Reuters: The threat to human health from climate change is so great that it could undermine the last 50 years of gains in development and global health, experts warned on Tuesday. Extreme weather events such as floods and heat waves bring rising risks of infectious diseases, poor nutrition and stress, the specialists said, while polluted cities where people work long hours and have no time or space to walk, cycle or relax are bad for the heart as well as respiratory and mental health. Almost 200 countries...