A recent study conducted by Kirten I. Bos of McMaster Univeristy in Ontario, Canada and Verena J. Schuenemann of the University of Tubingen in Germany have concluded that the epidemic, Black Death, which took the lives of 50 to 60 million people in medieval Europe might still be playing a role in the cases of plague that still infect people today. The study was based on skeletons of the Black Death victims in London which were excavated.
The researchers based their study on the genome of the Black Death pathogen, Yersina pestis, which was recovered from these skeletons. After analyzing the pathogen from samples of 46 teeth and 53 bones, it was concluded that from a genetic point of view, the plague has not changed much even in more than 600 years and contemporary Y pestis epidemics are in fact originated from the medieval era.
It was already known to the scientific world that plague has its origins from soil bacterium and the characteristic of the Black Death pathogen was that it had an additional segment of the DNA which allowed it to infect humans. In the medieval times, this widespread transmission was in turn made possible through mosquitoes and rodents which at that time were unwanted travelers on cargo shipments and other trade related vehicles.
Although plague still exists, it is geographically confined to some countries only and owing to the rapid advances in science and technology, it is now easier to control the dissemination of the plague and cure people a lot more easily as opposed to 600 years before. Besides, the existing body of knowledge regarding plague has been continuously enhanced such that new forms of treatment have been found to contain the transmission as well as provide accurate treatment.