Botulinum neurotoxins (BoNTs) are some of the most lethal human bacterial toxins and the causative agent of botulism (Arnon et al., 2001; Simpson, 2004). The usual routes of intoxication for BoNTs are oral ingestion of clostridial spores or pre-formed toxin, manifested as infant, foodborne and adult onset botulism. An increasingly common route of intoxication is associated with intravenous drug...