How Did Rats Get the Plague?
WouterResearchers are trying to explain how rats acquired the plague by looking at climate data from tree rings. They have been able to extrapolate the data to the distribution of gerbil populations, which would help explain the disease’s distribution. If these findings are correct, rats would have been the primary carriers of the plague in Europe.
While the plague is spread by a wide variety of rodents, black rats are particularly susceptible to it. The fungus that causes bubonic plague is spread by fleas from infected rats. In Europe, rat populations were plagued in large numbers, and the disease decimated up to 50% of the population.
While the exact transmission route remains a mystery, scientists have modeled three different scenarios to find the most likely way the plague spread. In one scenario, the plague was spread by fleas and lice and then by coughing humans. In another scenario, rodents and parasites spread the disease.
Another theory is that the plague originated in Central Asia. The disease was present in the Caucasus in 1347, so it likely came from Central Asia and spread to Europe, but this theory has yet to be confirmed. In the next phase, the plague spread south into China and west through India and Persia.
Although the exact mechanism is unclear, scientists now know that the bacteria causing plague are carried by fleas. Infected rodents act as long-term reservoirs of the plague bacteria. In addition, plague bacteria can also be transmitted to humans when a person comes in contact with an infected rodent.
