NEW Discovery for Antibiotic Resistance

A new University of Copenhagen study reports a previously unknown hiding place for the genes that make bacteria resistant to antibiotics. The prevailing belief that resistant bacteria will lose their resistance genes during a break from antibiotic use has been challenged by the findings of this new study. 

This study shows that resistance genes have the ability to hide in inactive bacteria, where they form a hidden reserve of resistance that bacteria can rely on, even in the absence of antibiotics. The new study shows that biofilms contribute to antibiotic resistance of bacteria where inactive bacteria layered deep in the biofilm maintain their resistance even when dormant. These findings are important to understanding how bacterial antibiotic resistance takes place, as resistance genes have been found to persist longer than previously believed.  

Read the full University of Copenhagen News Article here

Read the full text Danish study article here

Read more LDA articles on bacteria persistence here

Lyme and Tick-Borne Diseases

In this section, you can find information on Lyme disease caused by Borrelia bacteria and other tick-borne diseases (TBD) and conditions which can be caused by a number of organisms.  Currently there are about 20 different TBD.  Different types of ticks can transmit different diseases, and one tick bit can also transmit more than one disease. Diagnosis and treatment are difficult processes. The LDA provides information on this website for educational purposes and does not provide medical or other professional advice. 

This section contains aspects of Lyme/TBD  related to the diseases; tick vectors; prevention; COVID 19 & Lyme; pets and Lyme, kids & schools & Lyme. There is also a section of photos of rashes, organisms, and ticks.  Check the drop down menu for all the options. 


What Is Lyme Disease?

Lyme disease in the US is caused by a spiral-shaped bacteria, Borrelia burgdorferi (Bb), or by newly discovered Borrelia mayonii. It is usually transmitted by the bite of an infected tick−Ixodes scapularis in the East, Ixodes pacificus in the West.   

Lyme disease bacterium

How is Lyme disease transmitted?
In the USA, the bacteria are transmitted to people and animals by the bite of an infected tick, Ixodes scapularis, (commonly called the blacklegged or deer tick), and Ixodes pacificus (western blacklegged tick) in the West. Although other types of ticks such as the Dermancentor variabilis (American dog) and some insects have been shown to carry the Lyme bacteria, to date, transmission of Lyme through those vectors has not been proven.  The longer a tick is attached, the greater risk of disease transmission.

The Lyme bacteria has been proven to survive blood banking conditions; however, to date, no transmission has been proven through blood transfusions in humans. Studies have shown transmission through this route in mice in the lab. Note: Other tick-borne diseases have been transmitted through the blood supply.
The bacteria can also be passed through the placenta of a pregnant woman to the fetus—congenital transmission. The DNA of the bacteria has been found in breast milk, but no transmission has been proven to date in humans.
There is no proof to date that Lyme is sexually transmitted, although some preliminary studies have found PCR positives for the DNA of the Lyme bacteria in semen and in cervical tissue. These findings do not prove sexual transmission, but some physicians feel because the Lyme and syphilis spirochete (bacteria) are similar, Lyme may be sexually transmitted.

LDA World Covered in Ticks 2017

Lyme disease is found in approximately 80 plus countries worldwide, and 50 states in the USA, although different types of ticks and different strains of bacteria may be involved. In the USA the number of new cases of Lyme disease contracted each year is approaching 400,000. Many of those cases will include co-infections. 

Lyme Colon Biopsy

Where can Lyme disease be found in the body? 
Lyme is a multi-systemic disease, and the Lyme disease bacterium, Borrelia burgdorferi (Bb), may be found in many different organs, although it is often difficult to test for and to culture. To the left is an image that shows Borrelia burgdorferi (Bb) in the human colon.

Image Borrelia burgdorferi (Lyme disease bacterium) in the Human Colon. Courtesy of Martin Fried, MD.
© LDA.  2015, 2016, 2020. This website provides practical and useful information on the subject matters covered. It is distributed with the understanding that LDA is not engaged in rendering medical or other professional services. Seek professional services if necessary.

