[APWG] More on New Device Available for Control of Ticks Over LargeAreas

[Marc Imlay]

Apologies for the long message. Lyme disease is the primary safety
concern of invasive plant control folks. I emphasize all my volunteers
take a bath that day and check for ticks. I know at least a dozen
people who caught lyme disease. Of these 3/4 were cured completely
but one out of four were not. Amazingly, all of them have come back
to enjoy the woods on a regular basis. Experiencing Nature is, of
course, a fundamental part of human nature and Lyme disease should
be controlled.  One can also argue that an alien invasive bacteria and
its control belongs on list serves for plants just as much as SOD, a
fungus which is technically not a plant.

Anyway you and I and other leaders in invasive plant control have an
obligation to cover Borrelia burgdorferi. Thanks.

Marc


Marc Imlay,
Board member of the Mid-Atlantic Exotic Pest Plant Council,
Hui o Laka at Kokee State Park, Hawaii
Vice president of the Maryland Native Plant Society,
Chair of the Biodiversity and Habitat Stewardship Committee for the
Maryland Chapter of the Sierra Club.




www.csrl.ars.usda.gov/kbuslirl/n-east.htm provides more
information on the "New Device Available for Control of Ticks
Over Large Areas". Below is the written portion (without pictures
and graphs) Most comments I have received concern the relationship
with hunting and impact on the size of the deer population. As examples:

What is the effectiveness in areas with an annual deer hunt compared
to areas without an annual hunt? Will it increase deer population
without control by hunting? What is the effectiveness where hunting
keeps the deer population down to a natural level that predators used
to do (10-20 per square mile)?

In this regard http://www.caes.state.ct.us/Frontiers/V51-60/V53N2.pdf
indicates that alien invasive Borrelia burgdorferi retains its proportion in
reduced populations of deer (40 per square mile) and deer ticks.

Marc Imlay,
Board member of the Mid-Atlantic Exotic Pest Plant Council,
Hui o Laka at Kokee State Park, Hawaii
Vice president of the Maryland Native Plant Society,
Chair of the Biodiversity and Habitat Stewardship Committee for the
Maryland Chapter of the Sierra Club.


USDA Northeast Area-wide Tick Control Project
"A Community-based Field Trial of ARS-patented
Tick Control Technology Designed to Reduce the Risk
of Lyme Disease in Northeastern States"
An Area-wide Cooperative Demonstration Project Between USDA-ARS and
a Consortium of Universities and State Agencies to be Conducted in
Connecticut,
Maryland, New Jersey, New York, and Rhode Island



CONTENTS
I. Principal Investigators
II. Executive Summary
III. Problem Statement and Justification for the Need of an Area-Wide
Management Approach
A. The Problem
B. The Need for Community-based Approaches to Control Ixodes scapularis on
White-tailed Deer
C. Technology Development
D. Potential for reducing Lyme disease risk
IV. Objective and Experimental Design
A. Specific Objective
B. Plan of Work
C. Assessment - Estimating Efficacy
D. Technology Transfer
E. Program Management
V. Anticipated Program Benefits
VI. Facilities and Equipment



I. Principal Investigators:
John E. George, Ph.D. (830-792-0339), J. Mathews Pound, Ph.D.
(830-792-0342), and J. Allen Miller, Ph.D. (830-792-0321) USDA, ARS,
Knipling-Bushland U.S. Livestock Insects Research Laboratory, 2700
Fredericksburg Rd, Kerrville, TX 78028-9184
Durland Fish, Ph.D.(203-785-3525), Yale School of Medicine, Department of
Epidemiology and Public Health, 60 College St., P.O. Box 208034, New Haven,
CT 06510-8034
Gary A. Mount, Ph.D. (Retired, Collaborator) (352-374-5900) - USDA, ARS,
Center for Medical, Agriculture, and Veterinary Entomology, PO Box 14565,
1600 SW 23rd Dr., Gainesville, FL 32608
Kirby Stafford III, Ph.D.(203-789-7242), Connecticut Agricultural Experiment
Station, 123 Huntington St., P.O. Box 1106, New Haven, CT
John F. Carroll, Ph.D. (301-504-9017), USDA, ARS, Livestock and Poultry
Sciences Institute, BARC-EAST Bldg. 177C, Beltsville, MD 20705
Terry L. Schulze, Ph.D. (908-446-2243), Contractor, 9 Evergreen Court,
Perrineville, NJ 08535
Thomas J. Daniels, Ph.D. (914-273-3078), Fordham University, Louis Calder
Ecology Center, 53 Whippoorwill Road, Armonk, NY 10504
Thomas N. Mather, Ph.D. (401-874-2791), Department of Plant Sciences,
University of Rhode Island, 240 Woodward Hall, Kingston, RI 02881-0804

