The CDC recommends a two-tier testing process. What’s more, if a patient tests too early after a tick bite, his or her body may not have produced enough antibodies to show up on a test with suboptimal sensitivity. This, in turn, can affect the ability to detect antibodies from patients’ blood. These tests tend to use lysed BB cultures, and therefore, depending on the culture conditions, some antigens are over-expressed, and some are under-expressed. The ELISA and Western blot are not sensitive enough.Īnother major limiting factor of the traditional ELISA and Western blot is the quality.californiensis, or European species – are at risk of receiving false negatives and missing the chance to treat their diseases. With such limited tests, patients infected with non-B31 species and strains – e.g., B. Thus 29 of the 43 patients tested negative on Western blots – i.e., the Western blot totally missed their infections with strains other than Bb ss B31 and 297. 43 patients were seropositive on the ImmunoBlot, and 14 were positive on standard Western blots prepared from a mixture of two species for Bb ss B31 and 297. In one internal study (PDF) designed to test the validity of the IGeneX ImmunoBlot against traditional Western blot tests, a total of 132 patients were tested by both Lyme Western blots and Lyme IB. This means that those tests are missing infections caused by other strains and/or species of Lyme borreliae. Many ELISA and Western blot Lyme disease tests are only equipped to detect one strain of one species of Borrelia : Borrelia burgdorferi B31 ( Bb ss B31). If a patient is infected with a species or strain of Lyme borreliae that their test can’t detect, they will get a false-negative test result and thus risk missing their diagnosis. Therefore, tests must be targeted to these multiple species and strains in order to be able to detect them. There are multiple species and strains of Lyme borreliae (Lb). Lyme disease is caused by the spiral-shaped bacteria Borrelia. Traditional Lyme disease tests are not specific enough.The limitations of the ELISA and Western blot For test results to be positive, a specific combination of bands on the membrane strip must be present. When an antibody reacts with an antigen on the strip, that band will turn dark purple. In the case of the Western blot, for example, antigens are separated by size and then transferred onto a membrane strip. These Lyme disease tests allow physicians to visualize the reaction between antibodies in an infected person’s blood to specific antigens or parts of the bacteria that cause Lyme disease. The two most common diagnostic tests for Lyme disease are the enzyme-linked immunosorbent assay (ELISA) and the Western blot. These tests are indirect, meaning they don’t detect the infecting bacteria or its antigens but rather the antibodies an infected person’s body produces in response to these antigens. Though several types of tests do exist for the diagnosis of Lyme disease, the best tests for a Lyme disease diagnosis (and those recommended by the CDC) are blood tests, also known as serological tests. When the disease isn’t caught in time, it can spread throughout the body and cause chronic health problems that could otherwise be avoided with earlier detection and treatment. Without access to the best tests for Lyme disease, it’s impossible to diagnose this treatable disease in a timely manner. One of the biggest challenges of fighting Lyme disease is providing patients with accurate diagnostic tests. The Centers for Disease Control and Prevention (CDC) estimate that there are 400,000 cases of Lyme disease annually, making Lyme a serious public health concern that only stands to grow as the spread of ticks affects disease endemicity and seasonality. Lyme disease is a tick-borne illness spread by Lyme borreliae bacteria which includes, but is not limited to, Borrelia burgdorferi sensu stricto.
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