Confirmation of Borrelia burgdorferi sensu stricto and Anaplasma phagocytophilum in Ixodes scapularis, Southwestern Virginia.

To determine the prevalence of Borrelia burgdorferi and Anaplasma phagocytophilum in a newly established population of Ixodes scapularis in the mountainous region of southwestern Virginia, questing adult ticks were collected and the identity and infection status of each tick was confirmed by PCR and sequencing. A total of 364 adult ticks were tested from three field sites. B. burgdorferi sensu stricto was identified in a total of 32/101 (32%) ticks from site A, 49/154 (32%) ticks from site B, and 36/101 (36%) ticks from site C, for a total prevalence rate of 33% (117/356). In addition, A. phagocytophilum was detected in 3/364 (0.8%) ticks, one from site A and two from site B. The prevalence of both pathogens in ticks at these sites is similar to that reported from established endemic areas. These data document the presence of I. scapularis and the agent of Lyme disease in a newly established area of the Appalachian region, providing further evidence of range expansion of both the tick and public and veterinary health risk it creates.