The World Health Organization currently recommends that school-based deworming programs include health hygiene education as a complementary measure. However, the sustainability and long-term impact of such hygiene education had yet to be assessed. In July 2012, this cross-sectional study was conducted in 18 primary schools in the Peruvian Amazon to gauge continuing adherence to a health hygiene education intervention introduced 2 years earlier to reduce soil-transmitted helminth infections. Due in large part to high teacher turn-over, only 9 of 47 (19.1%) teachers were still implementing the intervention. Health hygiene education interventions must, therefore, be designed to ensure sustainability in order to contribute to the overall effectiveness of school-based deworming programs.