Field Studies on Lyme Disease in North America

Abstract

The primary tick vector of Borrelia burgdorferi in eastern and central North America is Ixodes dammini; in western North America, Ixodes pacificus. Searching for the appropriate vector is the first step in determining whether a region is endemic and enzootic for the spirochete B burgdorferi, the etiological agent of Lyme disease, followed by examination of the ticks (questing or already attached to hosts) and wildlife for the spirochete. Questing ticks can be collected through a variety of methods. The two major animal hosts for I dammini are the white‐footed mouse Peromyscus leucopus and the white‐tailed deer Odocoileus virginianus. Sampling strategies should consider habitat and season. All three life stages of the vector tick should be located, indicating a self‐sustaining population. Although B burgdorferi can be detected in many ways, there is no substitute for isolating the spirochete in Barbour‐Stoenner‐Kelly II medium for definitive proof of the presence of the Lyme disease spirochete.