All 23 known species of the bacteria that cause Lyme disease have been genetically mapped, according to results published in mBio. Weigang Qiu, PhD, and colleagues noted that there are 23 separate species of B. burgdorferi within the sensu lato group that can infect humans. The researchers mapped the complete genomes of all members of the group, including those species known to cause the most disease in people. While the 23 species are found across the globe, genomic comparisons suggest the bacteria may have originated when the continents were massed together as the supercontinent Pangaea. Further, the research showed that the species are adept at sharing genetic material that allows them to adapt, which also helps them infect animals and people more effectively. “By understanding how these bacteria evolve and exchange genetic material, we’re better equipped to predict and respond to changes in their behavior, including potential shifts in their ability to cause disease in humans,” Dr. Qiu said.