Mold Illness & Lyme Disease The Connection Between Mold Illness and Lyme Disease Chronic fatigue. Joint pain. Brain fog. Neurological symptoms. Hormonal shifts. Immune dysfunction. These symptoms are commonly reported in both mold-related illness and Lyme disease — and for many individuals, they do not occur in isolation. Mold exposure, particularly in water-damaged buildings, can lead to illness driven by mycotoxins. Lyme disease, caused by the bacterium Borrelia burgdorferi