A new technique, known as xenodiagnosis, which involves use of disease-free ticks, is currently being used by researchers to check whether Lyme disease bacteria can be detected in people who continue to suffering from fatigue and arthritic symptoms even after completing antibiotic therapy.
It was well tolerated by the volunteers, but investigators could not find evidence of Lyme disease bacteria in most of the cases where enough ticks were collected to make testing possible.
Larger studies are needed, the scientists say, to determine the significance of positive xenodiagnosis results in cases where Lyme disease symptoms persist following antibiotic therapy.Adriana Marques, M.D., of the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, and Linden Hu, M.D., of Tufts Medical Center, Boston, led the pilot study. Findings appear online in Clinical Infectious Diseases
.The most common tick-borne illness in the United States, Lyme disease is caused by Borrelia burgdorferi
bacteria that are transmitted to people by ticks of the Ixodes
"Most cases of Lyme disease are cured by antibiotics, but some patients continue to experience symptoms despite the absence of detectable Lyme bacteria," said NIAID Director Anthony S. Fauci, M.D. "This poses a mystery that requires continued research into new or improved ways to diagnose Lyme disease and determine the cause of unresolved symptoms."
"Xenodiagnosis using ticks to detect B. burgdorferi
has been used previously in animal studies, but this is the first time it has been tried in people," said Dr. Marques. "Our primary goals in this initial trial were to develop procedures for tick xenodiagnosis and to determine its safety in humans."