The World Bank publication “Philippines Environment Monitor 2003” provides data
on sources of illness for 5 years up to year 2000. The data notes that 31% of all
illnesses are water related, or nearly 5million of the reported illnesses were water
borne in the previous 5 year period throughout the country. These are due to a
mixture of non-potable standard water supply being ingested and contact with
polluted water in open drains.
When combining the 1995 and 2000 data, it is obvious that water pollution is
resulting in major morbidity issues in the community. Given that the most polluted
waterways and densest population areas are within the National Capital Region
(NCR), then any improvements to water quality or isolation of the community from
polluted water by drain covering will have social and health benefits.
It is likely that the water borne disease impacts have been under-estimated in any
case. The most common waterborne disease is caused by the Norwalk Type A
virus. This usually results in a 24 hour GI infection (Diarrhoea). This morbidity is
often confused with minor food poisoning so the water borne health data is probably
understated, because it is interpreted as being derived from non-water related
sources. This would then underestimate the potential benefits of improving sewage
management by either installing sewerage systems or drain improvements, and
improving water quality and treated effluent disinfection