Borrelia burgdorferi in the Alzheimer’s Brain

In a newly published article in the IOS Press, researchers identified the Borrelia burgdorferi spirochete, the causative agent of Lyme disease in autopsied brain tissue of patients diagnosed Alzheimer’s. In addition, they found a significant number of Borrelia-positive aggregates with a known biofilm marker, alginate. Immunohistochemical data also showed that Borrelia-positive aggregates co-localized with amyloid and anti-phospho-tau markers.

Investigators studied patients diagnosed with either Alzheimer’s or Parkinson’s diseases. They found the presence of B. burgdorferi antigen and DNA in patients with Alzheimer’s pathology. One of the brain specimens was from a person previously diagnosed with Lyme disease. Researchers additionally infected two mammalian cell lines with B. burgdorferi which resulted in a significant increase in the expression of amyloid-β and p-Tau proteins in both cells lines post-infection. This finding further supports the potential relationship of B. burgdorferi and amyloids.

Results of the study indicate that B. burgdorferi can be found in Alzheimer’s brain tissues, in spirochete, known antibiotic resistant biofilms, and co-localized amyloid markers. These findings provide evidence for a likely association between B. burgdorferi infections and biofilm formation, Alzheimer’s pathology, and chronic neurodegenerative diseases.

Access to full article can be found here

Additional LDA Articles on Lyme & Alzheimer’s can be found here

Tick Sugar Influence on Cell Wall of Borrelia Spirochetes

Persistent Borrelia burgdorferi
Borrelia burgdorferi spirochete in mouse, Photo by Stephen W. Barthold, DVM, PhD

Nature Microbiology recently published an article where researchers identified a sugar that influences cell wall function in Borrelia spirochetes. Authors state that Borrelia burgdorferi bacteria produces glycan chains in the cell wall where MurNAc is occasionally replaced with an unknown sugar. Investigators identified that B. burgdorferi produces glycans that contain GlcNAc–GlcNAc. Chitobiose is the unusual disaccharide, or sugar, identified in the cell wall of Borrelia bacteria.

Mutant bacteria, bacteria that require a particular additional nutrient which the normal strain does not, have altered morphology, reduced motility, and cell envelope defects that researchers suspect result from producing peptidoglycan that is stiffer than that in wild-type bacteria.

Virginia Tech researchers discovered that the bacterium that causes Lyme disease has a highly unusual modification in its protective molecular bag—its peptidoglycan, which is common to all bacteria. Researchers conducted LCMS, liquid chromatography coupled with mass spectroscopy to determine that chitobiose was the actual sugar. They also conducted Nuclear Magnetic Resonance and metabolic labeling studies with C13 labeled sugars to confirm this finding. They additionally determined why this modification is found in Borrelia—it allows for elasticity which supports effective motility of the bacteria to move through tissue and cartilage. Without this modification, motility is impeded.

The change in the Borrelia bacterium is unprecedented—it’s an unusual sugar modification that is not known to occur in any other organism. One way the bacterium gets this sugar modification is from ticks. This happens by absorbing a carbohydrate unique to ticks. The alteration is specific to ticks and allows the bacterium to better move and be more likely to cause disease in hosts.

Researchers provide evidence for this model, demonstrating that bacteria that are unable to bring in chitobiose to the cells have reduced amounts of peptidoglycan, as well as altered peptidoglycan composition, which results in abnormalities in bacterial cell form and structure.

The significance of these findings is that disrupting the balance between flagellar motion and peptidoglycan structure impairs motility, which hinders bacterial movement. This finding could potentially shed light on understanding what causes symptoms and illness in humans, as well as identifying potential diagnostic and treatment strategies that target Borrelia spirochetes. 

Read the full text Nature Microbiology article here

Read additional LDA articles on Borrelia here



Lyme Disease: 19ISP mRNA Vaccine Candidate Shows Clinical Efficacy

19ISP mRNA VaccineSajid, et al., published in the journal Science Translational Medicine about the development of a promising mRNA vaccine, 19ISP, which has been found to induce tick resistance and prevent transmission of the Lyme disease-causing agent, Borrelia burgdorferi (Bb). The researchers observed that hosts with repeated exposures to the black-legged tick, Ixodes scapularis (the most prevalent vector of the Bb), can develop resistance against ticks, also referred to as “tick immunity.” The vaccine was developed to generate this same type of tick resistance. Hosts inoculated with 19ISP developed erythema at the site of tick bite which, according to the creators of the vaccine, is a sign of acquired tick resistance. This resulted in poor tick feeding and transmission of Bb was reduced. The research team puts forth 19ISP as a promising antitick vaccine candidate with the hope that it may prevent transmission of Lyme and other tick-borne diseases.

