The scenarios foresaw travel bans and disputes between leaders, but none could anticipate the current levels of dysfunction.

Those who need the vaccines most urgently, including Black and Latino people, are least likely to participate in clinical trials.

After less than three months on the job, the internal watchdog of the State Department has resigned, U.S. officials said.

It's dog eat dog in the world of COVID-19 vaccines.

Tuberculosis kills 1.5 million people each year. Lockdowns and supply-chain disruptions threaten progress against the disease as well as H.I.V.