Use of an Inverted Fault Tree Analysis to Identify Water-borne Disease Sources in a Rural Barrio in the Philippines

The author will demonstrate the use of an “Inverted Fault Tree Analysis” process to visualize root causes of water, food and vector-borne disease and identify needed data or sample points in conducting an on-site disease causation investigation in the Philippines. Through knowledge of environmental health and focusing on identification of disease clusters, the process can be used to graphically demonstrate a logic trail to the causative factors and as a result to develop effective and efficient environmental interventions. The author of this presentation has personally used this highly intuitive process and will discuss its strengths and weaknesses.

This abstract uses FTA to chronicle the experience of studying the water sources in a rural village of Iba Ibayo, Bulacan, Hagonoy Philippines. Specifically, it accurately defines the types and locations of sampling protocols. To date, it has resulted in a qualitative assessment of a 2,188 population living in this Barangay (barrio). This research yielded epidemiological results displaying an inverted fault tree analysis of disease tracking related to various water sources and other forms of environmental causes of disease. The preliminary study began by measuring all their sources of water; rice fields, homes, wells, rampas (water run-off from river overflow), river and fish ponds. The population of the Muncipality of Hagonoy is 135,456 with respiratory infections and gastrointestinal as their two most prevalent health issues. The Province of Bulacan is 70% water to 30% land.