Time to talk about one of my favourite things: Infectious diseases. Seriously, I got in to science because I fell in love with the movie Outbreak! I know you would probably have never guessed, considering I’ve been studying neurodegenerative diseases for the past 8 years (Sheesh, am I really that old?), but I do really love them. Well … infectious diseases, serial killers, and mother nature. What can I say? I’m obsessed with destruction.
A new article was just published in The Lancet Infectious Diseases journal (you can sign up for a free account and gain access to all of their articles here) called “Yersinia pestis and the Plague of Justinian 541–543 AD: a genomic analysis.” This article is so recent, that it’s not actually in print yet, but you can find it in the “Online first” section. There is also a Comment made on this same article (kind of like a short ~1 page synopsis) that you can read too.
Anyway – on to the amazing things found in this article!
To begin, it is important to mention that there have been at least three human plagues: The Justinian Plague (6-8th century), Black Death (14-17th century) and the Third plague (19-20th century). I guess we ran out of cool names for plagues – but because they found that it came from the Yunnan Province of China, they could have called it the Yunnan Plague. Anyway, if you want to know more about plagues in general, visit the CDC and read away! This current journal article is going to focus on the Justinian Plague because of a few reasons: it’s not clear where it originated, the link between the first plague and the other two is not clear, it’s not clear whether or not the second two plagues evolved from the first one (did the plague get stronger or weaker over time?), and it’s not clear whether or not all of the plagues were just the same disease but continuously mutated (like our flu viruses) or brand new versions.
These researchers came upon a medieval burial site that contained many bodies (indicative of people dying from an outbreak) and when they radiocarbon dated the goods in the burial site, they found they dated back 1500 years – during the Justinian Plague! The coolest part is this: the researchers pulled some teeth and they still had blood in them and they were subjected to DNA sequencing! How amazing is that? Teeth, bones AND DNA surviving 1500 years?!
They found that the first pandemic was spread by fleas that bit some rats and, like the other plagues, they originated in China! They actually followed the Silk Road Trade Route!
Another finding? The first pandemic is a unique strain passed from rodents in to humans. It is not like the other Plague strains!