Earliest evidence of fish tapeworm found at Must Farm in Cambridgeshire
Investigations at the 3,000-year-old site in Cambridgeshire known as ‘Britain’s Pompeii’ have yielded some grim secrets about the health and diet of its prehistoric inhabitants.
Must Farm, the late Bronze Age settlement near what is now Peterborough, was a village of wooden houses built on stilts above the water. It was destroyed in a fire, but artefacts from the homes were preserved in mud below the waterline, including food, cloth and jewellery.
Archaeologists at the University of Cambridge have now used microscopy techniques to analyse waterlogged coprolites - pieces of human and animal faeces - that were also preserved in the mud.
They detected ancient parasite eggs in the faeces and surrounding sediment, revealing that the inhabitants were infected by intestinal worms caught from foraging for food in lakes and waterways around the homes.
The study’s lead author, Dr Piers Mitchell, of Cambridge’s Department of Archaeology, said: “We have found the earliest evidence for fish tapeworm, Echinostoma worm, and giant kidney worm in Britain. These parasites are spread by eating raw aquatic animals such as fish, amphibians and molluscs. Living over slow-moving water may have protected the inhabitants from some parasites, but put them at risk of others if they ate fish or frogs.”
Fish tapeworms can live coiled up in intestines and reach 10m in length, with heavy infection leading to anaemia. There has been something of a resurgence in them because of the popularity of sushi, smoked salmon and ceviche.
Giant kidney worms can reach up to a metre in length and gradually destroy the organ, leading to kidney failure.
Echinostoma worms are up to 1cm in length, and heavy infection can cause inflammation of the intestinal lining.
At other Bronze Age sites in Europe, the eggs of roundworm have been found. But human and animal waste was disposed into water around Must Farm, which is thought to have prevented direct faecal pollution of the fenlanders’ food.
But with thick reedbeds leaving the fenland water quite stagnant, waste would have accumulated in surrounding channels, creating a fertile breeding ground for parasites to infect wildlife which, if eaten raw or not properly cooked, would have spread to residents.
The study’s first author, Marissa Ledger, also from the Department of Archaeology, said: “The dumping of excrement into the freshwater channel in which the settlement was built, and consumption of aquatic organisms from the surrounding area, created an ideal nexus for infection with various species of intestinal parasite.
“As writing was only introduced to Britain centuries later with the Romans, these people were unable to record what happened to them during their lives. This research enables us for the first time to clearly understand the infectious diseases experienced by prehistoric people living in the fens.”
Working with the University of Bristol’s organic chemistry unit, the team learned that some of the coprolites were human, while others were from dogs.
“Both humans and dogs were infected by similar parasitic worms, which suggests the humans were sharing their food or leftovers with their dogs,” said Marissa.
Pig whipworm and Capillaria worm were also found on the site and probably originated from the butchery and consumption of the intestines of farmed or hunted animals. It is believed but probably did not cause humans any harm.
Bronze Age sites like Must Farm have fewer parasite species than Neolithic sites.
“Our study fits with the broader pattern of a shrinking of the parasite ecosystem through time,” said Dr Mitchell. “Changes in diet, sanitation and human-animal relationships over millennia have affected rates of parasitic infection.
“We now need to study other sites in prehistoric Britain where people lived different lifestyles, to help us understand how our ancestors’ way of life affected their risk of developing infectious diseases.”
Must Farm, which dates to 900-800 BC, was discovered in 1999. Major excavations were carried out by the Cambridge Archaeological Unit between 2015 and 2016, funded by Historic England and Forterra Building Products.