Leprosy passed between medieval squirrels and humans, study suggests

Unearthing Medieval Connections: Leprosy Transmission Between Humans and Red Squirrels

Introduction

In a fascinating revelation, recent genetic analysis of historical samples from Winchester sheds light on the transmission of leprosy between humans and red squirrels in medieval England. The findings provide crucial insights into the potential role of the fur trade in the spread of this ancient infectious disease.

Historical Context

Leprosy, caused by Mycobacterium leprae, has plagued humanity for centuries, causing suffering and disfigurement. While predominantly found in south-east Asia today, medieval England was also afflicted by this disease, affecting individuals across all social strata.

Previous Research

Earlier studies hinted at a connection between leprosy strains in humans and red squirrels in medieval England, particularly those imported from Viking Scandinavia. However, concrete evidence was lacking until now.

The Study

Led by Dr. Sarah Inskip from the University of Leicester, an international team conducted genetic analysis on samples from Winchester, a pivotal medieval city with significant fur trade activity and a leper hospital. The team examined DNA from human remains dating back 900 to 600 years and a red squirrel bone found in a furrier pit dating back 1,000 to 900 years. Add More

Genetic Analysis

Analysis of the DNA revealed striking similarities in leprosy strains present in both humans and squirrels from medieval Winchester. Surprisingly, the strains found in archaeological samples were more closely related than those in modern squirrels, suggesting a historical transmission between the two species.

Implications

While the exact transmission direction remains uncertain, the findings underscore the potential for disease exchange between humans and animals. The fur trade emerges as a possible mechanism for transmission, with thousands of squirrel skins imported to England during the medieval period. Additionally, the widespread keeping of squirrels as pets offered another avenue for contact between humans and infected animals.

Future Directions

The study raises important questions about contemporary leprosy cases and their potential link to animal hosts. Investigating the presence of Mycobacterium leprae in communities where leprosy persists could offer valuable insights into disease transmission dynamics.

Conclusion

The discovery of similar leprosy strains in medieval humans and red squirrels provides compelling evidence of historical disease transmission between the two species. As we unravel the complex interplay between humans, animals, and infectious diseases, this research underscores the importance of interdisciplinary approaches in understanding and combating ancient and contemporary health challenges.Add More