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New Study Finds Lyme Bacteria Survive a 28-day Course of Antibiotics When Treated Four Months After Infection by Tick Bite

All subjects treated with antibiotics were found to have some level of infection 7–12 months post treatment.Despite testing negative by antibody tests for Lyme disease, two of 10 subjects were still infected with Lyme bacteria in heart and bladder. Lyme bacteria which persist are still viable.

Portola Valley, California, Dec. 13, 2017—Bay Area Lyme Foundation, a leading sponsor of Lyme disease research in the US, today announced results of two papers published in the peer-reviewed journals PLOS ONE and American Journal of Pathology, that seem to support claims of lingering symptoms reported by many patients who have already received antibiotic treatment for the disease.

Based on a single, extensive study of Lyme disease designed by Tulane University researchers, the study employed multiple methods to evaluate the presence of Borrelia burgdorferi spirochetes, the bacteria that cause Lyme disease, before and after antibiotic treatment in primates.  The study also measured the antibody immune response to the bacteria both pre- and post- treatment, as this is how current diagnostics typically evaluate Lyme disease in humans.

The data show that living B. burgdorferi spirochetes were found in ticks that fed upon the primates and in multiple organs after treatment with 28 days of oral doxycycline.  The results also indicated that the immune response to the bacteria varied widely in both treated and untreated subjects.

It is apparent from these data that B. burgdorferi bacteria, which have had time to adapt to their host, have the ability to escape immune recognition, tolerate the antibiotic doxycycline and invade vital organs such as the brain and heart, said lead author Monica Embers, PhD, assistant professor of microbiology and immunology at Tulane University School of Medicine.

In this study, we were able to observe the existence of microscopic disease and low numbers of bacteria, which would be difficult to see in humans but could possibly be the cause of the variable and nonspecific symptoms that are characteristic of post-treatment Lyme disease syndrome. Although current antibiotic regimens may cure most patients who are treated early, if the infection is allowed to progress, the 28-day treatment may be insufficient, based on these findings, Embers said.

The findings also demonstrated:

  • All subjects treated with antibiotics were found to have some level of infection 7-12 months post treatment.
  • Despite testing negative by antibody tests for Lyme disease, two of 10 subjects were still infected with Lyme bacteria in heart and bladder.
  • Lyme bacteria which persist are still viable.

To better elucidate previous animal studies demonstrating that some B. burgdorferi bacteria survive antibiotics, the study explored Lyme disease infection in rhesus macaque primates treated with antibiotics and a control group who were also infected but not treated. This species has been shown to demonstrate a progression of Lyme disease most similar to humans, particularly related to erythema migrans, carditis, arthritis, and neuropathy of the peripheral and central nervous systems.

Clearly, some medical practices governing diagnosis and treatment of Lyme disease should be reconsidered in light of this study. This study shows that we must reevaluate the current paradigm of antibody response tests for diagnosis and move away from the one size fits all approach to Lyme treatment, said Wendy Adams, Research Grant Director, Bay Area Lyme Foundation. Every day, patients with Lyme disease are told their symptoms cannot be caused by Lyme, because they test negative on antibody tests or because they have received a single course of antibiotics. More research and funding are imperative.

In the study, ticks carrying B. burgdorferi spirochetes fed on ten primates. Four months post infection, half of the primates (five) received the antibiotic doxycycline orally for 28 days at a proportional dose to that used in human treatment.  Five subjects were treated with placebo and all ten were evaluated by more than five different diagnostic methods to characterize any remaining infection. The researchers used several important techniques, including xenodiagnoses, to determine if the spirochete bacteria persisted.

