Most horses in the Mid-Atlantic region show evidence of exposure toBorrelia burgdorferi, the bacterium that causes Lyme disease. The majority of exposed horses do not develop clinical signs of disease. However, a small number of infected horses will develop disease of the nervous system, termed Lyme neuroborreliosis.
Diagnosis of equine Lyme neuroborreliosis is often elusive and the disease provokes more questions than answers: What signs do horses with Lyme disease show? What test can be used to diagnose the disease? How should test results be interpreted?
… “This study demonstrates the poor reliability of diagnostic tests for Lyme neuroborreliosis in horses. Whether negative or positive in blood or CSF tests, a horse could have Lyme disease.” [CanLyme Note: The same applies to humans.]