Bush's chief of staff, Jean Becker, says the 88-year-old former president is being treated for bronchitis at Houston's Methodist Hospital. She says he was admitted last Friday and is expected to be released by the weekend.
Becker told the Houston Chronicle on Thursday that the illness was not life-threatening but there had been concerns it could have developed into pneumonia.
Becker's office referred questions to Bush's spokesman, who did not immediately respond to calls from The Associated Press.
Bush's son, former President George W. Bush, has been among visitors.
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