Blood-meal analysis for the identification of reservoir hosts of tick-borne pathogens in Ireland.
The results of analysis of blood-meal remnants in unfed nymphs, despite relatively low detection levels (49.4%, n = 322), support the conclusion from an earlier study that small rodents are relatively unimportant as reservoir hosts of B. burgdorferi s.l. in this particular area, and suggest that songbirds (Passeriformes) are the most significant hosts in this respect. Tick (Ixodes ricinus) abundance was greater in the present study, but the overall Borrelia burgdorferi s.l.-infection prevalence of nymphal ticks was the same (12.2%), and the relative proportions of the various Borrelia burgdorferi s.l. genospecies were similar. B. garinii and B. valaisiana were the most frequent, B. burgdorferi s.s the least frequent, and B. afzelii of intermediate frequency. An unusually high proportion of nymphs (39%) with multiple infections of different B. burgdorferi genospecies was detected, and Borrelia spp. related to relapsing-fever spirochetes were detected in Ireland for the first time. The results of the present study contribute to the validation of blood-meal analysis as a means of determining the host origin of certain pathogens in unfed questing ticks, and raise some questions concerning the extent of B. burgdorferi s.l. host specificity.
Pichon
Bruno
B
Department of Environmental Resource Management, University College Dublin, Belfield, Dublin, Ireland.
Rogers
Mark
M
Egan
Damian
D
Gray
Jeremy
J
D000818:Animals; D001096:Arachnid Vectors / Q000382:microbiology*; D001483:Base Sequence; D001898:Borrelia / Q000302:isolation & purification*; D025065:Borrelia burgdorferi / Q000302:isolation & purification; D015748:Borrelia burgdorferi Group / Q000302:isolation & purification; D004197:Disease Reservoirs / Q000662:veterinary*; D004784:Environmental Monitoring; D046094:Galliformes / Q000097:blood / Q000235:genetics; D006790:Host-Parasite Interactions; D007494:Ireland; D008969:Molecular Sequence Data; D009758:Nymph / Q000382:microbiology; D016133:Polymerase Chain Reaction; D015995:Prevalence; D012377:Rodentia / Q000097:blood / Q000235:genetics; D012418:Ruminants / Q000097:blood / Q000235:genetics; D012621:Seasons; D020308:Songbirds / Q000097:blood / Q000235:genetics; D013045:Species Specificity; D013987:Ticks / Q000382:microbiology*