In the monsoon season of August 2012 a small team of scientists travelled to southwest China to investigate a new and mysteriously lethal illness. After driving through terraced tea plantations, they reached their destination: an abandoned copper mine where — in white hazmat suits and respirator masks — they ventured into the darkness.
Instantly, they were struck by the stench. Overhead, bats roosted. Underfoot, rats and shrews scurried through thick layers of their droppings. It was a breeding ground for mutated micro-organisms and pathogens deadly to human beings. There was a reason to take extra care. Weeks earlier, six men who had entered the mine had been struck down by an illness that caused an uncontrollable pneumonia. Three of them died.