medlineplus.gov/ency/article/001319.htm Encyclopedia: Lyme Disease MedLine Plus Lyme Disease MedlinePlus Encyclopedia: Lyme Disease medlineplus.gov/ency/article/001319.htm Lyme disease Stage 1 Lyme disease three stages MedlinePlus, “Lyme Disease” Stage 3 National Library of Medicine (Lyme Disease) Medline Plus, Lyme Disease Stage 2 Lyme disease