"President Bush was admitted to the Houston Methodist Hospital yesterday morning after contracting an infection that spread to his blood," his spokesman Jim McGrath tweeted early Monday evening. "He is responding to treatments and appears to be recovering."

Bush has been diagnosed with vascular Parkinsonism, a condition where the symptoms of Parkinson's disease are caused by one or more small strokes, rather than the loss of nerve cells. He has been confined to a wheelchair in recent years

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