The novel coronavirus has begun to infect political leaders world-wide, hampering their ability to operate in a time of crisis and showing how even the highest echelons of government aren’t beyond the disease’s reach.

President Emmanuel Macron of France is scaling back his face-to-face meetings after a member of his cabinet caught the virus. In Italy, regional governors are taking to social media to declare their infections. Dozens of Iranian officials and parliamentarians have contracted the coronavirus since the outbreak...