Long COVID or Lyme Disease? Why the Symptoms Overlap
Fatigue and brain fog are common.
Long COVID is often assumed.
But it’s not always the answer.
Many patients with fatigue, brain fog, dizziness, and post-viral symptoms are now labeled with Long COVID—but not all of them had COVID.
COVID-19 vs Lyme Disease: What’s the Difference?
COVID-19 and Lyme disease can cause similar long-term symptoms—including fatigue, brain fog, dizziness, and exercise intolerance—but they are different conditions with different causes and treatments.
Long COVID follows a viral infection, while Lyme disease is caused by a tick-borne bacterial infection.
If symptoms persist or don’t match a typical COVID pattern, Lyme disease and co-infections should be considered.
When It’s Not Long COVID—It’s Lyme
In the wake of the pandemic, we’ve become more aware of how a virus can lead to long-term, multisystem illness. That’s been a good thing.
Patients with brain fog, fatigue, and shortness of breath are no longer automatically dismissed. They’re told it might be Long COVID—and for many, that’s exactly what it is.
But not every post-viral–looking syndrome is post-viral. And not every case labeled Long COVID is the full story.
In my practice, I’ve seen patients whose symptoms—fatigue, headaches, lightheadedness, poor sleep, and word-finding issues—were immediately attributed to Long COVID.
Some had never tested positive. Others had recovered from COVID without issue—only to become chronically ill months or even years later.
In many of those cases, it wasn’t Long COVID.
It was Lyme disease—or a co-infection like Babesia or Bartonella.
And no one had looked.
When Labels Limit the Diagnosis
Long COVID has become a kind of medical shortcut.
It’s a real condition—but it can also become a convenient label when the work of a thorough differential diagnosis gets skipped.
When physicians assume symptoms must be from COVID, they may not ask about:
- Tick exposure
- Unexplained rashes
- Seasonal or geographic risk
- Prior flu-like illnesses that were never diagnosed
- Tick-borne co-infections
I’ve seen patients treated for months as though they had Long COVID—when the missing piece was an untreated tick-borne illness.
Lyme and Long COVID Can Share Similar Symptoms
The overlap between Lyme disease and Long COVID is significant.
Both conditions may involve immune, neurologic, and autonomic dysfunction. The challenge is determining whether a tick-borne illness has been overlooked in patients whose symptoms persist or evolve.
Both conditions can cause:
- Brain fog
- Chronic fatigue
- Autonomic dysfunction (POTS)
- Cognitive impairment
- Exercise intolerance
- Sleep disruption
- Mood changes
- Migratory pain
- Gastrointestinal symptoms
- Neurologic complaints
Patients with dizziness, lightheadedness, palpitations, or exercise intolerance may also develop symptoms related to autonomic dysfunction in Lyme disease.
So what’s the difference?
The treatment—and the risk of missing it.
While there are still limited treatment options for Long COVID, Lyme disease and associated co-infections can often be treated—if they are recognized.
The Cost of Delay
I’ve had patients who spent a year or more under the Long COVID umbrella before someone asked a different question:
“Could this be Lyme disease?”
By then, their symptoms had worsened.
Their trust had eroded.
Their hope had faded.
When the diagnosis finally shifted—and treatment began—improvement followed.
Not always quickly. Not always completely.
But often enough to matter.
We Owe Patients More Than Assumptions
The recognition of Long COVID has helped many patients.
But it should not end the diagnostic process—especially when the story doesn’t quite fit.
If symptoms persist, evolve, or fail to respond as expected, it’s worth asking:
- Was Lyme disease thoroughly evaluated?
- Were tick-borne co-infections considered?
- Or were they never part of the discussion?
Sometimes the answer isn’t a new virus.
It’s an older infection—still waiting to be treated.
Patients looking for broader symptom patterns can also review the Lyme disease symptoms guide.
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
Lyme is the #1 misdiagnosed disease, 3x the rate of syphilis, the only other spiral-shaped bacteria that can corkscrew its way into all tissues. Lyme is much worse as it is a persister, has no good early tests, no outward signs and no good late treatment. Medical denialism is a tragedy that has harmed children and families for decades, millions of times worse than the Tuskegee Scandal when syphilis went untreated. The best way to help patients would be to REQUIRE NIH and all gov’t and ducational institutions whose mission is public health to budget at least half to the most costly, disabling and misdiagnosed diseases. Lyme would be on all 3 lists.
Dr. Cameron, thank you for all of this valuable and helpful information. And thank you for all of your research and dedication to lyme and other tick-borne diseases. You have helped so many people, and I for one, am grateful to you. God bless.
“Thank you. I truly believe God led me here for a reason—and it’s been a blessing to serve this community. May He continue to guide and heal us all.”
Thank you Dr Cameron. Going thru a flare up. 2nd one in a month. Last 24 hours and extreme aches , migraine, sweating, low grade fever and then gone just like that. Haven’t had lymes in 15 years but it feels like it. Also, I had meningitis a year after Lymes and it feels like that too. Good times 😉 Praise God for people like you helping people like me 🙏
Thank you 🙏 I’m sorry you’re going through this flare-up. I’ve seen patients experience this even years after initial infection. You’re not alone—and I’m grateful you’re still pushing forward. Praise God indeed.