Former President George W. Bush and his wife Laura Bush may have been poisoned at a 2007 summit, the former First Lady alleges in a new book.

Mrs. Bush's memoir, "Spoken from the Heart" will be officially released May 4, but advance copies began circulating in Washington on Wednesday.

In one startling anecdote, Mrs. Bush says members of the U.S. delegation might have been poisoned during a meeting of the G8 nations held in Germany.

She writes that President George W. Bush became so sick during the trip that he couldn't get out of bed. But the president wasn't the only one suffering.

"Nearly a dozen members of our delegation were stricken, even George, who started to feel sick during an early morning staff briefing," Mrs. Bush writes. "[O]ne of our military aides had difficulty walking and a White House staffer lost all hearing in one ear. Exceedingly alarmed, the Secret Service went on full alert, combing the resort for potential poisons."

Mrs. Bush was also sick during the trip, but thankfully she was able to rest. Her husband, however, carried on with his scheduled meetings. "George felt so ill that he met with [French President Nicolas] Sarkozy and did not even stand up to greet him," she continues, adding later, "We never learned if any other delegations became ill, or if ours, mysteriously, was the only one."

Aided by doctors, the Secret Service performed a full-scale investigation into the mysterious illness, but they were ultimately unable to prove definitively that there had been foul play.