For centuries, rats and fleas have been fingered as the culprits responsible for the Black Death, the medieval plague that killed as many as two thirds of Europe’s population.

But historians studying 14th-century court records from Dorset believe they may have uncovered evidence that exonerates them. The parchment records, contained in a recently-discovered archive, reveal that an estimated 50 per cent of the 2,000 people living in Gillingham died within four months of the Black Death reaching the town in October 1348.

The deaths are recorded in land transfers lodged with the manorial court which – unusually for the period – sat every three weeks, giving a clear picture of who had died and when. The records show that 190 of the 300 tenants holding land in the town died during the winter of 1348-49, at a time when a form of bubonic plague spread by rat fleas would have been dormant.

Experts now believe that the Black Death is more likely to have been a viral infection, similar to haemorrhagic fever or ebola, that spread from person to person.