Research reveals Roman soldiers plagued by parasites

By Stephen Beech

Roman soldiers defending Hadrian’s Wall were infected by parasites that cause serious stomach upsets, reveals new research.

An analysis of sewer drains from the Roman fort of Vindolanda, close to the iconic northern England landmark, has shown that the occupants were contaminated with three types of intestinal bug: roundworm, whipworm, and Giardia duodenalis.

The parasites are all spread by ineffective sanitation - with contamination of food, drink or hands by human faeces, say scientists.

Roundworms are 20cms to 30cms (7.8 to 11.8 inches) long while whipworms are about 5cms (2ins) long.

Giardia are microscopic protozoan parasites that cause outbreaks of diarrhea.

The findings, published in the journal Parasitology, are the first evidence for Giardia duodenalis in Roman Britain.

Hadrian’s Wall was built by the Romans in the early 2nd Century AD to defend their province of ‘Britannia’ from attack by tribes from the north, and remained in use until the end of the 4th Century.

It was defended by infantry, archery and cavalry units from across the Roman Empire.

The site of Vindolanda is located between Carlisle and Corbridge in Northumberland.

Vindolanda is known for organic objects preserved in the waterlogged soil at the site, including more than 1,000 thin wooden tablets written with ink that document daily life at the fort and a collection of over 5,000 Roman leather shoes.

The analysis of sediment from the sewer drain leading from the latrine block at the 3rd Century bath complex was performed jointly by researchers from the universities of Cambridge and Oxford.

A total of 50 sediment samples were taken along the length of the latrine drain, which measured around nine meters (29.5 ft) and carried waste from the communal latrine down to a stream north of the site.

Artefacts recovered from the drain include Roman beads, pottery and animal bones.

The samples were split between labs at Cambridge and Oxford, where researchers conducted microscope analysis to hunt for the ancient remains of helminth eggs: parasitic worm species that infect humans and other animals.

More than one in four of the samples (28%) contained either roundworm or whipworm eggs.

One sample contained remnants of both species, so the research team analyzed it using a bio-molecular technique called 'ELISA' - in which antibodies bind onto proteins produced by single-celled organisms, and found traces of Giardia duodenalis.

The researchers also took a sample connected to an earlier 1st Century fort, constructed around 85AD and abandoned by 91or 92 AD.

The sample came from a ditch that was part of the fort’s defensive system, and contained both roundworm and whipworm.

Dr. Marissa Ledger, who led the Cambridge component of the study, said: “The three types of parasites we found could have led to malnutrition and cause diarrhea in some of the Roman soldiers.

“While the Romans were aware of intestinal worms, there was little their doctors could do to clear infection by these parasites or help those experiencing diarrhea, meaning symptoms could persist and worsen.

"These chronic infections likely weakened soldiers, reducing fitness for duty.

"Helminths alone can cause nausea, cramping and diarrhea.”

Study senior author Dr. Piers Mitchell, from the University of Cambridge, said: “Some soldiers could have become severely ill from dehydration during summer outbreaks of Giardia, which are often linked to contaminated water and can infection dozens of people at a time.

"Untreated giardiasis can drag on for weeks, causing dramatic fatigue and weight loss.

“The presence of the fecal-oral parasites we found suggests conditions were ripe for other intestinal pathogens such as Salmonella and Shigella, which could have triggered additional disease outbreaks."

The researchers say the predominance of fecal-oral parasites at Vindolanda is similar to Roman military sites elsewhere, such as Carnuntum in Austria, Valkenburg on Rhine in the Netherlands, and Bearsden in Scotland.

Urban Roman sites - such as London and York - had a more diverse parasite range, including fish and meat tapeworms.

Dr. Patrik Flammer, who analyzed samples from Vindolanda at the University of Oxford, said: “Despite the fact that Vindolanda had communal latrines and a sewer system, this still did not protect the soldiers from infecting each other with these parasites."

Adrian Smith, who led the lab at Oxford, added: “The study of ancient parasites helps us to know the pathogens that infected our ancestors, how they varied with lifestyle, and how they changed over time.”

Dr. Andrew Birley, CEO of the Vindolanda Charitable Trust, welcomed the findings.

He said: “Excavations at Vindolanda continue to find new evidence that helps us to understand the incredible hardships faced by those posted to this north western frontier of the Roman Empire nearly 2,000 years ago, challenging our preconceptions about what life was really like in a Roman frontier fort and town.”