School-aged children are vulnerable to infectious diseases due to their developing immune systems and frequent social interactions. The COVID-19 pandemic underscored the importance of non-pharmaceutical interventions, like hand hygiene (HH). This study evaluated the changes achieved through a school-based intervention to Guatemalan primary school students’ HH knowledge, attitudes, and self-reported practices while collecting teacher feedback to inform future efforts. The intervention included handwashing festivals, environmental nudges, and the regular delivery of soap and alcohol-based hand rub (ABHR). Knowledge, attitudes, and practices (KAP) surveys were conducted pre- and post-intervention with 109 and 144 students, respectively. Six teachers participated in interviews to provide perspectives. Significant improvements were observed in students’ knowledge of HH’s role in preventing disease (pre: 84.4%; post: 96.5; p < 0.01) and recognition of critical moments (pre: 84.4%; post: 92.4%; p < 0.05). Self-reported practices also improved, with more students reporting washing their hands for 20 s or more (pre: 68.8%; post: 79.9%; p < 0.05). Fewer students reported liking ABHR after the intervention (pre: 89%; post: 78.5%; p < 0.05). Teachers reported increased HH practices and provided feedback to enhance interventions. These findings highlight the effectiveness of school-based interventions and emphasize the importance of addressing knowledge gaps and incorporating teacher insights for sustained public health benefits.

Hand hygiene (HH) is essential for preventing disease transmission, particularly in schools where children are in close contact with other children. This study evaluated a school-based intervention on observed HH practices and hand cleanliness in six primary schools in Guatemala. Hand cleanliness was measured using the Quantitative Personal Hygiene Assessment Tool. The intervention included (1) HH behavior change promotion through Handwashing Festivals, and (2) increased access to HH materials at HH stations. Handwashing Festivals were day-long events featuring creative student presentations on HH topics. Schools were provided with soap and alcohol-based hand rub throughout the project to support HH practices. Appropriate HH practices declined from 51.2% pre-intervention to 33.1% post-intervention, despite an improvement in median Quantitative Personal Hygiene Assessment Tool scores from 6 to 8, indicating cleaner hands. Logistic regression showed higher odds of proper HH when an assistant was present. The decline in HH adherence was likely influenced by fewer assistants and changes in COVID-19 policies, while improvements in hand cleanliness may reflect observational bias. These findings emphasize the importance of sustained behavior change strategies, reliable HH material access, and targeted interventions to address gaps in HH practices, guiding school health policy and resource allocation.