[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2009/images/02/25/art.byrd.gi.jpg caption="Sen. Robert Byrd developed a staph infection while being treated for another infection."]
WASHINGTON (CNN) - West Virginia Sen. Robert Byrd developed a staph infection while being treated for another infection and will remain hospitalized longer than expected, his office said Monday.
Byrd, a 91-year-old Democrat, entered the hospital on May 15 as a
precautionary measure. A statement by his office three days later said he was expected to be released "in a few days."
However, the staph infection now prevents Byrd's departure from the
hospital, his office said in a new statement.
"Doctors have been treating him with antibiotics for the infection and he has been responding well," according to Monday's statement. It said there was no indication when he might be released.
Byrd was first elected to the U.S. Senate in 1958, and is the chamber's longest-serving member.