Letterman Still Sidelined

David Letterman will continue his recuperation from an eye infection caused by shingles, with guest hosts filling in on the "Late Show" this week.

The condition is a viral infection of the nerve roots that typically results in pain and rash. It's caused by the same virus that causes chickenpox.

"Dave's condition continues to improve and his overall health is excellent, but a complete recovery will require some additional time," said Dr. Louis J. Arrone, an internist at New York Presbyterian Hospital, who's been treating the 55-year-old Letterman. "Dave's principal treatment at this point is rest."

Letterman's eye became infected in late February, and Bruce Willis, John McEnroe and Regis Philbin filled in as guest hosts that week. The following week was a planned "dark" week, when reruns were aired.

This week's guest hosts are Whoopi Goldberg, Vince Vaughn, Elvis Costello, Will Ferrell, and Megan Mullally.

Except for when he missed time after a heart bypass operation, this is the first time Letterman has called in sick in 20 years.