Lyme disease is the most common vector-borne illness in the US, transmitted to humans by the bite of infected ticks.
Though the bites are tiny, the disease can affect a person for life, and the way we treat it speaks to some of the biggest problems with our healthcare system, like inequality in the distribution of diagnosis, and the speed at which misinformation can destroy public trust in the scientific method.
Caused by the bacterium borrelia burgdorferi, early Lyme disease symptoms typically include:
- Muscle and joint aches
- Fever and chills
- Fatigue and ‘brain fog’
- Swollen lymph nodes
- A Lyme disease rash (often described as a “bullseye”)
That last one, however, no matter how synonymous Lyme disease has become with the bullseye-shaped rash, only actually appears in about 20% of patients! As Dr. John Aucott, Director of the Johns Hopkins Lyme Disease Clinical Research Center, told us on our podcast ‘Your Brain On… Lyme Disease’:
People love to put the pictures of the classic target lesion, the bullseye, like the sign of a Target department store! That’s only about 20% of the lesions. Actually, the majority are uniformly red, and this leads to a lot of misdiagnosis.
We also spoke to Dr. Richard Marconi, Professor of Microbiology and Immunology at Virginia Commonwealth University, about the future of Lyme disease vaccines. We’ll get to those shortly.
Neurological impacts of Lyme disease
If Lyme disease is caught early, a short course of antibiotics is often curative. But if left untreated, or if treatment fails to fully resolve symptoms, the bacteria can spread throughout the body and trigger a wide range of neurological and systemic symptoms, including:
- Brain fog
- Fatigue
- Shooting pains or numbness
- Facial palsy (e.g. Bell’s palsy)
- Cognitive difficulties
- Depression and anxiety
What is Post-Treatment Lyme Disease Syndrome (PTLDS)?
One of the most misunderstood phrases in medicine today is “chronic Lyme disease.” In the annals of clinical research, it has a more specific and studied name: Post-Treatment Lyme Disease Syndrome, or PTLDS.
It’s defined as a group of persistent symptoms that remain six months or more after standard antibiotic treatment for Lyme disease.
“We call it post-treatment Lyme disease,” Dr. Aucott told us. “Very similar in many ways to long COVID or chronic fatigue syndrome. It’s an illness that’s triggered by infection, but the infection may [already] be gone.”
Common PTLDS symptoms include:
- Long-lasting fatigue
- Joint or muscle pain
- Trouble concentrating (“brain fog”)
- Sleep disturbances
- Mood changes
In functional MRI and PET scans, Dr. Aucott’s team has even found signs of glial cell inflammation, suggesting neuroimmune disruption in patients with PTLDS — a biological signature of the illness.
Why is Lyme disease so hard to diagnose?
The symptomology of Lyme disease isn’t as straightforward as many others:
- The classic rash is often absent
- Antibody-based blood tests have limitations: they can be falsely negative early on and can remain positive for years after infection, making it hard to tell if someone currently has Lyme
- Symptoms overlap with other conditions: fibromyalgia, chronic fatigue syndrome, MS, and even depression
- Testing technology lags behind the complexity of the disease
This diagnostic ambiguity has been a breeding ground for misinformation and exploitation.
Lyme disease misinformation, and the vulnerability of patients
As scientists, we empathize with patients who feel abandoned by a system that doesn’t validate their pain. And we also see the cost of that vacuum: one filled by pseudoscience, overpriced treatments, and unproven diagnostics.
Dr. Aucott agreed:
“I am very sympathetic to the individuals… they’re often told there’s nothing wrong with them, that it’s all in their head. That’s not true.”
Unfortunately, desperation can make patients vulnerable. In some ‘chronic Lyme’ clinics, patients are offered unvalidated lab tests, long-term antibiotics, IV therapies, or herbal concoctions at great financial (and sometimes physical) cost. These charlatans thrive on people’s hope, in the gap between suffering and uncertainty.”
Why are Lyme disease cases rising and spreading?
Dr. Aucott told us:
“We’ve recreated the perfect ecology to promote the proliferation of Lyme disease.”
Here’s how:
- Warmer winters and climate change
- Suburban sprawl into previously wooded areas
- Expanding deer and tick populations
- Lack of public awareness and preventive strategies
What happened to the LYMErix vaccine?
Many people are surprised to learn that there was once a human Lyme disease vaccine. It worked! And then it disappeared.
Dr. Richard Marconi explained:
“There’s a lot of misunderstanding about LYMErix and why it was pulled from the market.
“LYMErix entered the market in 1998, but shortly after, there were some anecdotal reports that it might be causing some significant adverse rheumatological events — arthritis, etc.
“A full analysis showed that was not the case. There was really no evidence to support that. It was essentially withdrawn from the market by its manufacturer, really due to declining sales.
“And not only declining sales, but also class action lawsuits that were being filed, contesting that the vaccine was responsible for some serious adverse events.”
That original vaccine, LYMErix, was 76% effective, but public concerns about side effects (later disproven) and a lack of commercial viability led to its withdrawal in 2002.
Is a new Lyme disease vaccine on the way?
Yes, several! Dr. Marconi is leading one of the most promising efforts.
His team at Virginia Commonwealth University are working on a next-generation Lyme vaccine that:
- Targets bacteria in both the tick and the human body
- Contains multiple protein variants to match different strains
- Could potentially protect against other tick-borne illnesses in a single shot
Dr. Marconi broke it down:
“We’ve modified the vaccine formulation to adapt it for humans. It contains two proteins — one is an OspC chimeric epitope protein, and the other is based on epitopes from a couple of different proteins.
“Where we think it holds an advantage is that this type of vaccine can elicit antibodies that can kill the bacteria both in the tick as well as in the mammal.
“And because of its design, it’s able to elicit memory immune responses that can provide for longer-term protection.
“We’re optimistic. People want protection. Everybody knows about Lyme disease — and most people know someone who’s had it.”
Prevention and precaution against Lyme disease
Until a vaccine becomes widely available, prevention is still your best defense:
- Avoid high-risk wooded and brushy areas
- Use DEET or permethrin insect repellents
- Wear long sleeves and tuck pants into socks
- Check your body (and scalp) after outdoor activities
- Shower within two hours of being outdoors
- Remove ticks carefully using a fine-tipped tweezer
- Save the tick in a sealed container if possible, for identification
- Seek medical care promptly if you notice a rash or flu-like symptoms
Lyme disease isn’t just a disease of the nervous system. It’s a disease of trust.
Whenever somebody has an answer to everything, they’re not to be trusted. The nature of science is that there are things we don’t know. But we keep asking. That’s how we build trust.
The path forward isn’t just better tests or vaccines. It’s better conversations. Between researchers and patients. Between doctors and communities. Between science and the public.
About The Author
Dean Sherzai, MD, PhD
Dr. Dean Sherzai is co-director of the Alzheimer’s Prevention Program at Loma Linda University. Dean trained in Neurology at Georgetown University School of Medicine, and completed fellowships in neurodegenerative diseases and dementia at the National Institutes of Health and UC San Diego. He also holds a PhD in Healthcare Leadership with a focus on community health from Andrews University.
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