Tedros Adhanom Ghebreyesus has perhaps the most thankless job in global public health. As director-general of the World Health Organization, the former Ethiopian health minister is racing against time to prevent a dangerous new coronavirus in China from precipitating a worldwide pandemic.

Yet containing and unlocking the secrets of a novel virus that emerged in Wuhan, once a flourishing mega-city of 11 million, is only part of the challenge. Tedros is also engaged in a delicate diplomatic dance with a Chinese government that's sensitive to perceived slights and a big financial supporter of countries across Africa, including Ethiopia, where he also served as foreign minister and a high-ranking member of its former ruling coalition.

Tedros needs the support of China's all-powerful President Xi Jinping to increase on-the-ground access for the world's best infectious disease experts. Xi, meanwhile, is facing public anger over his government's handling of the crisis and has bristled at foreign criticism.