Read the study in Science Translational Medicine.

Read about other TBD vaccines.

Borrelia mayonii Spirochetes Observed on Blood Smear

B. mayonii is a relatively new species of Lyme causing pathogen that has only been detected in the Upper Midwest of the United States. It is considered a rare cause of Lyme disease and may frequently go undetected. 

Mayo laboratories recently observed that spirochetes of the pathogen Borrelia mayonii can occasionally be visualized on routine blood smears, much like spirochetes of the Tick-Borne Relapsing Fever group. B. mayonii spirochetes are found at high levels in peripheral blood, whereas B. burgdorferi spirochetes are not. This understanding may raise awareness and recognition of the Lyme disease causing bacterium, and could lead to more consistent and accurate diagnosis of this cause of Lyme disease.

Read full article here

Read more LDA articles on Lyme disease here



About Lyme Disease Symptoms

Lyme Disease Symptoms & Signs

Lyme disease symptoms can affect any system in the body and can mimic symptoms of many different diseases.

Lyme disease symptoms

Lyme Disease Symptoms Compiled by the LDA

As listed in the LDA LymeR Primer Available for online ordering

As listed in the LDA Spanish LymeR Primer Available for Downloading

Click dropdown arrows for symptoms

Lyme Disease Symptoms Compiled by the LDA

As listed in the LDA LymeR Primer Available for online ordering

As listed in the LDA Spanish LymeR Primer Available for Downloading

Click dropdown arrows for symptoms

Lyme disease symptoms
Lyme disease symptoms


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    chest pain or rib soreness, shortness of breath, heart palpitations, pulse skips, heart block, heart murmur

Lyme disease symptoms

Lyme Rash

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    Only about 9% get the classic bull’s eye rash. Others may get another type of Erythema Migrans (EM) rash or may get no rash at all. Rash at other than bite site may be disseminated disease. Symptoms may occur days or months after a tick bite.
    According to the Centers for Disease Control & Prevention (CDC) surveillance criteria, an erythema migrans (EM) rash in an endemic area, means Lyme disease. In a non-endemic area, a rash requires a positive test. The CDC criteria are for surveillance purposes, not diagnosis.



  • Click for Symptoms

    nausea or vomiting, GERD, change in bowel function (constipation, diarrhea), gastritis, abdominal cramping, cystitis, irritable bladder or bladder dysfunction, newly diagnosed irritable bowel syndrome (IBS) 



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    joint/muscle pain in feet, ankle pain, shin splints, joint pain or swelling, stiffness of the joints, neck or back, muscle pain or cramps that migrate, Temporomandibular joint dysfunction (TMJ/TMJD jaw pain), neck creaks & cracks, neck stiffness.

Neurological lyme disease


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    muscle twitching, headache, tingling, numbness, burning or stabbing sensations, facial paralysis (Bell’s palsy), dizziness, poor balance, increased motion sickness, light-headedness, wooziness, difficulty walking, tremor, confusion, difficulty thinking/concentrating/ reading, forgetfulness, poor short-term memory, disorientation (getting lost, going to wrong place), difficulty with speech, double or blurry vision, eye pain, blindness, increased floaters, increased sensitivity to light or sound, buzzing or ringing in ears, ear pain, decreased hearing, seizure activity, white matter lesions, low blood pressure.



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    mood swings, violent outbursts, irritability, depression, disturbed sleep (too much, too little, early awakening), personality changes, obsessive – compulsive disorder (OCD), paranoia, panic/anxiety attacks, hallucinations.



  • Click for Symptoms

    testicular pain/pelvic pain, menstrual irregularity, milk production (lactation), sexual dysfunction or loss of libido.

