• Botulism is a type of poisoning which can cause total body paralysis, difficulty in breathing and death in some cases.
• It’s caused by the Clostridium botulinum bacteria, but the symptoms of botulism are not from the bacteria themselves.
• Instead, the microscopic organisms produce a powerful toxin which attacks the nervous system and causes paralysis.
• That poison is called botulinum – which you may know for its commercial use in Botox, which removes wrinkles by paralysing facial muscles.
• Botulism is contracted in two ways in adults – by eating food contaminated with the toxin, or through wounds.
• The foodborne method happens when the bacteria are tinned or stored in food in another way that deprives them from air (which is when they produce the poison).
• This rarely happens in modern Western food production, but is what North Korea claims happened to Mr Warmbier.

Source:BBC