Dr Inskip said: “That [leprosy] may also come from squirrels is an interesting idea.”
King’s Lynn and Yarmouth in Norfolk were “significant ports for fur imports” from Denmark and Sweden at this time, she added.
The animals were also sometimes kept as pets.
The leprosy strain has previously been found in the skeleton of a man from Great Chesterford near Cambridge, dating from 415 to 545 AD, suggesting it had persisted for hundreds of years in south east England.
Dr Inskip said: “This new evidence, coupled with the prevalence of leper hospitals in East Anglia from the 11th Century onwards, adds weight to the idea the disease was endemic in this region earlier than other parts of the country.”