The results show:

  • Few subjects displayed a rash. Although all subjects were infected, only one of the 10 displayed a rash with central clearing, the classical bulls-eye rash. The subject that developed this rash, interestingly, never mounted an immune response to five borrelia antigens throughout the study period, prior to and following treatment.
  • Organs may be infected even if antibody tests are negative. One subject which tested negative for B. burgdorferi by skin biopsy cultures, PCR and in vivo cultures, was found to have B. burgdorferi infecting the heart. Another untreated subject, who was ultimately shown to have residual Lyme bacteria in the bladder, showed a decrease in immune response over the course of infection, with a negative xenodiagnosis test in the late stage, which would signal that the animal self-cured.
  • Intact spirochetes were found in three of five treated and four of five untreated subjects based on xenodiagnosis results 12 months after the tick bite.
  • Immune responses to B. burgdorferi varied greatly post-treatment, with one subjects antibody levels dropping to pre-bite levels for three antigens while another subject experienced elevated antibodies for the same antigens throughout the study period. This is significant because it demonstrates that subjects infected with the same strain of B. burgdorferi may have different immune responses to the same antigen. And, because humans, like primates, are genetically diverse, it underscores that testing antibody responses may be inherently unreliable as a singular diagnostic modality for Lyme disease.
  • Widespread and variable microscopic disease was observed in all infected subjects, despite antibiotic treatment.  Compared to uninfected subjects of the same age, infected subjects in this study (treated and untreated) demonstrated Inflammation in and around the heart, in skeletal muscles, joints, and the protective sheath that covers the brain, and near peripheral nerves.
  • Rare, but intact B. burgdorferi spirochetes were found in the tissues of both the treated and untreated subjects. In two subjects treated with doxycycline, multiple Lyme bacteria were observed in the brain tissue. Others organs in which the spirochetes were observed included the heart, joints, bladder, skeletal muscle and adjacent to peripheral nerves.

About Lyme disease
One of the most common infectious diseases in the country, Lyme disease is a potentially disabling infection caused by bacteria transmitted through the bite of an infected tick to people and pets. If caught early, most cases of Lyme disease can be effectively treated, but it is commonly misdiagnosed due to lack of awareness and unreliable diagnostic tests. There are about 329,000 new cases of Lyme disease each year, according to statistics released in 2015 by the CDC. As a result of the difficulty in diagnosing and treating Lyme disease, as many as one million Americans may be suffering from the impact of its debilitating long-term symptoms and complications, according to Bay Area Lyme Foundation estimates.

About Bay Area Lyme Foundation
Bay Area Lyme Foundation, a national organization committed to making Lyme disease easy to diagnose and simple to cure, is the leading public foundation sponsor of innovative Lyme disease research in the US. A 501c3 non-profit organization based in Silicon Valley, Bay Area Lyme collaborates with world-class scientists and institutions to accelerate medical breakthroughs for Lyme disease. It is also dedicated to providing reliable, fact-based information so that prevention and the importance of early treatment are common knowledge. A pivotal donation from The LaureL STEM Fund covers all overhead costs and allows for 100% of all donor contributions to Bay Area Lyme Foundation to go directly to research and prevention programs. For more information about Lyme disease or to get involved, visit or call us at 650-530-2439.

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Tara DiMilia
Phone: 908-884-7024

20 Comments on “New Study Finds Lyme Bacteria Survive a 28-day Course of Antibiotics When Treated Four Months After Infection by Tick Bite

  1. I do not know how long I have had Lyme disease never had bullseye rash, but when my knee swelled up like a balloon I tested positive for Lyme disease. This was after being told by 2 emergency room physicians that it was arthritis (“ice it”). After being on doxy twice and knee re-swelling and then bursitis in elbow (Lyme disease). Went to Lyme literate doctor. What a joke. Was on 3 different antibiotics and magnesium injections and B12 injections. After 1 year did not feel any better. My bank account was empty about 2000 dollars per month for visits insurance would not cover. When my money was gone, he did not want to see me anymore. Be VERY careful with “Lyme literate” doctors.

  2. About 3 months ago I believe I contracted Lyme disease while visiting in Massachusetts, where I previously lived and where I contracted Lyme disease on three other occasions and was treated early because of the typical Lyme bullseye rash. This time, I missed seeing a rash but began to have symptoms about two months ago. Headaches, fatigue, and severe brain fog have been constant. Joint pain comes and goes. I haven’t noticed any heart issues. I have multiple autoimmune issues, however. I had been doing exceptionally well right before the symptoms started, I finally convinced a doctor in my new home, Mississippi, to test me. It came back negative, with exactly the same “equivocal” result I always have, not exactly negative, but not positive, and I have not been treated and won’t be, unlike in Mass., where they go ahead and treat based on the rash and symptoms. It will take months to get an appointment in Boston but that is my next course of action. In the meantime, I am treating myself with grapefruit seed extract, and hoping I am not causing myself harm.

