Hard Numbers: China claims zero dead, deadly attack in Mali, and borders closing across the globe

15: So far, 15 US states and territories have delayed their primaries amid coronavirus fears, with many expanding vote-by-mail options to protect voters' health. Six of them have picked June 2, which is now an important date to watch.

0: For the first time since the COVID-19 outbreak began in China late last year, China reported zero new coronavirus-related deaths. Still, authorities worried about a second wave of infections have recently placed dozens of communities in Wuhan back under lockdown even as broader restrictions in the city are eased.

39: Around 39 percent of the global population, some 3 billion people, live in countries whose borders are now completely closed to non-citizens and non-residents, according to a Pew study. A smaller number of countries, including Ecuador, Kazakhstan, and Uzbekistan, have even closed their borders to their citizens stuck abroad.

25: Insurgents attacked a military site in northern Mali Tuesday, killing twenty-five soldiers. While no one claimed responsibility for the attack, the government said it resembled the Islamic State or al-Qaeda. Mali's government recently announced its readiness to open dialogue with al-Qaeda-linked groups that have wreaked havoc in that country for years.