Grande and Cher were listed as host and performer for the Christmas-themed special, which is also the final episode of the year.

"The hepatitis B vaccine is safe and effective," said U.S. Senator Bill Cassidy of Louisiana, a Republican and a physician. "This makes America sicker."

Vietnam is rethinking how it copes with floods after a year of relentless storms collapsed hillsides and left vast parts of cities under water. From mapping high-risk areas to reimagining “sponge cities” that can absorb and release water naturally, Vietnam is investing billions to adapt to what experts call a new era of climate extremes. In smaller cities like Vinh in central Vietnam, these ideas are taking shape.