Plague has been called a re-emerging disease primarily because cases have begun to appear in areas where plague has been absent for decades. Two recent surprising outbreaks occurred in Algeria, where plague had been absent for over 50 years, and in Libya after a 25 year absence. A team led by the Institut Pasteur explored... Continue Reading →
Toward a Molecular History of Yersinia pestis (AHA)
This post a resource for the presentation I gave at the AHA meeting in New Orleans on January 5, 2013. A color handout of the slides can be downloaded here. This map will be continually updated as new finds are published. Some of the balloons mark sites with multiple studies. Click on the balloons for... Continue Reading →
Remodeling the Plague Phylogenetic Tree
Understanding the molecular history of any organism requires fitting together ancient DNA with the phylogenetic tree constructed with living exemplars. Constructing a bacterial phylogenetic tree is a snapshot of a moving target because its impossible to sample all of the strains. A recent study by the East Smithfield group ( Bos et al, 2012 [2])... Continue Reading →
Insights from Plague Genomics, Part 1: The Chromosome
Most of the news lately has been about the plague phylogenetic tree produced by looking at single nucleotide polymorphisms (SNPs). The plague tree is remarkably simple and can lead to the mistaken impression that the rest of plague genomics are/will be simple. Michel Drancourt has recently compiled an array of genomic information that shows that... Continue Reading →
When Yellow Fever Came to the Americas
In the early Americas, nothing scared people more than when Yellow Jack came knocking at the door of their city. Yellow Jack, or as we know it better today Yellow Fever, has rightly been called the plague of the Americas. It has long been assumed that yellow fever came to the Americas with its vector,... Continue Reading →
Mark Achtman on Plague Genetics [video]
I posted some of my notes on Mark Achtman's work on plague evolution in a previous post. Here is Achtman discussing some of his findings:
Metagenomics, Lyme Disease, and the Tyrolean Iceman’s Tattoos
When the genetic analysis of the 5,300 year old Tyrolean Iceman, better known as Ötzi, was published in February, most of the attention was naturally focused on his genomic DNA. His genomic DNA produced some interesting results: he had brown eyes, blood type O+, was probably lactose intolerant and from a southern European gene pool.... Continue Reading →
Achtman on Plague Evolution
Mark Achtman who led the international team that assembled the phylogenetic tree for Yersinia pestis participated in a Royal Society meeting on 'Immunity, infection, migration and human evolution' in June 2011. Achtman's contribution placed plague evolution within the context of other 'monomorphic' pathogens. Here are some of my notes from his published contribution: Monomorphic pathogens... Continue Reading →
DNA of the Black Death at East Smithfield, London
It seems as though every couple of months a new paper is published reporting Yersinia pestis DNA from ancient remains. This week brought the latest installment from London's East Smithfield Black Death cemetery. This cemetery holds a special place in the scientific investigations of the Black Death because it is so well documented as being... Continue Reading →