Lyme disease misdiagnosed as Long COVID

After 37 years treating Lyme disease, I’ve seen an increasing number of patients diagnosed with Long COVID when infection was the underlying cause. A woman was told her fatigue, brain fog, dizziness, and poor sleep were just viral aftereffects. Some reassured her it would fade. Others told her it was untreatable. But she wasn’t getting better. When I took a closer look, it wasn’t Long COVID. She was suffering from Lyme disease—misdiagnosed as Long COVID.

Similar Symptoms, Different Causes

It’s easy to see why the confusion happened. Both Lyme disease and Long COVID can cause:

• Brain fog
• Chronic fatigue
• POTS or lightheadedness
• Mood changes
• Migratory pain
• Exercise intolerance
• Poor sleep

But while Long COVID care remains mostly supportive, Lyme disease and its co-infections can be treated.

I’ve had patients who never had COVID—or recovered fully—then fell ill months later. The trigger? Not a virus, but an undiagnosed tick-borne illness.

The Risks of Mislabeling

Long COVID has helped validate persistent symptoms. But it’s also become a convenient catch-all.

When physicians assume all fatigue and brain fog are viral in origin, they often stop asking the right questions:

• Was Lyme disease truly ruled out?
• Were co-infections like Bartonella or Babesia ever considered?
• Were tests interpreted clinically—or dismissed if negative?

I’ve had patients go over a year under the Long COVID umbrella—without any improvement—until we found and treated the infection beneath it all.

How I Approach These Patients

Here’s how I approach these patients differently:

• Take a full history of outdoor exposure, travel, and past undiagnosed illnesses
• Review Lyme testing thoroughly—and go beyond standard two-tier tests
• Screen for tick-borne co-infections
• Start treatment based on symptoms and clinical suspicion—not just labs
• Reevaluate patients diagnosed with Long COVID if they’re not improving

Once we treat the infection, many so-called “post-COVID” symptoms start to fade.

For a comprehensive overview of the Long COVID and Lyme disease connection—including my peer-reviewed research on 889 patients—see Long COVID and Lyme Disease: What Patients Need to Know.

Frequently Asked Questions

Can Lyme disease be mistaken for Long COVID?
Yes. Both conditions cause brain fog, fatigue, POTS, and exercise intolerance, making them easy to confuse without proper testing.

What’s the difference between Long COVID and Lyme disease?
Long COVID follows confirmed SARS-CoV-2 infection. Lyme disease is a tick-borne bacterial infection that can be treated with antibiotics.

Should Long COVID patients be tested for Lyme disease?
Yes, particularly if symptoms began without confirmed COVID infection, or if Long COVID treatments aren’t helping after months of care.

Related Reading

Lyme Disease Misdiagnosis: Why It Happens and What Patients Need to Know
Long COVID and Lyme Disease: What Patients Need to Know
Similarities of Long COVID and Lyme Disease in Children
Case Study: Lyme Disease in a Patient with Long COVID
Is It Long COVID or Lyme Disease?