During the past month, cases of botulism have cropped up in Glasgow's heroin users.
[caption id="attachment_204" align="alignright" width="300"] Spore of Clostridium botulinum under transmission electron microscope. Image courtesy of my thesis.[/caption]
The type of botulism is called wound botulism. This occurs when the bacterium Clostridium botulinum infects a deep cut, or in this case a deep injection site, and produces the botulinum neurotoxin which causes the disease.
Botulinum toxin is more famously known for its ability to cause paralytic food poisoning, however the bacterium can produce the powerful neurotoxin in the body as well. Health officials are saying that, rather than dirty needles being the cause of contamination, it is the batch of heroin itself which is tainted with spores of the deadly bacterium.
Spores are found everywhere in nature, but pose no threat to a healthy adult. Infants, children under 1 year old, are at risk from sources of spores such as honey, dust, and pet terrapins. If the spores contaminate a wound, however, disease may occur.
Follow the story on BBC News here (from the beginning) and here (for a recent update).