II. Executive Summary
Lyme disease is the most prevalent vector-borne human disease in the United
States. More than 100,000 cases have been reported to the National centers
for Disease Control and 90% of these cases occur in the Northeastern states,
between Massachusetts and Maryland. Lyme disease is caused by infection with
the spirochete Borrelia burgdorferi, which is transmitted in the Northeast
by the blacklegged tick, Ixodes scapularis. Several published field studies
conducted in the Northeast indicate that I. scapularis populations cannot be
maintained in the absence of white-tailed deer. While immature stages of I.
scapularis feed upon a wide variety of vertebrate hosts, it is estimated
that 95% of the female population feeds on deer. Exploitation of the
dependent relationship of I. scapularis reproduction on white-tailed deer by
preventing ticks from feeding on deer should result in a dramatic reduction
in tick density for all stages and, consequently, an equally dramatic
reduction in Lyme disease risk for humans.

A passive topical treatment system termed the '4-poster' was invented by ARS
to provide a means for controlling I. scapularis on deer. The majority
(83-89%) of female I. scapularis attach to the head, neck, shoulders, and
brisket. The device is designed to take advantage of this distribution of
ticks on deer through contact between these areas and vertical pesticide
application rollers that apply the acaricide amitraz while deer feed on corn
in receptacles at both ends of the '4-poster'. Through grooming, acaricide
is transferred to other body areas, such as the brisket, axillae, groin, and
vent, providing additional coverage.

Simultaneous trials have been organized for sites in hyperendemic
communities of Connecticut, Maryland, New Jersey, New York, and Rhode Island
to determine if the '4-poster' is an effective tool for controlling I.
scapularis and reducing the risk of Lyme disease. Each of the sites differ
in terms of ecological conditions and community structure. Three study sites
(CT, NY, and RI) are residential with high peridomestic exposure and
free-ranging deer herds. The fourth site (NJ) is a fenced military base with
peridomestic exposure risk and a confined deer herd. The fifth site (MD) is
currently being determined.

Efficacy of the treatments will be based on comparisons of differences in
the density of ticks in sites where self-treatment of deer with '4-posters'
has occurred versus untreated control sites. Bites from infected nymphal
ticks are the most common mode of transmission to humans for the Lyme
disease agent; therefore, a reduction in the density of this life stage will
be the major basis of assessing impact. The goal of the project is to reduce
the number of infected nymphal I. scapularis in the treated areas by at
least 90% by the end of the fourth year of the proposed five-year project.
The fifth year the emphasis will be to transfer the technology to interested
parties for practical application.

The project will be coordinated by a team including ARS scientists and an
authority on Lyme disease who is at the Yale University School of Medicine.
Location Coordinators who are recognized experts on the biology and control
of I. scapularis will perform independent trials in each of the five
locations, but all will follow a mutually developed protocol with free
exchange of information.

