De. Sonenshine et al., BORRELIA-BURGDORFERI IN EASTERN VIRGINIA - COMPARISON BETWEEN A COASTAL AND INLAND LOCALITY, The American journal of tropical medicine and hygiene, 53(2), 1995, pp. 123-133
Citations number
35
Categorie Soggetti
Public, Environmental & Occupation Heath","Tropical Medicine
In Virginia, Borrelia burgdorferi was more prevalent in a site along t
he Atlantic Ocean, near Maryland, than in an inland site near Williams
burg and Yorktown. At the coastal site on Assateague Island, B. burgdo
rferi was isolated from 4.2% of 475 animals sampled, including four sp
ecies of small mammals. Serologic tests indicated that 25-37% of the s
mall rodents assayed had been exposed to B. burgdorferi. Immunofluores
cence antibody assays specific for B. burgdorferi showed spirochete in
fection in Ixodes scapularis and Dermacentor variabilis but not in oth
er species of ticks also examined from this site. At another coastal s
ite (Parramore Island), no evidence of Peromyscus leucopus was found,
no immature specimens of I. scapularis were collected, and no isolatio
ns were made from numerous raccoons or small mammals sampled. Borrelia
burgdoferi infection was found in one I. cookei nymph, but not in num
erous specimens of I. scapularis or other tick species from this local
ity. At the inland site between Williamsburg and Yorktown, B. burgdofe
ri was isolated from two small mammal species and antibodies to B. bur
gdorferi were found in only 7-10% of the small mammals sampled. Ixodes
scapularis were less abundant at this locality than at the Assateague
Island site. Borrelia burgdoferi spirochetes were found in I. scapcul
aris and a single nymph of Amblyomma americanum, but not in any of num
erous specimens of four other species. Infection with B. burgdorferi w
as found in 20% of unfed adult I. scapularis from vegetation, but in o
nly 0.2% of numerous adults from hunter-killed deer. Infection in imma
ture ticks was much lower than at Assateague Island. Borrelia burgdorf
eri may be more prevalent along the Atlantic coast than in inland area
s. Isolations, seroprevalence, immature I. scapularis densities, and s
pirochete infection rates in ticks were higher at the Assateague Islan
d site than the Williamsburg/Yorktown site. Consequently, the risk of
human exposure to Lyme disease may be higher in some parts of the coas
tal area than elsewhere in Virginia. Overall, B. burgdorferi is less i
ntense in Virginia than in the northeastern United States.