Lyme Disease in the South: Additional Evidence from North Carolina Ticks

Lyme disease is often thought of as a Northeastern illness. But growing evidence suggests that Borrelia burgdorferi-infected ticks may also be established in parts of the Southeast.

Findings from North Carolina raise an important point: infected ticks may persist in regions not always recognized as endemic.

Questing black-legged ticks (Ixodes scapularis) were collected from multiple sites on the Outer Banks of North Carolina between 1991 and 2009. Investigators detected Borrelia burgdorferi-infected ticks in 50% of the locations studied. :contentReference[oaicite:0]{index=0}

Consistent Detection Over Time

“The spirochetes were consistently detected in questing adult ticks over an 18-year period,” reports Levine from North Carolina State University. :contentReference[oaicite:1]{index=1}

Genetic sequencing confirmed that the isolates showed 98–99% homology with Borrelia burgdorferi sensu stricto, the same strain commonly associated with Lyme disease in the Northeast. :contentReference[oaicite:2]{index=2}

Multiple Hosts and Strains Identified

The organism was identified not only in ticks but also in animal reservoirs, including rice rats, white-footed mice, and marsh rabbits.

Investigators also identified multiple strains, including B31, JD1, and M11p, using advanced sequencing methods. Some strains have been associated with greater dissemination potential in early Lyme disease.

In addition, both northern/Midwestern and southern tick haplotypes were identified, suggesting a more complex transmission pattern than previously recognized.

Environmental and Regional Implications

Outdoor environments in the region—including walking paths and recreational areas—may present opportunities for human exposure.

Birds and other animals may also contribute to the spread of infected ticks across the Southeast, further complicating surveillance efforts.

Clinical Perspective

These findings reinforce the possibility that Lyme disease risk extends beyond traditionally recognized endemic areas, particularly in parts of the southeastern United States.

This highlights the importance of considering exposure risk based on environment and travel history, rather than relying solely on geographic classification.

Patients may benefit from awareness of tick bite prevention, recognition of Lyme disease symptoms, and understanding testing limitations.

References

1. Levine JF et al. Stable transmission of Borrelia burgdorferi on the Outer Banks of North Carolina. Zoonoses Public Health. 2016.
2. Additional references as cited.

Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.

Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention