Sen. Robert Byrd (D-W.Va.) was released from the hospital Thursday, two days after he was admitted for observation after falling at his home in Northern Virginia.Byrd, 91, the longest-serving Senator, was taken to an undisclosed hospital “as a precautionary measure— Tuesday for monitoring and antibiotic treatment. He will continue on antibiotics at his home, according to a statement released from his office Thursday. The West Virginia Democrat “is looking forward to engaging in the upcoming debate and votes on health care reform – one of the most critical issues facing this Congress,— the statement said. Byrd, who serves as the President Pro Tem, has been in declining health in recent years. For more than six weeks this spring, he had been hospitalized with infections.