A Ten-Year Study of Tick Biting in Mississippi: Implications for Human Disease Transmission

To determine exactly which tick species bit people in Mississippi, information was gathered on ticks involved in human biting cases for the ten-year period, January 1, 1990-December 31, 1999. Specimens were identified by the author and, in most cases, confirmed by personnel at the Institute of Arthropodology and Parasitology, Georgia Southern University. A total of 119 ticks were recovered from 73 humans during the study period. Seven tick species were represented; most common included the lone star tick, Amblyomma americanum, the gulf coast tick, A. maculatum, the American dog tick, Dermacentor variabilis, and the black-legged deer tick, Ixodes scapularis. Interestingly, no immature Ixodes scapularis were collected. there were several unusual records. Twelve larvae of Amblyomma tuberculatum, a species associated with the gopher tortoise, were removed from a patient. Two Dermacentor albipictus larvae were collected from an elderly woman with no travel history except her backyard. One Dermacentor sp. nymph, removed from a man in central MS, was not even a North American species. One adult female Dermacentor variabilis was involved in a clinical case of tick paralysis. These findings indicate that, although we know which tick species are common human biters, unusual/unreported tick-human interactions may be more common than we think.