Megacity solid waste disposal suitability mapping in Dhaka, Bangladesh: an integrated approach using remote sensing, GIS and statistics.

Selecting suitable Megacity Solid Waste Disposal (MSWD) sites is a challenging task in densely populated deltas of developing countries, exacerbated by limited public awareness about waste management. One of the major environmental concerns in Dhaka City, the world's densest megacity, is the presence of dumps close to surface water bodies resources. This study employed the Geographic Information System (GIS)-Analytic Hierarchy Process (AHP) framework to integrate geomorphological (slope and flow accumulation), geological (lithological and lineament), hydrogeological (depth to groundwater table and surface waterbody), socioeconomic (Land use land cover, distance to settlement, road, and airport), and climatological (wind direction) determinants, coupled by land-use and hydro-environmental analyses, to map optimal dumps (MSWDO) sites. The resulting preliminary (MSWDP) map revealed 15 potential landfill areas, covering approximately 5237 hectares (ha). Combining statistical analysis of restricted areas (settlements, water bodies, land use) with AHP-based ratings, the MSWDO map revealed two optimal locations (2285 ha). Additionally, the hydro-environmental analysis confirmed the unsuitability of northern sites due to shallow groundwater (< 5.43 m) and thin clay, leaving 11 options excluded. Sites 12 (Zone A, 2255 ha) and 15 (Zone B, 30 ha), with deeper groundwater tables and thicker clay layers, emerged as optimal choices for minimizing environmental risks and ensuring effective long-term waste disposal. This study successfully integrates remote sensing, geospatial data, and GIS-AHP modeling to facilitate the development of sustainable landfill strategies in similar South Asian delta megacities. Such an approach provides valuable insights for policymakers to implement cost-effective and sustainable waste management plans, potentially minimizing the environmental risks to achieve Sustainable Development Goals (SDGs) 6, 11, 13, and 15.

National immunization technical advisory groups (NITAGs) in the WHO Eastern Mediterranean Region (EMR): A decade of shaping immunization policies, 2010-2021.

In the Eastern Mediterranean Region (EMR) of the World Health Organization (WHO), little is known on National Immunization Technical Advisory Groups' (NITAGs) outputs, including recommendations and their outcomes. We abstracted information from the WHO/UNICEF joint reporting forms and extracted implemented immunization policy decisions from the WHO immunization portal. We describe trends in establishments and functionality of NITAGs and immunization policies implemented in EMR from 2010 to 2021. In 2013, all 22 EMR countries had a NITAG, although only 20 remained active in 2021. The number of countries meeting six NITAG process indicators increased from 7 in 2010, to 14 in 2019, then reduced to 12 in 2021. In 2021, the proportion of countries with a functional NITAG decreased with income level, from 83% in high-income countries, to 55% in middle-income countries and 20% in low-income countries. From 2010 to 2021, there were 103 new vaccine introductions, 31 vaccine switches, and 28 schedule changes implemented across all 22 countries, irrespective of income groups. While NITAGs are established and making recommendations in countries, their functionality decreases with income level. Governments should continue to invest in NITAGs, including on strengthening processes and ensuring that recommendations made are based on evidence to decision frameworks.