Lyme Disease Biofilm: Round Bodies, Blebs, and Persistence
Clusters of bacteria protecting themselves?
Reduced response to treatment?
Biofilms are one possible explanation under study.
Lyme disease biofilm formation may help explain how Borrelia burgdorferi persists in the body despite treatment.
Quick Answer: Borrelia burgdorferi can shift into different forms—including round bodies, blebs, and biofilms—which may influence how the infection behaves and responds to treatment.
Clinical Insight: These morphologic changes are one possible explanation for persistent symptoms, though their exact role in human disease remains under investigation.
Researchers have increasingly focused on these pleomorphic forms to better understand the biology of persistent Lyme disease.
This raises an important question: can changes in bacterial form contribute to treatment challenges in Lyme disease?
These patterns are part of broader mechanisms of chronic illness after Lyme disease.
Pleomorphic Forms of Borrelia burgdorferi
In an effort to better understand Lyme disease biofilm and other morphologic forms, Corak and colleagues grew B. burgdorferi cultures containing spirochetes, round bodies, blebs, and biofilm-dominated colonies.
They analyzed these forms using RNA sequencing and found that non-spirochete morphotypes could be induced by modifying growth conditions.
The authors described three major pleomorphic forms:
- Round bodies — spherical cells with intact, flexible membranes and internal flagella
- Bleb morphotype — characterized by outer membrane vesicles forming on the bacterial surface
- Lyme disease biofilm — multicellular communities embedded in a self-produced matrix
These forms differ not only in structure—but also in gene expression.
Round bodies showed expression patterns similar to spirochetes, while bleb and biofilm forms demonstrated distinct profiles.
Why Lyme Disease Biofilm May Matter
Researchers suggest that Lyme disease biofilm and bleb morphotypes may play a role in how B. burgdorferi survives and spreads within the host.
“Taken together, we believe that many of the ongoing controversies related to Lyme disease pathogenesis and treatment strategies could be resolved by improving our understanding of B. burgdorferi biology and evolution.”
These findings offer one possible explanation for why some patients experience persistent symptoms despite treatment.
However, the extent to which these forms contribute to ongoing infection in humans remains an area of active research.
Some of these patterns overlap with Lyme persister cells, which may also demonstrate tolerance to antibiotics in laboratory studies.
Biofilm, Persistence, and Treatment Challenges
Biofilms are structured communities of bacteria that may provide protection from environmental stress.
In laboratory models, biofilm-associated bacteria can behave differently from free-floating (planktonic) forms.
This has led to the hypothesis that biofilms and other morphologic variants could influence treatment response.
At the same time, translating laboratory findings into clinical practice remains complex.
Not all mechanisms observed in vitro have been confirmed in human disease.
Clinical Perspective
Understanding pleomorphic forms of B. burgdorferi may help explain variability in symptom patterns and treatment response.
However, no single mechanism fully explains persistent Lyme disease.
Patients with ongoing symptoms may benefit from review of Lyme disease symptoms, consideration of persistent Lyme disease mechanisms, and evaluation of potential coinfections.
Multiple factors—including immune response, inflammation, and coexisting conditions—likely contribute.
If symptoms continue after treatment, see persistent Lyme symptoms after treatment.
If symptoms improve and later return, see can Lyme disease come back years later.
Symptoms may also fluctuate over time. Learn more about why Lyme symptoms come and go.
The Bottom Line
Lyme disease biofilm and pleomorphic forms represent an important area of research.
These bacterial adaptations may help explain persistence—but their exact clinical significance is still being defined.
Ongoing research is needed to better understand how these mechanisms affect diagnosis and treatment.
Related Research on Persistent Lyme Disease
Scientists continue to explore whether biofilms, persister cells, and dormancy mechanisms contribute to persistent infection.
Related Articles:
Persister cells still a problem for Lyme disease patients
References:
- Corak et al. Pleomorphic Variants of Borreliella (syn. Borrelia) burgdorferi Express Evolutionary Distinct Transcriptomes. Int J Mol Sci. 2023.
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
I was the first to describe Round body form borrelia( cystic form)
in 1988. I am delighted to read your update from researchers in Croatia and Germany who describe on detail the molecular basis of cystic borrelia, and blebs of borrelia and biofilm borrelia communities.
Each “ variant” non spiral form of borrelia carry a molecular signature which differs from the “spiral “ form Gene expressions. These molecular signatures influence the synthesis of key “ variant” proteins
and provide an explanation for the failure of current serology test kits to detect these “ variant “ proteins.
Alan B MacDonald MD
I cannot believe it has been that many years ago. I started seeing Lyme disease patients in 1987.