Tick-Borne Diseases Beyond Lyme: What Doctors May Miss
SYMPTOMS AFTER A TICK BITE—BUT TESTS ARE NEGATIVE?
IT MAY NOT BE LYME DISEASE ALONE
Some patients are told their symptoms don’t fit Lyme disease—or that nothing more can be done.
What if your symptoms don’t match Lyme disease—or your test is negative?
Quick Answer: Ticks can transmit multiple infections beyond Lyme disease. These include Borrelia miyamotoi, Rocky Mountain spotted fever, Bourbon virus, Heartland virus, Borrelia mayonii, and STARI—many of which are difficult to detect with standard testing.
Clinical Insight: When symptoms persist after tick exposure but Lyme tests are negative, clinicians should consider alternative tick-borne infections.
Tick-borne infections extend far beyond Lyme disease and common coinfections. A growing list of emerging pathogens adds complexity to diagnosis and treatment.
These infections are often missed. Symptoms overlap, testing is limited, and diagnosis may be delayed—similar to patterns seen in delayed Lyme diagnosis.
This overlap is also seen in Lyme disease symptoms, where presentations may not follow a predictable pattern.
Borrelia miyamotoi
Borrelia miyamotoi is a relapsing fever spirochete transmitted by the same ticks that carry Lyme disease.
Symptoms may include fever, chills, fatigue, headache, and muscle aches. Unlike Lyme disease, a rash is uncommon.
Standard Lyme disease tests do not reliably detect Borrelia miyamotoi, which may contribute to missed diagnoses.
Rocky Mountain Spotted Fever
Rocky Mountain spotted fever (RMSF) is a serious bacterial infection caused by Rickettsia rickettsii.
Symptoms may include fever, headache, rash, and muscle pain. Early treatment is critical, as delayed diagnosis can lead to severe complications.
Bourbon Virus
Bourbon virus is a rare but emerging tick-borne infection identified in the United States.
Symptoms include fever, fatigue, rash, and low blood cell counts. Limited testing availability makes diagnosis challenging.
Heartland Virus
Heartland virus is another emerging infection transmitted by ticks.
Patients may present with fever, fatigue, diarrhea, and low white blood cell counts. Like Bourbon virus, testing is limited and diagnosis may be delayed.
Borrelia mayonii
Borrelia mayonii is a recently identified species related to Lyme disease.
It may cause fever, nausea, rash, and neurologic symptoms. Some patients have higher levels of bacteria in the blood compared to typical Lyme disease.
Southern Tick-Associated Rash Illness (STARI)
STARI presents with a rash similar to Lyme disease but is associated with the lone star tick.
The cause of STARI remains unclear, and its long-term implications are still being studied.
Why These Infections Are Often Missed
Many tick-borne diseases share overlapping symptoms, including fatigue, fever, headaches, and joint pain.
Testing is often limited or unavailable, particularly for newer or emerging infections.
As a result, patients may be told their symptoms are not explained by current testing—or that there is nothing more that can be done.
Clinical Perspective
Tick-borne diseases extend beyond Lyme disease and may not always be detected with standard testing.
When symptoms persist after tick exposure, clinicians may need to consider a broader range of infections.
Negative tests do not always rule out tick-borne illness—especially when symptoms continue to evolve.
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
