Ask the Lyme doc: Can you get Lyme disease more than once?
Patients often ask whether a person can become immune to Lyme disease or whether you can get Lyme disease more than once.
In 2014, a small study found that some people may, in fact, develop strain-specific immunity to Borrelia burgdorferi, the bacteria causing Lyme disease. “Once infected with a particular strain of the disease-causing bacteria, humans appear to develop immunity against that strain that can last six to nine years,” the authors wrote. 
However, they also pointed out that at least 16 different strains of the Lyme disease bacterium have been shown to infect humans in the United States, so being bitten by a tick carrying a different strain of the disease is entirely possible.
Whether a person can develop immunity to Lyme disease is still unknown. Further studies are needed. There are certainly many instances of people contracting the infection more than once or redeveloping symptoms.
Re-infected through a new tick bite
There may be several reasons for this. A person can become re-infected with a new tick bite. Nadelman and colleagues described 17 patients who were re-infected multiple times with Lyme disease. 
Lyme disease symptoms can resurface in a person who has already been treated for the infection. Findings from both animal and human studies suggest that B. burgdorferi can cause a persistent infection. [2,3] Some doctors, however, dismiss the idea of a persistent infection. 
Lyme disease co-infections
Lastly, Lyme disease symptoms may return due to untreated co-infections. As of 2020, scientists have discovered 15 other diseases transmitted by ticks.  The list consists of viral, bacterial and parasitic infections and includes:
- Borrelia mayonii
- Borrelia miyamotoi
- Bourbon virus
- Colorado tick fever
- Heartland virus
- Powassan disease
- Rickettsia parkeri rickettsiosis
- Rocky Mountain Spotted Fever (RMSF)
- STARI (Southern Tick-Associated Rash Illness)
- Tick-borne relapsing fever (TBRF)
- 364D Rickettsiosis
Editor’s note: For the purposes of transparency, I’m an author on the International Lyme and Associated Diseases Society (ILADS) treatment guidelines, and I believe that symptoms can be due to a persistent infection in some patients. [6,7]
- C. E. Khatchikian, R. B. Nadelman, J. Nowakowski, I. Schwartz, G. P. Wormser, D. Brisson. Evidence for Strain-Specific Immunity in Patients Treated for Early Lyme Disease. Infection and Immunity, 2014; 82 (4): 1408 DOI: 10.1128/IAI.01451-13
- Sapi E, Kasliwala RS, Ismail H, et al. The Long-Term Persistence of Borrelia burgdorferi Antigens and DNA in the Tissues of a Patient with Lyme Disease. Antibiotics (Basel). 2019;8(4).
- Middelveen MJ, Sapi E, Burke J, et al. Persistent Borrelia Infection in Patients with Ongoing Symptoms of Lyme Disease. Healthcare (Basel). 2018;6(2).
- Shapiro ED. Repeat or persistent Lyme disease: persistence, recrudescence or reinfection with Borrelia Burgdorferi? F1000Prime Rep. 2015;7:11.
- Diseases Transmitted by Ticks. Centers for Disease Control and Prevention. https://www.cdc.gov/ticks/diseases/index.html Last accessed 12/12/20.
- Cameron D, Gaito A, Harris N, et al. Evidence-based guidelines for the management of Lyme disease. Expert Rev Anti Infect Ther. 2004;2(1 Suppl):S1-13.
- Cameron DJ, Johnson LB, Maloney EL. Evidence assessments and guideline recommendations in Lyme disease: the clinical management of known tick bites, erythema migrans rashes and persistent disease. Expert Rev Anti Infect Ther. 2014;12(9):1103-1135.
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