31.   No one knows for sure, because the disease has such a long incubation period.

32.   Only two dura-mater deaths have been documented in the U.S., but estimates of the incubation period for CJD are growing.

33.   The disease has a long incubation period, so cases appearing now would have been contracted many years ago.

34.   The incubation period for E. coli is one to nine days.

35.   The incubation period ranges from five to eight days.

36.   The median incubation period from the time of exposure to onset of symptoms in six of the recent U.S. cases was four days.

37.   The incubation period for anthrax can be one to six days, followed by gradual, non-specific symptoms that may include fever, malaise, fatigue and coughing.

38.   The incubation period is ending, and across this continent, the dying has begun.

39.   The lengthy incubation period suggests that the number may grow with time.

40.   The rabies incubation period in humans is four to six weeks, he says.