A new study indicates that the retreat of Napoleon’s troops from Russia in 1812 was not solely due to typhus, but also to paratyphoid fever and louse-borne relapsing fever. This conclusion is based on an analysis of ancient DNA extracted from the teeth of 13 soldiers discovered in mass graves in Vilnius, Lithuania.
The research, which is still undergoing peer review for publication in a scientific journal, has been shared on the bioRxiv platform by scientists from the Pasteur Institute in Paris. During the tragic retreat, Napoleon’s Grande Armée, which initially numbered around 600,000 men, was nearly halved by the combined effects of cold, hunger, and disease.
While contemporary doctors documented cases of typhus with symptoms including fever, headaches, and skin eruptions, microbiologist Rémi Barbieri and his colleagues found no traces of the bacterium responsible for that disease (*Rickettsia prowazekii*) in the soldiers’ remains.
Instead, the ancient DNA analysis confirmed the presence of *Salmonella enterica*, which causes paratyphoid fever, and the bacterium *Borrelia recurrentis*, which is transmitted by lice and causes relapsing fever. The researchers note that while not always fatal, “louse-borne relapsing fever could significantly weaken individuals already exhausted.”
The absence of typhus in these particular samples does not rule it out as a major cause of casualties elsewhere. The researchers state that “analysis of a greater number of samples will be required to fully understand the spectrum of epidemic diseases that affected the Napoleonic army during the Russian retreat.” They propose that “a reasonable scenario for the death of these soldiers would be a combination of exhaustion, cold, and multiple diseases, including paratyphoid fever and louse-borne relapsing fever.”