Lyme disease symptoms

Other Symptoms

  • Click for Symptoms

    fever, sweats, or chills, weight change (loss or gain), fatigue, tiredness, hair loss, swollen glands, sore throat, difficulty swallowing, swelling around the eyes, burning in feet, swelling

Lyme Transmission

Lyme Transmission

  • Click for Info

    Not all patients recall a tick bite. Studies vary as to how long the tick must be attached in order to transmit Lyme disease. The longer an infected tick is attached, the greater the chance of contracting Lyme disease. Lyme can be transmitted through the placenta.

Lyme disease symptoms

Lyme from Borrelia mayonii
Another strain of Borrelia that causes Lyme

Early symptoms: fever, headaches, rash, neck pain Later: arthritis. Difference from Borrelia burgdorferi may include nausea & vomiting, diffuse rashes, higher concentration of bacteria in blood

Symptoms reviewed by Elizabeth Maloney, MD; President, Partnership for Tick-Borne Diseases Education

Other Tick-Borne Diseases & Conditions:

Patients may also contract other tick-borne diseases (co-infections) from a tick bite along with Lyme disease.

Visit LDA website Other Tick-Borne Diseases page

Other Resources for Lyme Disease Symptoms:

Columbia Lyme Rash Poster

Dr. Joseph Burrascano’s 2005 Lyme Disease Symptom List Chart

En Espanol Enfermedad De Lyme”  Spanish Patient Intake, Printable PDF

LDA Cardiac (Heart) Poster

LDA Lyme Disease Medical Photos  Including Rashes

LDA LymeLiteracy  LDA President’s Blog

LDA “LymeR Primer™” Detailed LDA Printable Brochure

En Española – “LymeR Primer™”  Folleto de Sensibilización

ILADS Treatment Guidelines International Lyme & Associated Diseases Society

Columbia Lyme & Tick-Borne Diseases Research Center – Treatment Page Columbia University, Irving Medical Center

© LDA. 2015, 2016, 2020. This website provides practical and useful information on the subject matters covered. It is distributed with the understanding that LDA is not engaged in rendering medical or other professional services. Seek professional services if necessary.









Pregnancy, Breastfeeding & Lyme Bibliography

Any woman who has Lyme disease and is considering becoming pregnant or who is pregnant, or who is bitten by a tick during pregnancy, should see a Lyme disease doctor, one who understands the serious medical implications of Lyme during pregnancy. The Lyme bacteria, Borrelia burgdorferi, can cross the placenta and can cause death of the fetus. The Lyme Disease Association (LDA) has compiled the following list of articles related to Lyme and pregnancy and Lyme and breastfeeding for informational purposes only, for your review and review by your physician.

Project Lyme & Mothers Against Lyme Webinar – “Lyme Disease & Pregnancy: State of the Science & Opportunities for Research” featuring Holly Ahern, MS, MT (ASCP), Sue Faber, RN, BScN, & Representatives from the NIH. (2021) 

CDC Focus on Maternal-Fetal Transmission of Lyme Disease (2020)

Bale JF, Jr., Murph JR (1992). “Congenital infections and the nervous system.” Pediatr Clin North Am 39(4): 669-90.

Brzostek T. (2004). “[Human granulocytic ehrlichiosis co-incident with Lyme borreliosis in pregnant woman—a case study].” Przegl Epidemiol 58(2): 289-94.

Carlomagno G; Luksa V; Candussi G; Rizzi GM; Trevisan G Acta Eur Fertil 1988 Sep-Oct;19(5):279-81 Dept. of Obstetrics and Gynecology, University of Trieste School of Medicine. Lyme Borrelia positive serology associated with spontaneous abortion in an endemic Italian area.

Donta S, Aberer E, Ziska M. (1996). “Clinical Conference: Chronic Lyme Disease.” Journal of Spirochetal and Tick-Borne Diseases Vol.3 No.3/4 Fall Winter 1996.

Faber S. (2017). “Research findings on Lyme and Pregnancy/Congenital Transmission.” YouTube Video Retrieved from https://www.lymehope.ca/advocacy-updates/sharing-our-research-findings-on-lyme-and-pregnancycongenital-transmission-with-minister-of-health-and-public-health-agency-of-canada   The opinions presented in the video are those of the presenter and not necessarily of the Lyme Disease Association.

