Community Sustains Control of Disease-Causing TicksBy Rosalie Marion Bliss
March 23, 2009
Spring is finally here, and with it comes tick season. Agricultural Research Service (ARS) scientists are reporting the latest in a series of related studies on the effectiveness of an ARS technology that reduces tick populations.
The blacklegged tick, Ixodes scapularis, in its nymphal stage, is the main vector of the pathogen that causes Lyme disease. The lone star tick, Amblyomma americanum, is a vector of the pathogen that causes human monocytic ehrlichiosis. Both diseases are serious human health problems in large areas of the United States, including Maryland.
A patented and environmentally friendly device called the "4-Poster" Deer Treatment Bait Station was developed by ARS researchers at the Knipling-Bushland U.S. Livestock Insects Research Laboratory in Kerrville, Texas, including J. Mathews Pound and J. Allen Miller.
As part of the USDA Northeast Areawide Tick Control Project, ARS entomologist John F. Carroll with the Animal Parasitic Diseases Laboratory in Beltsville, Md., led a study in which the 4-Poster technology was applied to reduce populations of these deer-associated ticks.
Tick counts on Gibson Island, Md., showed that the treatment annually achieved at least 77 percent control of both tick species, compared to pretreatment years. Gibson Island is a private, resident-owned community that purchased 15 4-Poster devices and operated them during the last five years of the 9-year study. Significant control continued in spite of increased deer density and the use of 40 percent fewer 4-Poster devices after the first four years of the study.
The device consists of four paint rollers that have been impregnated with acaricide, or tick killer. The vertically placed paint rollers flank each corner of a bin containing corn bait. The animal picks up a small but sufficient amount of acaricide that kills ticks when its head, neck and ears rub against the rollers.
The study showed that a community-operated 4-Poster program, when used according to guidelines, can effectively keep tick populations at low levels, according to the researchers.
The study will appear in an upcoming issue of the journal Vector-Borne and Zoonotic Diseases.
ARS is the principal intramural scientific research agency of the U.S. Department of Agriculture.