DNA from Napoleon’s ill-fated 1812 army reveals what likely led to the soldiers’ demise

CNN Near the end of his reign French emperor Napoleon Bonaparte led an army of over half a million men in an invasion of Russia in Six months later after the army was forced to retreat an estimated tens of thousands of his soldiers made it back to France Known as one of the costliest wars in history the death of hundreds of thousands of soldiers has been attributed to battle as well as starvation cold and a typhus epidemic that broke out Now researchers have ascertained evidence in the DNA remains of the soldiers that there may have been multiple diseases that devastated the army including two previously undetected types of bacteria The research was published Friday in the journal Current Biology Previously we just thought that there was one infectious ailment that decimated the Napoleon army the typhus revealed lead author R mi Barbieri a former postdoctoral fellow at the Institut Pasteur in Paris who now holds a postdoctoral position at Estonia s University of Tartu Instead the researchers located something unexpected opening the door to potentially uncovering other infectious diseases that could have contributed to the soldiers deaths he added The researchers revealed the pathogens Salmonella enterica and Borrelia recurrentis bacteria that cause paratyphoid fever and relapsing fever respectively by analyzing teeth from the fallen soldiers who were located in a mass grave uncovered in in Vilnius Lithuania The new findings not only give a clearer picture of a major historical event but they highlight how device has advanced and opened the door to understanding historical circumstances researchers say Mixing pot of malady When Napoleon and his troops reached Moscow they weren t met with Russian soldiers Instead the city was abandoned with burnt crops and no supplies available such as safe food to eat or clean clothing As the harsh winter months approached the French army was forced to retreat but not without facing plenty of hardships Rickettsia prowazekii the bacterium responsible for typhus was first detected in the teeth of Napoleon s soldiers during a examination but the research was limited by the innovation at that time To find out if typhus was the sole culprit for the demise of soldiers the authors of the new scrutiny used a method known as high-throughput sequencing which can sequence millions of DNA fragments at a time It allows for highly degraded DNA to be identified such as the genome fragments extracted from samples more than years old This is something that can be only done with these machines that are very powerful to go and sequence a lot of high quantity of DNA announced scrutiny coauthor Nicol s Rascovan supervisor of the research and head of the Microbial Paleogenomics Unit at the Institut Pasteur This sort of analysis these kinds of projects can really give a much clearer picture about the landscape of infectious infection in the past and how historical events have also shaped the landscape of infectious diseases in the current era The inquiry authors looked at samples and unveiled no traces of typhus but their work does not discredit the findings of the analysis the researchers noted The survey sample is also too small to know the exact impact the diseases had on Napoleon s army What changes with our inquiry is the fact that now we have direct evidence there were several different infectious diseases present in this site Rascovan reported It is likely that more diseases were at play that have yet to be detected he added Cecil Lewis an ancient DNA researcher who studies the human microbiome explained the results were not particularly surprising but he called it a meaningful contribution to our understanding of the demise of Napoleon s army Lewis vice president of academics at the Oklahoma School of Science and Mathematics was not involved with the investigation We are now in a period where ancient DNA studies can contribute more nuance to the understanding of such historic events which is exciting Lewis disclosed in an email Studying historical and ancient pathogens their place in history offers a glimpse into the evolutionary paths organisms have taken particular now extinct others forming the foundation of present-day pathogens These content help us better understand the possibilities for how pathogens can impact lives evolve and persist which is crucial for anticipating and managing future threats Paratyphoid fever and relapsing fever are still around currently but are not as common or as deadly Napoleon survived the retreat but his dwindling army ultimately contributed to his fall from power a meager years later Something that is quite impressive is how in so little time since with the first research to in current times the technologies have been developed so much that we can do things that were impossible to even conceive a limited years ago and now are accomplishable Rascovan mentioned So I am very excited to think what is going to be next in terms of technological developments