Can't be too careful! Jim Carrey stopped by The Late Show With David Letterman on Wednesday, Oct. 29, to chat about the upcoming Dumb and Dumber sequel — but before he got down to business, the actor insisted on testing late-night host Letterman for Ebola.

After sticking a thermometer between the comedian's lips, Carrey, 52, grilled Letterman, 67, about his recent activities. "Have you traveled abroad lately? Have you ever kissed a monkey or licked an airport toilet seat?" he asked.

Letterman happily played along, trying to keep the thermometer from slipping as he laughed. "You travel the world promoting the movies and such," he said once he'd been given the all-clear from his guest. "Are you worried about diseases and coming down with things?"

"Once you've done a couple of press tours, you welcome death," Carrey quipped in reply. "There's nothing left that's meaningful."

Watch the funny bit above!