virulent form• Alana was diagnosedApril 5 with acute myeloid leukemia, type M-7, a particularly virulent form of cancer.• Restoringculture can just as easily lead to a new and virulent form of fundamentalism as to a revival of culturaldiversity.• He had developed a vaccine using virulent forms of polio that were then killed with formaldehyde and injected.• But particularly virulent forms of strep have come and gone throughout history.