During World War I, around 500,000 soldiers suffered from trench fever, an infection transmitted by clothes lice. But as DNA studies now show, this disease and its pathogen were already rampant almost 2000 years ago. Over the centuries soldiers and civilians became infected again and again, in some cases the degree of infection was 20 percent.
The first case of trench fever was reported by a British military doctor in the summer of 1915 from the Western Front during World War I. He treated a soldier who suffered from a recurring fever with dizziness, headaches and aching limbs. A little later there were other cases, until an estimated 500,000 soldiers fell ill with this “trench fever” in the course of the war.
Fever and chronic fatigue
This fever was usually not fatal for the sick, but it weakened them considerably – and that under the already harsh conditions of the trench warfare. “The typical cycle of this fever was repeated at five-day intervals, which is why it was also called five-day fever,” report Gérard Aboudharam from the University Hospital of Marseille and his team. “This resulted in a long-lasting illness, many soldiers were unfit for duty for at least two months and suffered from chronic exhaustion.” The courses ranged from almost asymptomatic cases to severe, life-threatening infections.
Today we know that trench fever is caused by the bacterium Bartonella quintana. This uses clothing lice as a carrier and enters the body with the excrement of these parasites via tiny cracks in the skin or scratched areas. “During wartime, the soldiers were often huddled together in cramped and unsanitary conditions for a long time,” the researchers explain. This promoted transmission by the lice. “In addition, despite the knowledge about the role of lice for soldiers, there were hardly any effective methods of disinfecting themselves.” It is therefore no wonder that trench fever was particularly rampant in the two world wars.
Not a disease of modern times or just of war
So far, however, it was unclear how widespread this fever and its pathogen Bartonella quintana was before these wars. Studies suggest that this bacterium has been present in humans for around 4000 years. In addition, it was detected by DNA analyzes in soldiers of Napoleon buried in front of Wilna in 1812 and in soldiers who died in Kassel in 1813/14. However, these were only isolated finds. In order to gain more clarity, Aboudharam and his team have now re-evaluated all known historical cases of trench fever and also carried out their own DNA analyzes on 145 deaths from the last 2000 years and from five European countries.
The result confirmed that trench fever was already widespread in Europe in ancient times – both among soldiers and civilians. For example, three out of five civilians buried in the French Besancon in the first century were positive; in the catacombs of St. Lucia and San Basilio in Italy, one in 28 and one in six deaths, respectively, were positive for Bartonella quintana. During the Napoleonic wars, four out of nine soldiers were infected; eight out of 28 dead were found to be positive for those investigated from the Crimean War from 1853 to 1856.
“The wide geographic and temporal distribution of these cases suggests that this infection was common in historical populations in Europe,” said Aboudharam and his team. Contrary to popular belief, soldiers were hardly affected more often than civilians – the infection rate hardly differed at 20 and almost 18 percent. Presumably this was due to the fact that at that time the hygienic conditions were unsatisfactory even among the normal population and that clothes lice were commonplace in many families and households.
Source: University of South Florida; Technical article: PLOS ONE, doi: 10.1371 / journal.pone.0239526