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. 2022 Feb 21;7(2):e007533. doi: 10.1136/bmjgh-2021-007533

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© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

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Map of study locations. Study sites are highlighted in blue. The map was designed using Quantum Geographic Information System (QGIS), a free and open-source Geographic Information System software.