Gardner T. (1995). Lyme disease. Infectious diseases of the fetus and newborn infant. J. S. Remington and J. 0. Klein. Philadelphia, Saunders. Chap. 11: 447-528.

Gardner T. (2000) Lyme disease. 66 Pregnancies complicates by Lyme Borreliosis. lnfec Dis Fetus and Newborn Infant. Saunders

Goldenberg RL, Thompson C. (2003). “The infectious origins of stillbirth.” Am J Obstet Gynecol 189(3): 861-73.

Gustafson JM, Burgess EC, et al. (1993). “Intrauterine transmission of Borrelia burgdorferi in dogs.” Am J Vet Res 54(6): 882-90. (dog study)

Harvey WT, Salvato P. (2003) ‘Lyme disease’: ancient engine of an unrecognized borreliosis pandemic? Med Hypotheses. 60(5), 742-59.

Hercogova J, Vanousova D (2008). Syphilis and borreliosis during pregnancy. Dermatol Ther. 2008 May-Jun;21(3):205-9.

Jones CR, Smith H, Gibb E, Johnson L (2005) Gestational Lyme Disease: Case Studies of 102 Live Births. Lyme Times. Gestational Lyme Studies 34-36

Jovanovi R, Hajri A, Cirkovi A, et al. (1993) [Lyme disease and pregnancy]. Glas Srp Akad Nauka Med (43), 169-72.

Lakos A, Solymosi N (2010) Maternal Lyme borreliosis and pregnancy outcome. Int J Infect Dis 14(6), e494-8.

Lavoie PE; Lattner BP; Duray PH; Barbour AG; Johnson HC. Arthritis Rheum 1987; Culture positive seronegative transplacental Lyme borreliosis infant mortality. Volume 30, Number 4, 3(Suppl): S50.

Lawrence RM, Lawrence RA (2001). “Given the Benefits of Breastfeeding, What Contraindications Exist?” Pediatric Clinics of North America Volume 48, Issue 1, February 2001

MacDonald A.B. (1989). “Gestational Lyme borreliosis. Implications for the fetus.” Rheum Dis Clin North Am 15(4): 657-77.

MacDonald A.B. (1986). “Human fetal borreliosis, toxemia of pregnancy, and fetal death.” Zentralbl Bakteriol Mikrobiol Hyg [A] 263(1-2): 189-200.

MacDonald A.B., Benach J.L., et al. (1987). “Stillbirth following maternal Lyme disease.” NY State J Med 87(11): 615-6.

Maraspin, V., Cimperman J., et al. (1999). “Erythema migrans in pregnancy.” Wien Klin Wochenschr 111(22 23): 933-40.

Markowitz, L. E., Steere AC, et al. (1986). “Lyme disease during pregnancy.” JAMA 255(24): 3394-6. Because the etiologic agent of Lyme disease is a spirochete, there has been concern about the effect of maternal Lyme disease on pregnancy outcome.

Mikkelsen AL, Pa lie C. Lyme disease during pregnancy. (1987) Acta Obstet Gynecol Scand 66(5), 477-8.

Moro, Manuel H.; Bjornsson, Johannes; Marietta, Eric V.; Hofmeister, Erik K.; Germer, Jeffrey J.; Bruinsma, Elizabeth; David, Chella S.; and Persing, David H. (2001). “Gestational Attenuation of Lyme Arthritis Is Mediated by Progesterone and IL-4,” J Immunol 2001; 166:7404-7409

Mylonas I (2011) Borreliosis During Pregnancy: A Risk for the Unborn Child? Vector Borne Zoonotic Dis. 11:891-8.

Nadal D, Hunziker UA, Bucher HU, et al. (1989) Infants born to mothers with antibodies against Borrelia burgdorferi at delivery. Eur J Pediatr 148(5), 426-7. Abstract

Onk G, Acun C, Kalayci M, Cagavi F, et al. (2005) Gestational Lyme disease as a rare cause of congenital hydrocephalus. J Turkish German Gynecology Association Artemis,6(2), 156-157.

