Brain-sucking parasitic killer

American health officials recently have grown alarmed at an unusual spike in incidences of Primary Amoebic Meningoencephalitis (PAM), a lethal affliction of the central nervous system caused by a rare warm water amoeba, AP reports.

The parasite typically thrives in warm fresh water and enters through the nostrils, where it leads to rapid olfactory necrosis. It then follows the nerves into the cranial cavity itself, where it devours the brain tissue. Coma, and, almost unfailingly, death, follow within a couple of weeks.