    1. If you didn’t get an appointment yet for treatment, download Doctor On Demand app. It’s an online urgent care. You can find a MD specialist from a state that knows about Lyme who can diagnose you and help get you your doxycycline immediately. You don’t have to wait.

      I’m from south Florida and I had the same thing happen. The doctor down here called it a “spider bite.” That “spider bite” took me for a hell of a ride just like you. Because it was not a spider bite, it was a classic tick bite with bullseye rash and I got Lyme. Thankfully I took a picture of it, and a doctor who was from a state that knows about Lyme said that it was a classic Lyme rash. Too bad I got this far into it.

      Been on Doxycycline for 10 days now and will be until 28 days. Still going through symptoms like you, but it is getting much better with antibiotics. I’m sorry there is so much ignorance regarding this [disease] in certain states.

  3. 6 weeks ago I got the bulls-eye rash, but with no other symptoms. Went to the doctor who said it looks like a spider bite and sent me home empty handed. Last week, I went back to the doctor for a strange itchy skin rash spreading over all my body. He prescribed Doxycycline. That night I started feeling sick, and was admitted to the hospital with fever and a spreading, intensifying rash. All tests came back negative, but the ID doctor diagnosed Lyme due to a picture I had of the bulls-eye rash. He prescribed a 2 weeks of Doxy of which I convinced him to do 4 weeks. It’s been a week now and I have developed joint pain, days after already being on Doxyccycline. Maybe its the Herzing effect, or maybe the bacteria is still disseminating. My understanding is that Doxy doesn’t kill the bacteria, it prevents growth.

    Here is what I don’t understand. If Amoxicillin kills bacteria and Doxycycline prevents growth of new bacteria, and Lyme has a lifespan of 28 days then why not use Amoxicillin to kill the bacteria, instead of letting them disseminate further into the body where can morph into cysts or hide in biofilms and reproduce there? I am not a scientist or microbiologist, but its seems like a reasonable thought.

    1. Pat,
      I am family practice physician and I have encountered a number of Lyme-infected patients. As I am learning more about Lyme disease on a weekly basis, when I encounter a patient with a recent tick bite or the signs of Lyme disease, I use 3-f medications at a time; doxycycline I feel should never be used as a standalone drug. While helpful, it just isn’t strong enough. I combine doxy with rifampin and bactrim as they are bilfilm busters and the triple antibiotic treatment has a better chance of destroying Lyme. I will admit sometimes use of these meds for two months may need to happen. Good luck with your treatment.

  4. I found an engorged deer tick on my back. My skin had an immediate response to the bite upon removal, swelling up and blistering, and a rash quickly formed, though not in the style of a bullseye. I immediately went to the doctor the day after the bite and was put on 3 weeks of 100mg of doxycycline. Interestingly, I was already on 10 days of doxy and was ending that round when I found the tick bc I had a cellulitis on my leg. So the three weeks is an extension of that 10 days for a total of 31 days. My question, if the tick did have Lyme and could transfer it to me, what are the odds that I would get Lyme being on doxy at the time of transmission and then staying on it for another 21 days? I have been experiencing symptoms like headache, loss of appetite and nausea but that could be bc of the doxy or even all of this anxiety that I may have gotten Lyme disease.

    1. Hi Shannon, Unfortunately we are not a clinical organization and cannot comment on individual cases. We would advise you to continue to monitor your symptoms and to consult with your physician. Best wishes.

  5. I’m curious since you mentioned Borrelia don’t like high oxygen environments is ozone therapy considered an effective treatment?

