On Aug. 14, 2024, an international team of scientists announced they had sequenced the complete genomes of the Lyme disease bacteria – Borrelia. The research team sequenced the complete genomes of Lyme disease bacteria representing all 23 known species in the group. Most of these hadn’t been sequenced before this monumental effort.

The study also revealed how these bacteria exchange genetic material within and between species. This process, known as recombination, allows the bacteria to evolve rapidly and adapt to new environments. By comparing these genomes, the researchers reconstructed the evolutionary history of Lyme disease bacteria, tracing the origins back millions of years. They discovered the bacteria likely originated before the breakup of the ancient supercontinent Pangea, explaining the worldwide distribution. In the United States Lyme disease numbers are approaching 500,000 per year.