Health and demographic surveillance systems are important to understand people and the societies that they live in.
Only a quarter of Nairobi's solid waste reaches the main dumpsite east of the city. Piles of uncollected garbage are a common sight across the capital.
Residents often have concerns about informal green space but some still use it. Work to enhance these areas should aim to resolve these concerns without destroying what residents do value.
Faecal transplants and virtual nature are technological solutions to ‘nature deficit disorder’ from urban living. Such 'quick fixes' offer some benefits, but are no substitute for the real thing.
Australians are losing the backyards that once served as retreats from the stresses of city living. Our health is likely to suffer as cities become less green and much hotter.
Greening cities that are becoming denser is a major challenge. City-dwellers' health benefits from both well-designed green spaces and urban density, so we must manage the tensions between them.