Mapping Lyme Disease Bacteria to Improve Patient Care

Genetic analysis of the Lyme disease bacterium may pave the way for improved diagnosis, treatment and prevention of the tick-borne disease.

By mapping the complete genetic makeup of 47 strains of the bacteria that cause Lyme disease from around the world, an international team has created a powerful resource for identifying the specific bacterial strains that infect patients. The researchers say this will allow for more precise diagnostic tests and treatments tailored to the exact type of bacteria causing each patient's disease.

“This comprehensive, high-quality sequence survey of Lyme disease and associated bacteria provides the foundation to move the field forward. A full range of contemporary research projects, from clinical to public health, ecology, evolution, bacterial physiology, medical tool development and host-bacterial interactions, will benefit from this work.”

Stephen Schutzer, study co-author and professor of medicine at Rutgers New Jersey Medical School, Rutgers University

The researchers said the genetic information discovered in the study explains how the bacteria evolves and spreads, that the genes are essential for survival and may help scientists develop a more effective vaccine against Lyme disease.

Lyme disease is the most common tick-borne disease in North America and Europe, affecting hundreds of thousands of people annually. Borrelia burgdorferi sensu largo This group is transmitted to humans through the bite of an infected tick. Symptoms include fever, headache, fatigue and a characteristic skin rash. If left untreated, the infection can spread to the joints, heart and nervous system, causing more serious complications.

Cases have been rising steadily — with 476,000 new cases in the United States each year — and climate change could accelerate the increase, the study authors said.

The research team sequenced the entire genome of the Lyme disease bacterium, analyzing all 23 known species in this group, most of which had not been sequenced prior to this study. The project, funded by the National Institutes of Health, included multiple strains of the bacteria most commonly associated with human infections, as well as species not previously known to cause disease in humans.

By comparing these genomes, the researchers were able to reconstruct the evolutionary history of the Lyme disease bacterium, pushing its origin back millions of years. They found that the bacterium likely emerged before the breakup of the ancient supercontinent Pangaea, which could explain its current global distribution.

The study also revealed how these bacteria exchange genetic material within and between species. This process, called recombination, allows bacteria to rapidly evolve and adapt to new environments. The researchers identified specific hotspots within the bacterial genomes where this gene exchange occurs most frequently, which often involve genes that help the bacteria interact with their tick vectors and animal hosts.

“Understanding how these bacteria evolve and exchange genetic material will enable us to better predict and respond to potential changes in bacterial behavior, particularly their ability to cause disease in humans,” said Weigang Qiu, a professor of biology at the City University of New York and lead author of the study.

To facilitate their ongoing research, the team developed a web-based software tool (BorreliaBase.org) that allows scientists to make comparisons. Borrelia We will analyze the genome to identify determinants of its ability to infect humans.

The researchers plan to further analyze Lyme disease strains, especially from less-studied regions, and to investigate the function of genes unique to disease-causing strains, with the hope of identifying new targets for therapeutic intervention.

As the geographic range of Lyme disease expands due to factors such as climate change, this study provides valuable tools and insights to combat a growing public health threat.

“This is a groundbreaking study and a body of work that will provide researchers with data and tools to better tailor treatment for all causes of Lyme disease and provide a framework for similar approaches to other infectious diseases caused by pathogens,” said Benjamin Luft, MD, Edmund D. Pellegrino Professor of Medicine at Stony Brook University's Renaissance School of Medicine.

The study's 20 authors include Claire Fraser and Emmanuel Mongodin of the University of Maryland School of Medicine and Sherwood Casjens of the University of Utah School of Medicine. The research was also supported by the Steve and Alexandra Cohen Foundation.