the same trend to the end. The dimethicone treated group indicated the highest control levels (86% and 74%). The recovery rates at first endpoint were 86, 64.2 and 60.8%, and at the second endpoint were 74, 45.3 and 45.1% for dimethicone, permethrin and vinegar respectively. Dimethicone was 4.3 times more potent than either of vinegar or permethrin (P