 The Lyme Disease Research Center at Johns Hopkins is currently enrolling participants 18 and older with acute Lyme disease at Green Spring Station in Lutherville. To be eligible, you have to currently have a rash suspicious of Lyme disease that is two inches in diameter or larger. This study is observational and does not change your treatment. The study follows participants for five visits over a one-year period. To learn more, please call 410-870-5950.