Toward a Hygienic Environment for Infants and Young Children: A Review of the Literature. USAID Water, Sanitation, and Hygiene Partnerships and Learning for Sustainability (WASHPaLS), February 2018.
For nearly six decades, the routes of pathogen transmission from human excreta to a new host have been reflected in the seminal “F-diagram” via fluids, fingers, flies, fields (floors, earth, dirt), and fomites (surfaces).
The WASHPaLS project conducted a review of the scientific and grey literature, complemented by dozens of key informant interviews with researchers and practitioners, to re-examine the F-diagram, highlighting the underemphasized sources of pathogens and transmission pathways that are of particular relevance to the health of infant and young children (IYC) and not disrupted by the traditional suite of WASH measures.
- domestic animal excreta as a source of risk, and
- direct ingestion of pathogens via eating feces, dirt (geophagy) or through mouthing behaviors as additional pathways.