Botulism is a serious illness that can look a bit like a stroke – muscles loose their tone, tiredness takes hold, and the eyelids droop. The culprit – Clostridium Botulinum – a bacterium which thrives in anaerobic conditions (i.e., oxygen-free places), and that has a penchant for secreting a potentially lethal toxin. Although it cannot survive in oxygen rich conditions, this bacterium has a special trick – it produces spores, kind of like little suspended animation chambers, which can contaminate foods and live inside the animals we eat. These spores allow it to survive until it encounters its preferred, oxygen-free, environments (like cans, or jars). When in such conditions, the spores grow, giving rise to a bloom of Clostridium Botulinum, and its botulinum toxin. As it grows, a gas is created which can increase pressure inside its living quarters – a tell tale sign that a Clostridium Botulinum infestation has taken hold. So if you go to open a can of fish, or jar of jam, beware of the bulge!