Nearly 2,000 years ago, Roman soldiers stationed on the edge of the empire faced more than cold winds, enemy raids, and homesickness.
New research shows that many of them were also battling painful intestinal parasites that likely weakened their health and made daily life far more miserable.
A recent study of ancient sewer drains at Vindolanda, a Roman fort just south of Hadrian’s Wall, has revealed that the fort’s occupants were infected with at least three types of gut parasites.
These included roundworm, whipworm, and a microscopic parasite called Giardia duodenalis, which causes severe diarrhea. This marks the first time Giardia has ever been identified in Roman Britain.
Vindolanda was a busy military base guarding the northern frontier of Roman Britain. Hadrian’s Wall, built in the early second century AD, stretched from the North Sea to the Irish Sea and was lined with forts, towers, and garrisons. Soldiers from across the Roman Empire—infantry, cavalry, and archers—were stationed there to defend against tribes from the north.
Vindolanda itself is famous for its exceptional preservation, including hundreds of ink-written wooden tablets and thousands of Roman leather shoes that give vivid insight into everyday life.
The parasite evidence comes from sediment taken from a sewer drain connected to a communal latrine and bath complex built in the third century AD.
The research was carried out by scientists from the University of Cambridge and the University of Oxford, and published in the journal Parasitology.
Researchers collected 50 sediment samples along the length of the nine-meter drain, which once carried human waste away from the latrine and into a nearby stream.
Mixed in with the sediment were everyday Roman objects such as pottery fragments, beads, and animal bones. Under microscopes, scientists searched for parasite eggs left behind in human waste.
More than a quarter of the samples contained eggs from roundworms or whipworms. In one particularly telling sample, scientists found evidence of both worm species and then used advanced biochemical testing to detect traces of Giardia.
The team also examined sediment from a defensive ditch belonging to an even earlier fort at Vindolanda, built in the late first century AD, and found roundworm and whipworm there as well.
These parasites spread when food, water, or hands become contaminated with human feces, a sign that sanitation was far from effective. Roundworms can grow up to 30 centimeters long inside the body, while whipworms embed themselves in the intestines. Giardia, though invisible to the naked eye, can cause explosive diarrhea, dehydration, extreme fatigue, and weight loss.
The health impact on soldiers would have been serious. Chronic infections could lead to malnutrition, stomach pain, and persistent diarrhea, reducing a soldier’s strength and fitness for duty. In summer months, outbreaks of Giardia caused by contaminated water could have left some soldiers dangerously dehydrated for weeks.
What’s striking is that Vindolanda did have communal latrines and a sewer system—features often associated with Roman engineering sophistication. Yet these measures were clearly not enough to stop disease from spreading. Researchers note that similar parasite patterns have been found at Roman military sites across Europe, including in Austria, the Netherlands, and Scotland.
Urban Roman centers such as London and York show a different parasite profile, including tapeworms linked to eating raw or undercooked fish and meat. This suggests that lifestyle, diet, and living conditions played a major role in shaping health risks across the empire.
For archaeologists, the study highlights how much ancient parasites can tell us about the realities of past lives. Rather than the image of disciplined, well-fed soldiers guarding a mighty wall, the evidence points to men coping with cold, hardship, and constant stomach illness.
As one famous poem imagines a Roman soldier complaining of lice and a runny nose while guarding a rain-soaked wall, modern science suggests something else can be added to the list of complaints: severe and ongoing gut trouble.
