In this landmark episode of the Tick Boot Camp Podcast, hosts Richard Johannessen and Matt Sabatello sit down with Dr. Alan MacDonald, a pioneering hospital pathologist whose work has shaped — and challenged — the understanding of Lyme disease for more than four decades.

Often referred to as “the Lyme doctor’s doctor,” Dr. MacDonald was among the earliest physicians investigating Lyme disease in the late 1970s and early 1980s, during the initial outbreak on Long Island, New York. While many of his findings were dismissed or attacked at the time, decades later they continue to resurface in modern research — increasingly validated by advances in molecular diagnostics.

This episode captures Dr. MacDonald’s scientific journey, his discoveries, and the systemic resistance he faced while uncovering uncomfortable truths about Lyme disease, chronic infection, and neurodegeneration.

About Dr. Alan MacDonald

Dr. Alan MacDonald was a retired hospital pathologist who trained at Tufts University and Columbia University College of Physicians and Surgeons, later serving as Chief Resident in Pathology at NYU Bellevue. He spent many years working at Southampton Hospital on Long Island, where he became deeply involved in early Lyme disease diagnostics and research.

As a pathologist, Dr. MacDonald specialized in diagnosis through tissue, blood, and microscopy, earning the nickname “doctor’s doctor.” His career focused on uncovering disease at the cellular and molecular level — especially where conventional testing fell short.

Update: Dr. MacDonald recently passed away, but his work continues to influence Lyme research, neurodegenerative disease studies, and the broader conversation around chronic infection.

Key Topics Covered in This Episode

The Early Days of Lyme Disease on Long Island

Dr. MacDonald recounts being on the front lines as Lyme disease first emerged near Shelter Island, just miles from Southampton Hospital. He describes collaborating with early Lyme pioneers, setting up one of the first hospital-based Lyme testing labs, and performing diagnostic work before standardized tests even existed.

Why Lyme Disease Is a Polymicrobial Infection

Contrary to the idea that Lyme disease is caused by a single bacterium, Dr. MacDonald explains why Lyme should be viewed as a polymicrobial illness. Ticks carry multiple pathogens, including Borrelia species, Babesia, Ehrlichia, Anaplasma, parasites, and more — often transmitted simultaneously.

Mother-to-Child Transmission of Lyme Disease

One of Dr. MacDonald’s most controversial early findings involved Borrelia burgdorferi detected in miscarried fetuses, placental tissue, and umbilical cord blood. He explains why transplacental transmission of Lyme disease is biologically unavoidable — and why this evidence was rejected despite clear pathology.

Lyme Disease and Alzheimer’s, Dementia, and MS

Decades before today’s research, Dr. MacDonald identified Borrelia spirochetes, DNA, and biofilms in Alzheimer’s disease brains. He draws parallels to syphilis, another spirochetal infection long known to cause dementia, and explains why infection-driven neurodegeneration has been so fiercely resisted in Alzheimer’s research.

He also discusses connections between Lyme disease and:

• Alzheimer’s disease

• Lewy Body Dementia

• Multiple Sclerosis–like syndromes

• Parkinson’s disease

Biofilms: The Missing Piece in Chronic Lyme

Dr. MacDonald explains how Borrelia forms biofilms — structured bacterial communities that protect the organism from antibiotics and immune attack. He describes finding biofilms:

• In Alzheimer’s plaques

• In skin manifestations of Lyme

• Circulating in blood

• Embedded in chronic tissue infections

He emphasizes that biofilms are always a marker of chronic infection, not acute disease.

Why Lyme Testing Fails So Many Patients

This episode provides a deep dive into why standard Lyme tests are unreliable. Dr. MacDonald explains:

• Why antibody tests miss chronic infection

• How Borrelia changes form (spirochete, cystic, L-form, granular)

• Why DNA-based testing is the future

• How immune complexes and biofilms create false negatives

He also discusses advanced diagnostic tools like FISH (fluorescence in situ hybridization) and DNA probes — many of which he developed or refined himself.

Blood Transfusions and Lyme Disease

Dr. MacDonald outlines the scientific basis for Lyme disease transmission via blood transfusion, referencing Babesia’s known transfusion risk and Borrelia’s ability to survive in stored blood. He raises concerns about undetected European Borrelia strains entering blood supplies.

Parasites, Lyme Disease, and Chronic Illness

One of the most eye-opening sections of the interview explores Dr. MacDonald’s discovery of parasitic organisms in spinal fluid and brain tissue, including microscopic tapeworm-like larvae. He explains:

• The symbiotic relationship between parasites and Borrelia

• How parasites may shelter Lyme bacteria

• Why antiparasitic treatment may be critical in chronic Lyme cases

Politics, Suppression, and the Standard of Care

Dr. MacDonald speaks candidly about:

• Being accused of fraud for publishing Lyme pathology findings

• The role of academic gatekeeping in suppressing research

• How medical politics shape “standard of care”

• Why doctors fear treating chronic Lyme patients

He explains how lack of publication access directly harms patients by preventing clinicians from practicing evidence-based, patient-centered medicine.

A Legacy That Continues

Throughout this episode, it becomes clear that many of Dr. MacDonald’s “controversial” ideas were simply ahead of their time. From congenital Lyme disease to biofilms, neurodegeneration, and DNA-based diagnostics, modern science is now revisiting questions he raised decades ago.

Update: Though Dr. Alan MacDonald is no longer with us, his work lives on — in the research, the patients he helped, and the growing body of science finally willing to look where he told us to look all along.