Efficacy of an amitraz-impregnated collar in preventing transmission of Borrelia burgdorferi by adult Ixodes scapularis to dogs.
OBJECTIVE
To determine whether an amitraz-impregnated collar could prevent transmission of Borrelia burgdorferi by Ixodes scapularis to dogs.


METHODS
Laboratory trial.


METHODS
8 specific-pathogen-free Beagles.


METHODS
On days -15 and -1, all dogs had negative ELISA results for serum antibodies against B. burgdorferi. On day 0, 4 dogs were each fitted with an amitraz-impregnated (9%) collar, and 4 dogs served as untreated controls. On day 7, all dogs were infested with 100/scapularis (approx 50 females and 50 males) with a known B. burgdorferi infectivity rate of 39.4%. On days 21, 28, 35, 42, 56, 70, and 84, each dog was tested for serum antibodies against B. burgdorferi via ELISA and a western blot technique. Additional ELISA were also performed for serum antibodies against antigenically similar organisms.


RESULTS
By day 70, all control dogs had developed serum ELISA responses ranging from 328 to 510 kinetics-ELISA units (equivalent to end-point titers of approx 43,500 to 60,000), whereas treated dogs remained seronegative throughout the study. Western blot assays performed on all serum samples confirmed that antibodies detected in control dogs reflected responses to specific antigens of B. burgdorferi, whereas treated dogs had no such antibodies. Additional serologic analyses confirmed that antibody responses observed in control dogs were not attributable to antigenically similar organisms.


CONCLUSIONS
Amitraz-impregnated collars prevented transmission of B. burgdorferi in 4 of 4 treated dogs and may be a useful management tool for prevention of borreliosis in dogs.
Elfassy
O J
OJ
Virbac AH Inc, Fort Worth, TX 76137, USA.
Goodman
F W
FW
Levy
S A
SA
Carter
L L
LL
D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D001096:Arachnid Vectors / Q000382:microbiology; D015748:Borrelia burgdorferi Group / Q000276:immunology / Q000502:physiology; D004283:Dog Diseases / Q000188:drug therapy / Q000517:prevention & control*; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D007302:Insect Repellents / Q000008:administration & dosage* / Q000627:therapeutic use; D018884:Ixodes / Q000382:microbiology*; D008193:Lyme Disease / Q000517:prevention & control / Q000662:veterinary*; D008297:Male; D011897:Random Allocation; D013047:Specific Pathogen-Free Organisms; D013984:Tick Infestations / Q000517:prevention & control*; D014052:Toluidines / Q000008:administration & dosage* / Q000627:therapeutic use
D000907:Antibodies, Bacterial; D007302:Insect Repellents; D014052:Toluidines; C014983:amitraz