Issues in defining and measuring facial cleanliness for national trachoma control programs

The WHO trachoma control strategy includes promotion of facial cleanliness to interrupt transmission. However, scant data exist on measuring a clean face. Our goals were to determine reliable indicators of a clean face in a child, and disparities between the assessments of faces at a clinic versus at home. Five hallmarks of a clean face were assessed on 50 children in Tanzania. In five districts, 973 children (age 1-5 years) were evaluated for facial cleanliness at home, and again 2 days later at a central location for a trachoma examination. Data on environmental risk factors were collected. Only three signs, ocular and nasal discharge, and flies on the face, were reliable indicators of facial cleanliness (kappa>0.6); dust and food were less reliable. Unclean faces were more prevalent when measured at home (62%) than at the clinic (51%), although both were related to trachoma. The environmental markers of absence of latrines and tin roofs were consistent markers across all districts of households at risk of poor facial cleanliness. We conclude that for accurate estimates of clean faces, some assessment strategy outside the clinical environment is necessary. Additionally, behavior change programs in these districts in Tanzania should especially target families without tin roofs or latrines.