|STAFFORD III, KIRBY - Connecticut Agricultural Experiment Station|
|DENICOLA, ANTHONY - White Buffalo, Inc|
|MILLER, J. - Retired ARS Employee|
|GEORGE, JOHN - Retired ARS Employee|
Submitted to: Vector-Borne and Zoonotic Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/9/2009
Publication Date: 8/1/2009
Citation: Stafford Iii, K.C., Denicola, A.J., Pound, J.M., Miller, J.A., George, J.E. 2009. Topical Treatment of White-Tailed Deer with an Acaricide for the Control of Ixodes Scapularis (Acari: Ixodidae) in a Connecticut Lyme Borreliosis Hyperendemic Community. Vector-Borne and Zoonotic Diseases.9:371-379.
Interpretive Summary: The ARS-patented 4-Poster Deer Treatment Bait Station for the topical treatment of white-tailed deer, against blacklegged ticks using the acaricide amitraz, was evaluated in a Lyme borreliosis endemic community in Connecticut. The 4-Posters were active October to mid-December and March into May that corresponded to the peak periods of activity for adult ticks in this particular area. Usage of 4-Posters by deer generally was greater than 90%, except during periods of high acorn crops in the falls of 1998 and 2001. From 1999 through 2003, there were 46.1%, 49.6%, 63.4%, 64.6%, and 70.2% reductions in host-seeking, nymphal ticks in treatment areas, respectively, when compared with tick populations in the untreated community. The passive topical application to deer of the acaricide amitraz resulted in a significant decrease in the population of free-living, blacklegged tick nymphs in the treatment area in Connecticut.
Technical Abstract: The 4-Poster device for the topical treatment of white-tailed deer, Odocoileus virginianus (Zimmermann), against ticks using the acaricide amitraz, was evaluated in a Lyme borreliosis endemic community in Connecticut. As part of a 5-year project from 1997 to 2002, 21–24 of the 4-Posters were distributed at residential sites in Old Lyme, CT, in a core treatment area of ˜5.2km2 in fall 1997. The 4-Posters were active October to mid-December and March into May, corresponding to the peak periods of activity for adult Ixodes scapularis in this particular area. Corn consumption ranged from 361 to 4789 kg/month for October and November and 696–3130 kg/month during April. Usage of 4-Posters by deer generally was high (>90%), except during acorn masts in fall 1998 and 2001. Amitraz was applied by rollers at the estimated rate of 1.3 g active ingredient/ha/year. The abundance of host-seeking, I. scapularis nymphs declined significantly ( p<0.001) in the core treatment area, as compared to a control community in Old Saybrook, CT, through 2004, over the project period from 1998 to 2003, from 9.3/100m2 to 0.97/100m2, rising to 1.90/100m2 in 2004. From 1999 through 2003, there were 46.1%, 49.6%, 63.4%, 64.6%, and 70.2% reductions, respectively, in the nymphal tick population in comparison with the untreated community and initial tick abundance in 1998. Control of I. scapularis adults declined to only 19.1% in 2004; 2 years after the treatment of deer was discontinued. Differences in nymphal tick abundance between the control and core treatment area were significant in 1999 ( p=0.042) and highly significant in 2001 ( p<0.001) and 2002 ( p=0.002). The passive topical application to deer of the acaricide amitraz resulted in a significant decrease in the population of free-living, I. scapularis nymphs in the treated core in Connecticut.