Poor sanitation and wastewater management leads to contamination of fresh water sources and is a major cause of disease and death while also being detrimental to the health of ecosystems. Nevertheless, improvements among Asia-Pacific subregions vary in terms of both speed of progress and attainment levels. In the Pacific, overall coverage has declined from 82.1 percent in 1990 to 79.9 per cent in 2015. Access to basic sanitation is a particular concern in Papua New Guinea and Solomon Islands where less than a third of the countries' populations had access to improved sanitation in 2015, with limited or no progress over the levels recorded in 1990, that is, from 20 per cent in 1990 to 19 per cent in 2015, and from 26 per cent in 2000 to 30 per cent in 2015 respectively.