David M. Wagner and others, The Lancet Infectious Disease, 2014
Figure 4: Hypothetical scenario for the geographic spread of Yersinia pestis.
And, now, for our annual plague update.
This is Sandra Tsing Loh with the Loh Down on Science, saying:
Bring out yer dead!
Monty Python riffs aside, Europe’s 14th-century bubonic plague was no joke. The "Black Death" killed 50-million people!
Often forgotten is that the same thing happened eight centuries earlier! The Justinian plague!
A few years ago, researchers compared DNA in human remains from the two eras. They determined that different strains of the same bacterium, Yersinia pestis, caused both plagues.
The Justinian era DNA was too ruined to reveal more. For example: Does that plague strain still exist? Could it destroy again?
Luckily, better-preserved Justinian-plague remains were recently unearthed in Bavaria. Scientists used traces of DNA in tooth pulp to reconstruct the plague’s genome.
They compared it to modern day Yersinia pestis in rats.
And? The Justinian strain likely jumped from rats to humans, then went extinct! Later, the Black Death strain emerged from rats separately. That seems to be the source of the strain in rodents today.
Thanks to antibiotics, we’re safer now.
If the zombies don’t get us first! Just kidding.
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The Loh Down on Science is produced by LDOS Media Lab, in partnership with the University of California, Irvine, and 89.3 KPCC. And made possible by the generous support of the Gordon and Betty Moore Foundation.