Is Lyme Disease Spreading in Europe? Climate Change, Diagnosis, and Risk
Lyme disease where it wasn’t expected?
Cases appearing outside known regions?
The spread of Lyme disease may be changing.
Is Lyme disease increasing in Europe? Research suggests that Lyme disease may be expanding into new regions, including areas where it has historically been considered rare or controversial.
A key pattern is geographic spread. Changing climate conditions, diagnostic gaps, and surveillance limitations may be contributing to the growing recognition of Lyme disease across Europe.
Start here: How Lyme disease spreads
Evidence of Lyme Disease in New Regions
A key pattern is emerging recognition. Lyme disease may be present in areas where it has not been widely documented.
In a study from Greece, researchers identified patients with antibodies to Borrelia burgdorferi and Borrelia afzelii—including individuals who had never traveled abroad.
These findings suggest possible local (autochthonous) transmission of Lyme disease.
However, the presence of Lyme disease in Greece remains debated, highlighting the challenges of confirming cases in regions with limited prior data.
Why Lyme Disease May Be Underrecognized
A key pattern is diagnostic gap. Lyme disease is difficult to detect and track.
Researchers reviewing Lyme disease trends in Europe identified several barriers:
- Variable surveillance systems across countries
- Differences in case definitions
- Limited sensitivity of diagnostic tests in early infection
- Difficulty distinguishing past from current infection
- Lack of reliable tools to monitor treatment response
These challenges can lead to underreporting and delayed diagnosis.
See limitations of Lyme disease testing.
The Role of Climate Change
A key pattern is environmental expansion. Climate change may be altering tick habitats.
Warmer temperatures and changing ecosystems allow ticks to survive in new regions, increasing the potential for Lyme disease transmission.
This may contribute to the growing number of cases observed in both Europe and North America.
Different Borrelia Species in Europe
A key pattern is species variation. Lyme disease in Europe involves different bacterial strains.
While Borrelia burgdorferi is most common in the United States, European cases often involve:
- Borrelia afzelii
- Borrelia garinii
These species may present with different symptom patterns, including neurologic involvement.
Why Diagnosis Remains Challenging
A key pattern is clinical uncertainty. Symptoms vary widely and may mimic other conditions.
- Neurologic symptoms without clear cause
- Fatigue and cognitive changes
- Atypical or absent rash
These factors make Lyme disease difficult to recognize—especially in regions where clinicians are less familiar with it.
See Lyme disease misdiagnosis.
What This Means for Patients and Clinicians
A key pattern is increasing awareness. Recognition of Lyme disease may be improving—but challenges remain.
- Cases may occur outside traditionally recognized regions
- Travel history may be important
- Symptoms may not follow classic patterns
Improving surveillance, testing, and clinical awareness will be critical as Lyme disease continues to evolve.
Clinical Takeaway
Lyme disease appears to be spreading across Europe, influenced by environmental changes and diagnostic challenges.
Because symptoms and testing are variable, cases may be underrecognized—particularly in emerging regions.
If symptoms are unexplained or occur after travel, Lyme disease should be considered.
Start with the symptoms guide to better understand how Lyme disease may present.
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
