Lice played a crucial role in the disastrous failure of Napoleon Bonaparte during his invasion of Russia in 1812. A genetic study conducted on the bones of the ill-fated army has revealed this fact.
Napoleon marched into Russia during the summer of 1812, leading the largest army in Europe at the time, with around half a million soldiers, advancing towards Moscow.
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French Emperor Napoleon Bonaparte defeated the army of Tsar Alexander I and Emperor Franz I of Austria at Austerlitz on December 2, 1805 |
The invasion was Napoleon’s response to Tsar Alexander I’s refusal to join the Continental System—a framework aimed at boycotting British trade and bolstering the French economy at the expense of other nations.
Six months later, the once-mighty army dwindled to just 25,000 soldiers, retreating toward Vilnius, the capital of Lithuania (on the eastern shore of the Baltic Sea), in bitterly cold weather. Ultimately, only 3,000 men survived the war, harsh conditions, and illness to continue their retreat. The deceased were buried in mass graves. One such grave, containing approximately 2,000 to 3,000 bodies, was discovered in 2001 at a construction site in Vilnius.
By analyzing the remaining bones, scientists found genetic evidence confirming that infectious diseases caused by lice were a major reason for the French withdrawal from Russia. Didier Raoult from the Mediterranean University in Marseille and his colleagues published this finding in the latest issue of The Journal of Infectious Diseases.
“We believe that diseases arising from lice caused most of the deaths in Napoleon’s army,” Raoult stated.
Human lice transmit three types of parasites: Borrelia recurrentis, Bartonella quintana, and Rickettsia prowazekii—responsible for relapsing fever, trench fever, and Rickettsial typhus.
Raoult and his team analyzed 2 kg of soil from the massive grave along with bone fragments, clothing remnants, and isolated the remains of five lice. Three of these lice carried DNA from the relapsing fever parasite.
Subsequently, in their examination of the dental pulp from 72 teeth taken from the remains of 35 soldiers, they found DNA from Bartonella quintana in seven individuals.
“We are confident that this discovery provides solid evidence that the soldiers suffered from trench fever,” the research team wrote.
They also identified DNA from the parasite Rickettsia prowazekii in three other soldiers, demonstrating that Napoleon’s troops were also afflicted by Rickettsial typhus.
In total, nearly one-third of the French Emperor’s soldiers buried in Vilnius were infected with diseases carried by lice, the researchers concluded.
T. An (according to Discovery)