    1. Thank you for your question. Because Bay Area Lyme is not a clinical organization, we do not opine on specific treatments or appropriate therapy. Ozone therapy is one of several alternative treatment protocols that has advocates but we are not aware of any definitive scientific research validating its effectiveness against Lyme as of this time. There are numerous testimonials and enthusiastic proponents who champion the promise of these treatments both for the regenerative and antimicrobial effects and there is a history of use in many other countries outside of the US but you are best advised to speak with your health care provider or clinician for more advice about the relevance of such an approach. Best wishes

    1. Thanks for your question.

      Quoting from the PLOS One article:

      “Persistence of B. burgdorferi was evaluated using xenodiagnosis, bioassays in mice, multiple methods of molecular detection, immunostaining with polyclonal and monoclonal antibodies and an in vivo culture system. Our results demonstrate host-dependent signs of infection and variation in antibody responses. In addition, we observed evidence of persistent, intact, metabolically-active B. burgdorferi after antibiotic treatment of disseminated infection and showed that persistence may not be reflected by maintenance of specific antibody production by the host.”

  6. I am 82 years old man with relatively good health.Last year my dr. ordered MRI of the brain for hormone deficiency. Just two days after that test, I started having running nose and mucus on my chest which never went away. My PCP after 6-month suffering ordered a blood test which came back positive for Lyme. I am not an outdoor person.

    After I took 28 days of Doxy antibiotic I saw no difference in my condition. Then she ordered Amoxy 500 Mg for 10 days and still suffering from a running nose and hoarse voice. Please advise me what I have to do. I am suffering from an allergy syndrome which my PCP thinks it is related to Lyme disease.

    1. Unfortunately Bay Area Lyme is not a clinical organization so can not advise patients individually but we would strongly encourage you to continue to consult your physician. Unfortunately you need to self-advocate. An entrenched Lyme infection can be challenging to fight. You may want to consider a specialist who is familiar with Lyme disease and can find local referrals in your area on the ILADS physician directory service. So sorry to hear of your suffering. We hope you find help and relief soon.

  7. I was bit[ten] by a tick with Lyme 2 years ago and had the tell-tale bullseye rash. First, I got really sick like the flu with extreme neck stiffness and joint and muscular pain. Then my husband found the rash on my back, thankfully. Grant it, if I remember correctly, I hit only some markers on the Elisa but I was tested early within the first few weeks. By the way, the NP who saw me for an urgent appointment classified the rash as Focal Cellulitis (showing how little our new age health care system teaches about the disease). Regardless, I talked to her about the knowledge I have on Lyme since I am an avid outdoors person and she was willing to give me doxicycline (sp?) for 28 days. Now, two years later, the little buggers have come back full force with no known ‘new’ tick bite or rash.

    I have an excellent primary care doctor who knows I don’t mess around when I complain of pain or symptoms and he values my opinion as I work in health care as well. He tested me for Lyme, both Elisa and Western Blot, and both came back positive (WB for iGg and IGm). I was diagnosed with late stage Lyme – neurological issues, joint issues, and am now having heart symptoms. I am worried.

    Anyhow, my point being, he consulted with an infectious disease doctor and I saw a neurologist and all agree I need four weeks intravenous antibiotics, then reassess. It’s been about a week with no insurance approval that I am aware of – if so I would have received the call to insert the PICC line. I did have a lumbar puncture so maybe they want those results first. Insurances can be a pain in every facet of illness these days. I hope I don’t have to fight this, for we all are in agreement that the longer we wait the more the damage will be. Maybe I am being prematurely worried though. But it breaks my heart to hear others stories with Lyme and how insurance won’t cover treatment. It is the toughest thing I have ever endured (or close to it) having to get myself up and to work everyday so I can keep my insurance. I am hopeful IV antibiotics do the trick.. this time. Which brings up another issue – the controversy is apparent of whether the healthcare field sees this as a ‘new infection’ or the same infection that didn’t get eradicated the first time and went dormant until now. All the while doing damage possibly. I believe the latter. I know myself and it explains the longer term damage. Why won’t the CDC develop further research on this before it becomes an epidemic? I know it is expensive but this gal’s tax-paying bottom would like a better excuse than that. Especially since insurances follow guidelines set by the CDC. My prayers to all those affected.

