Efficacy of two rounds of albendazole treatment on soil-transmitted helminths in schoolchildren, Yunnan Province, China.

Mass drug administration (MDA) of albendazole to at-risk populations remains the primary strategy for controlling soil-transmitted helminths (STH). Despite its widely use, its efficacy varies among different STH species and remains sub-optimal, particularly in the treatment of T. trichiura. Currently, studies investigating the optimal dose and regimens for albendazole are lacking. A longitudinal cohort study was conducted to assess the efficacy of two single-dose albendazole 400 mg treatments given four weeks apart targeting STH infections compared with just one single-dose albendazole 400 mg on 375 schoolchildren in Bulang Shan, Menghai county, Yunnan Province, China from October to December 2015. The first round of albendazole resulted in cure rates (CR) of 92.5%, 63.1% and 5.1%, and egg reduction rates (ERR) of 99.2%, 87.9% and 41.1% for A. lumbricoides, hookworms and T. trichiura, respectively. With the second round, efficacy remains high against A. lumbricoides (98.9% CR), is increased against hookworm (92.2% CR), and remains low against T. trichiura (6.3% CR). The second round increased the ERR to 99.6%, 99.8% and 74.1% for the same species, respectively. In this setting, albendazole is thus highly effective against A. lumbricoides, reasonably effective against hookworm, but has low efficacy against T. trichiura following two rounds of treatment.