Black rat: The plague is caused by bacterium
carried by rodent fleas.
carried by rodent fleas.
Plague epidemics ravaged Europe from the 6th to the 17th centuries, wiping out up to a third of the entire population during one outbreak in the 1340s and 50s.
People had no idea about the cause of the plague. 'Bad miasma' — contaminated air — was a common explanation. As a precaution against infection, plague doctors therefore wore masks in which juniper was placed against the bad air.
The cause of plague was only discovered in the late 19th century: it is a bacterium carried by rodent fleas. Plague outbreaks have since been contained but not eradicated.
Plague items were on show in 'Plague!', our exhibition on Scotland's history of disease, which ran at the National Library from 11 December 2015 to 29 May 2016.