    1. Hi. I was just bitten by a deer tick in May. It was like the end of the first week and I had a welt from the bite so I went to the ER and they were packed and so I figured I’d try the urgent care. Well, they saw I had a bullseye on my back and it was right behind my heart. I took the doxycycline for three weeks and it seemed like it wasn’t doing anything and I was getting chest pains of and on so I went back and they gave me an EKG x-ray of my heart and blood test. Said i was clean, I figured it was normal.

      I had real bad chest pain three days ago went to the ER. They are so stupid sorry their good-for-somethings. They ran all the tests again and before I went in I ate like three whole garlic — total of I would say 20 cloves — and my chest pain was going away at the ER because they didn’t give me anything. What ever happened to caring for people and helping them? We only have god to help us now ’cause its all about the money, but I’ve been eating garlic for three days now and my pains went away. I’ve been reading up on Lyme and people doing garlic and getting rid of it so it’s up to you but that’s what I did.

      Hope you get better.

  8. Thanks for your work with Lyme disease. I was first tested in 2003 because I had a circular rash on my leg. The result was negative for Lyme. In 2012, I had another rash on my leg and this time the result was an 8 on the Western Blot test for Lyme AB. I took doxy for 4 days and couldn’t tolerate the nausea so I took amoxycycline. In 2014, 2015, 2016, 2017, the test result was about .5. My doctors tell me that I will always have this in my system, but I can’t blame my symptoms of fatigue, joint pain on Lyme. Please explain.

    1. Unfortunately, there is much controversy surrounding Lyme disease, particularly around the persistence of symptoms post-treatment. Typically when caught and treated early, Lyme disease can be eradicated successfully with an appropriate course of antibiotics. However, some patients continue to experience symptoms even after treatment (estimates range up to 20% of patients) and symptoms can linger for months or even years. This condition is typically referred to as Post-Treatment Lyme Disease (PTLD).

      Some doctors will advocate continued antibiotics for PTLD, however, others cite concerns about the safety of long-term antibiotic therapy and argue that there is no definitive evidence that the persistence of the symptoms is due to residual bacteria (a situation complicated, in part, due to the inadequacy of current (indirect) diagnostic tools which measure the body’s response to the pathogen, rather than the pathogen itself). There is also no good data that says continued positive tests are just a result of previous infection and doctors can not assure whether it is a residual or a new infection anyway.

      In short, you may wish to consult a physician familiar with Lyme disease for more counsel. You may wish to refer to the International Lyme and Associated Diseases Society (ILADS) physician directory for referrals in your area. Best wishes.

  9. My daughter has been disabled by Lyme for several years. Her former employer’s disability carrier, UNUM, has stopped her benefits. The mental, physical and financial burdens have been horrific. She lives in VT. Do you know of any class action lawsuits she might join, especially in light of these new findings?

    Thank you for all you do. I will become a donor shortly.

    A friend of mine has a step-grandson whose blood was treated by dialysis and purified under a study the grandson says was at MGH Boston and “cured of Lyme.” I inquired and could not find the study at MGH. Supposedly Stanford was involved. Do you know anything about this study? Are you involved?

    1. Thanks for your comment. We are so sorry that your daughter and family have been hit by Lyme disease. We know how difficult it is in so many ways – financial, emotional, physical.

      There is currently a federal antitrust lawsuit against the large insurers that was filed in November 2017 and is still pending. You can find out more about it here. There are also some efforts on facebook trying to pull together community members interested in pursuing class-action but it is not an area of focus for Bay Area Lyme Foundation, whose primary mission is to support new scientific research for the diagnosis, treatment, and cure of Lyme disease.

      Regarding the treatment, there is no clinical trial for Lyme at MGH using the method you describe (which sounds like plasmapheresis) that we are aware of and this approach would probably not be advisable as Borrelia typically avoid the blood stream where there is too much oxygen for them. Your friend may be talking about intravenous immunoglobulin (IVIG) infusions, which are sometimes used by doctors specializing in tick-borne diseases (TBD). The method may be listed for some other indication — for autoimmune disease, for example.

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