Scientists Uncover Deadly Bacteria from Napoleon’s 1812 Retreat

A recent study has revealed traces of deadly bacteria that affected Napoleon Bonaparte’s army during its ill-fated retreat from Russia in 1812. This research, published in the journal Current Biology on November 3, 2023, provides new insights into the health conditions faced by French soldiers as they retreated through harsh winter conditions.

The study focused on DNA extracted from the teeth of French soldiers buried in a mass grave in Vilnius, Lithuania. These soldiers were part of Napoleon’s Grande Armée during the disastrous campaign, which saw approximately 300,000 soldiers perish. Researchers discovered bacteria responsible for paratyphoid fever and louse-borne relapsing fever within the remains, highlighting the presence of multiple infections among troops weakened by starvation and extreme cold.

Historically, the brutal conditions of the Russian winter have been well-documented, but the identification of these specific pathogens marks a significant advancement in understanding the factors contributing to the soldiers’ demise. According to study author Nicolás Rascovan, “Vilnius was a key waypoint on the 1812 retreat route.” The mass grave, containing the remains of up to 3,000 soldiers, serves as a poignant reminder of the human cost of this military campaign.

Rascovan noted that many soldiers arriving in Vilnius were “exhausted, starving and ill,” with a substantial number dying and being buried quickly in mass graves. While starvation and typhus have long been recognized as major causes of death, the study confirms that paratyphoid fever and louse-borne relapsing fever also played a role in the high mortality rates. “These may have contributed to debilitation and mortality,” he added.

In their analysis, the researchers found that four of the thirteen soldiers tested positive for the paratyphoid fever bacterium, while two others were positive for the relapsing fever bacterium. Both infections are known to cause symptoms such as fever, headache, and weakness, and can spread rapidly in crowded and unsanitary conditions. Paratyphoid fever typically spreads through contaminated food and water, whereas louse-borne relapsing fever is transmitted by body lice.

Rascovan emphasized the importance of studying ancient DNA, stating that it allows researchers to identify infections that historical accounts may overlook. He pointed out that “the co-occurrence of pathogens with different transmission routes underscores how dire sanitary conditions were.” This research opens the door for future studies at additional sites to further refine our understanding of the disease landscape during Napoleon’s retreat in 1812.

The findings not only shed light on the health challenges faced by soldiers but also serve as a reminder of the historical implications of warfare, particularly in harsh environments. As researchers continue to explore this area, they aim to enhance our knowledge of historical epidemics and their impacts on military campaigns.