Media Contact:
Tara DiMilia, 908-947-0500,

California Strains of Lyme Bacteria May Survive Antibiotic Treatment, According to New Study

This new study funded by Bay Area Lyme Foundation identifies 20 FDA-approved compounds that are more effective in inhibiting persistent Lyme bacteria than standard treatment

Silicon Valley, CA, April 6, 2016—A laboratory study published today, funded by the Bay Area Lyme Foundation, is the first study to demonstrate that strains of Lyme bacteria present in California ticks are able to form persister bacteria, which do not respond well to treatment.  The study is also the first to identify FDA-approved therapies that may be more effective in inhibiting these specific strains of persister bacteria in the lab than doxycycline, the most commonly prescribed treatment for Lyme disease. The study was conducted by Stanford School of Medicine researchers and published in the Open Access publication Drug Design, Development and Therapy. View full study here:

“Many Lyme disease patients experience symptoms after treatment, and this study appears to help us understand why this may happen,” said Bonnie Crater, Vice President and Science Committee Chair, Bay Area Lyme Foundation. “This study demonstrates the potential for effective treatment for patients with Lyme disease for whom routine antibiotics are not working.”

Antibiotic treatment for acute Lyme disease is effective in the majority of cases, however 10 to 20% of patients diagnosed with acute Lyme disease still have persistent symptoms even after a course of antibiotics, based on a study conducted at Johns Hopkins. According to Bay Area Lyme Foundation estimates, as many as one million Americans suffer from debilitating later stage symptoms of Lyme disease, including muscle and joint pain, generalized fatigue, and neurological symptoms, some of which may be associated with persister bacteria.

Led by Jayakumar Rajadas, PhD, Director, Biomaterials and Advanced Drug Delivery Lab (BioADD), Stanford School of Medicine, this new study found that doxycycline was able to inhibit only 94% of the tested bacteria. Using high throughput screening of 4,366 chemical compounds, they found that not only were more than 100 of these compounds capable of inhibiting the growth of the tested bacteria, but some were more effective than doxycycline for these strains of bacteria. Researchers subsequently selected 20 FDA-approved compounds of the 100 compounds to further test on the persister subpopulation. Among these 20 FDA-approved compounds, three of them inhibited more persister bacteria than doxycycline; these are azlocillin, gramicidin  and cefotaxime. Of note, cefotaxime is one of the World Health Organization’s List of Essential Medicines and widely used for treating many diseases. Further studies must be conducted before considering these compounds as treatment for Lyme disease.

Although some studies have shown doxycycline can completely eradicate the bacteria that causes Lyme both in vitro and in vivo, conflicting studies have shown that doxycycline cannot eliminate all of the bacteria. In fact, previous laboratory research which studied a strain of B. burgdorferi persisters commonly acquired from ticks on the East Coast, identified additional drug candidates that can more effectively eliminate those persister strains than the current antibiotic regimen used for acute Lyme disease.

About Lyme disease

One of the fastest growing vector-borne infectious diseases in the United States, Lyme disease is a potentially debilitating 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 approximately 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 nonprofit organization committed to making Lyme disease easy to diagnose and simple to cure, is a leading private sponsor of innovative Lyme disease research in the US.  A national 501c3 nonprofit organization based in Silicon Valley, the Foundation 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 Foundation covers all overhead costs and allows for 100% of all donor contributions to Bay Area Lyme Foundation to go directly to research programs. For more information about Lyme disease or to get involved, visit or call us at 650-530-2439.

# # #

2 Comments on “California Strains of Lyme Bacteria May Survive Antibiotic Treatment, According to New Study

  1. Thank you! Thank you! Thank you! for your research Dr. Rajadas! We are all anxiously awaiting better treatment for our debilitating symptoms. Can’t wait to try Azlocillin.

Leave a Comment

Your email address will not be published. Required fields are marked *