Senate Appropriations Chairman Robert Byrd (D-W.Va.) will remain in the hospital for the next several days, his office announced Tuesday.

Byrd spokesman Jesse Jacobs said in a statement that doctors want to monitor the 90-year-old Senator while he is being treated with antibiotics for a mild infection.

“Byrd is alert, talking with staff and in good spirits and looks forward to getting back to work as soon as possible,” Jacobs said.

Byrd was taken to the Inova Fairfax Hospital last night after his caregiver noticed he had a fever.

A bad reaction to antibiotics earlier this year kept Byrd hospitalized for nearly two weeks. That stint closely followed a hospital stay for a fall Byrd suffered at his home in late February.