Lyme disease is a disease that is caused by four main species of bacteria, including Borrelia burgdorferi, which are transmitted to humans by ticks. The disease has been difficult to detect in those affected. About sixteen US states are areas where there is a 'high incidence' of Lyme disease, according to the Centers for Disease Control and Prevention, including states in the northeast north of Virginia, as well as Wisconsin and Minnesota. Authorities are anticipating a rise in the rate of Lyme disease this year because so many people spent time outdoors during the pandemic.
Reporting in Frontiers in Microbiology, scientists have now devised a test that is sensitive enough to detect Lyme disease at its early stages, and it can distinguish between the early and late stages of the disease. The researchers created this test by focusing on identifying genetic material that escapes from the bacterial cells that cause the disease, instead of the bacteria itself, which can be hard to find and challenging to detect during the infection's early stages. For this new assay, it only takes one bacterial cell in a 0.3 milliliter blood sample to return a positive test. Typically, people with Lyme carry one to 100 bacterial cells in about a milliliter of blood.
"Early diagnosis of Lyme disease is absolutely vital in reducing suffering because early Lyme can be treated, but late Lyme is very difficult to treat," explained lead study author Dr. Jinyu Shan of the University of Leicester. "Current tests cannot typically detect the low numbers of bacteria in early-stage patient blood samples. Our goal was to design a highly sensitive test to help doctors to identify Lyme disease as early as possible."
The diagnostic tool was validated with groups of healthy people and individuals with Lyme disease in both the early and late phases of their disease. The test is now the first to positively differentiate between the disease stages.
"The test could also be very useful in rapidly ruling out someone with suspected Lyme disease," noted Shan.
Lyme disease is now the most common tick-borne infection in the United States, affecting about 500,000 people a year. Besides the tell-tale bull's eye rash, it can also cause joint pain and fever, and if left untreated, can cause paralysis and may be fatal. Early diagnosis is important, and this test may help with that.
While more work will be needed before the technology reaches the clinic, this approach could also be useful in the detection of other types of bacterial infections, suggested the researchers.
"We are currently working with a commercial partner, and investigating regulatory issues and the potential for a clinical trial for this technology," said Shan.
Sources: AAAS/Eurekalert! via Frontiers, CDC, Frontiers in Microbiology
