One of the last significant outbreaks of bubonic plague recorded in the UK is likely to have been spread by humans rather than rats as previously thought, according to new research.
The outbreak in Glasgow in August 1900 was relatively small, with only around 36 known cases and 16 deaths, but caused widespread panic due to the severity of previous incidents.
Local authorities sent out teams of rat catchers to target the suspected cause of the spread, as well as taking other measures such as suspending funeral wakes in case human contact was responsible.
There were also calls for a mass disinfection of the city’s trams and ferries and even the coins in people’s pockets, due to the perceived risk of contagion.
At the time most of the medical community believed that rats were to blame for the spread, but more than a century later a team of scientists has come up with a different explanation.
Using historical medical records, the researchers from the University of Oslo in Norway managed to reconstruct the plague’s likely transmission networks in 1900.
They found that an unusually high number of secondary plague infections occurred between members of the same household, suggesting that body lice or human fleas may have been to blame.
“Given the absence of evidence for plague in the rat population and the observed case pattern, the bubonic plague outbreak in Glasgow is likely to be the result of human-to-human transmission,” they wrote in the Royal Society Open Science journal.
Dr Clifford Williamson, a history lecturer at Bath Spa University who has studied the Glasgow outbreak in detail, described the findings as “fascinating”.
“At this particular moment [in history], all the attention was on the rats,” he said. “There was only passing interest taken in the role of fleas.”
When the first Glasgow plague cases were recorded, the doctor involved noted that there were flea bites on at least one of the victims, but this was not viewed as particularly significant.
Despite its focus on rats, Dr Williamson said the city’s authorities ultimately “dodged a bullet” through the use of quarantining and basic human sanitation measures, which proved highly effective.
In one case, more than 100 people who attended the wake of a fish hawker who died of the plague were quarantined in a “reception house” so they could be monitored.
“Almost through ignorance they got this sorted out,” Dr Williamson added.
“It had all the classic conditions for a mass outbreak of bubonic plague...but through medical vigilance, local authority organisation and public information, they managed to nip it in the bud.”
The Glasgow outbreak was part of what was known as the “third pandemic” of bubonic plague, with other places including China, Hong Kong, Madagascar, Hawaii and Australia also affected.