Schlesinger, P. A., Duray PH, et al. (1985). “Maternal-fetal transmission of the Lyme disease spirochete, Borrelia burgdorferi.” Ann Intern Med 103(1): 67-8.

Schutzer SE, Janniger CK, Schwartz RA (1991) Lyme disease during pregnancy. Cutis 47(4), 267-8. Abstract

Silver H. (1997) Lyme Disease During Pregnancy. Inf Dis Clinics of N. Amer. Vol 11, No 1,

Strobino BA, Abid S, Gewitz M (1999) Maternal Lyme disease and congenital heart disease: A case-control study in an endemic area. Am. J. Obstet. Gyn., 180:711-716.

Strobino BA, Williams CL, Abid S, Chalson R, Spierling P (1993)  Lyme disease and pregnancy outcome:  A prospective study of 2,000 prenatal patients. Amer J Ob Gyn, 169:367‑74.

Van Holten J, Tiems J, Jongen VH (1997) Neonatal Borrelia duttoni infection: a report of three cases. Trap Doct 27(2), 115-6.

Walsh CA, Mayer EW, Baxi LV. (2007). Lyme disease in pregnancy: case report and review of the literature. Obstet Gynecol Surv. 2007 Jan;62(1):41-50.

Williams CL, Strobino BA, Lee A, Curran A, Benach JL, Inamdar S and Cristofaro (1990) Lyme disease in childhood:  Clinical and epidemiologic features of ninety cases. Pediatr. Infect. Dis.,  9: 10‑14.

Williams CL, Strobino BA (1990)  Lyme disease and pregnancy ‑ A  review of the literature.  Contemporary Ob/Gyn, 35:48‑64.

Williams CL, Strobino BA, Weinstein A, Spierling P, Medici F (1995)  Maternal Lyme disease and congenital malformations:  A cordblood serosurvey in endemic and control areas.  Pediatric and Perinatal Epid., 9: 320‑330. 

Weber, K., Bratzke HJ, et al. (1988). “Borrelia burgdorferi in a newborn despite oral penicillin for Lyme borreliosis during pregnancy.”Pediatr Infect Dis J 7(4):286-9.


Schmidt. B. L., Aberer E, et al. (1995). “Detection of Borrelia burgdorferi DNA by polymerase chain reaction in the urine and breast milk of patients with Lyme borreliosis.” Diaqn Microbiol Infect Dis 21(3): 121-8

Altaie. S. S., Mookherjee S, et al. (1996). Abstract # I17 Transmission of Borrelia burqdorferi from experimentally infected mating pairs to offspring in a murine model. FDA Science Forum.

Pregnancy & Breastfeeding

Centers for Disease Control & Prevention (CDC) website

During Pregnancy & While Breastfeeding
“Lyme disease acquired during pregnancy may lead to infection of the placenta and possible stillbirth, however, no negative effects on the fetus have been found when the mother receives appropriate antibiotic treatment. There are no reports of Lyme disease transmission from breast milk.” http://www.cdc.gov/ncidod/dvbid/LYME/ld_transmission.htm




NIAID Webpage on Lyme Vaccines

The National Institute of Allergy & Infectious Diseases (NIAID), National Institutes of Health (NIH), has a page on Lyme vaccines including its information on what occurred with the first Lyme vaccine, LYMErix, and what is happening with some current vaccines and vaccine research.


Pfizer Gets Priority Review for Tick-Borne Encephalitis Vaccine

Pfizer has received priority review for their vaccine, TicoVac, which protects against tick-borne encephalitis. This tick-borne virus can cause meningitis and trigger long-term neurological symptoms in humans. If approved, the vaccine would potentially protect travelers and members of the United States military that are deployed to regions where the virus is common, such as Europe and parts of Asia.

TicoVac is an inactivated virus vaccine that has been highly effective at preventing tick-borne encephalitis throughout Europe for four decades. With this FDA fast-pass, it is hoped that a US approval would occur by August and would simplify the process for US military members to get the vaccine. 

Pfizer is also developing a vaccine for another tick-borne illness: Lyme disease.

Read full article here.

Read more LDA posts on vaccines here