It is anticipated that a successful execution of this project will result in
the first practical solution to the problem of tick-borne diseases in the
Northeast and in other affected regions of the country.
III. Problem Statement and Justification for the Need of an Area-wide
Management Approach

A. The Problem
Lyme disease is the most prevalent vector-borne human disease in the United
States. Since 1982, when Lyme disease first became a reportable disease,
more than 100,000 cases have been reported to the Centers for Disease
Control and Prevention (CDC 1996, 1997). The actual number of cases is
estimated to be at least three times that officially reported (Campbell et
al. 1997). Although cases have been reported from 48 states, more than 90%
of Lyme disease cases occur in the Northeastern states, between
Massachusetts and Maryland. Seven hyperendemic counties in coastal
Connecticut and Southern New York State account for nearly 50% of the total
cases. In 1996, the number of cases reported to the CDC increased by 41%
over the previous year. This increase was due to increases in both the
geographic distribution and population density of the tick vector in the
Northeastern states (CDC 1997). Further increases can be expected as
populations of I. scapularis continue to increase and spread into new areas
of the Northeast where human density is highest (Lastivica et al. 1989,
White et al. 1991, Daniels et al. 1993).



The causative agent of Lyme disease, Borrelia burgdorferi, is transmitted by
the blacklegged tick Ixodes scapularis. It is in the highly endemic areas in
the Northeast and upper Midwest where a combination of factors including
tick density, abundance of vertebrate host species, and local landscape
features are related to a very high degree of risk of Lyme disease in humans
(Barbour and Fish 1993). The recent emergence of Lyme disease as the major
vector-borne human disease in the United States can be traced to ecological
changes in the Northeastern and Midwestern states (Spielman et al. 1985,
Matuschka and Spielman 1986) and a rebound of white-tailed deer populations
from near extinction at the end of the nineteenth century to the high
population densities of the species that occur throughout much of their
range today. Because there is a positive correlation in space and time
between the density of deer populations and the abundance of I. scapularis
(Spielman et al. 1985), the white-tailed deer has been described as a
"keystone" host (Barbour and Fish 1993) of I. scapularis populations.
Field studies conducted in the Northeast indicate that I. scapularis
populations cannot be maintained in the absence of white-tailed deer (Wilson
et al. 1985, Daniels et al. 1993, Stafford 1993). Although various
medium-sized mammals such as raccoons, opossums, cats, and dogs are
parasitized by adult ticks (Fish and Dowler 1989), over 95% of female I.
scapularis are estimated to feed on deer (Wilson et al. 1990). Schmidtmann
and Carroll (1997) observed that 89% of the females and 88% of the male I.
scapularis feeding on deer were attached to the outside of the ears, head,
neck and brisket. Watson and Anderson (1976) reported that 82.5% of adult
ticks were attached to the head, neck, or shoulders. Effective exploitation
of the dependent relationship of I. scapularis upon white-tailed deer by
preventing adult ticks from feeding on deer should result in a dramatic
reduction in tick density for all stages and, consequently, a reduction in
Lyme disease risk.

B. The Need for Community-based Approaches to Control Ixodes scapularis on
White-tailed Deer.

The high incidence of Lyme disease in the Northeast is caused by intense
peridomestic exposure of suburban and rural residents to infectious tick
bites by I. scapularis (Falco et al. 1988, Fish 1995). The density of I.
scapularis is highest within the mosaic landscape of deciduous forests and
suburban residential properties that characterizes Lyme disease endemic
communities in this region (Maupin et al. 1991, Frank et al. 1997). The use
of personal protection measures (repellents and protective clothing), is
both inappropriate and ineffective against the constant exposure of tick
bites experienced by residents living in hyperendemic communities. Although
progress in developing an effective human vaccine against Lyme disease has
been encouraging (Barbour and Fish 1993), no vaccine is currently available.
Also, the emergence of other I. scapularis-borne human pathogens in the
Northeast, such as human granulocytic ehrlichiosis, babesiosis, and
tick-borne encephalitis virus (CDC 1995, Telford et al. 1997) precludes
complete disease prevention from I. scapularis-borne pathogens by Lyme
disease vaccines alone.

A substantial body of literature reports research on tests of a variety of
methods used to control I. scapularis and reduce the risk of tick-borne
disease in the Northeast. However, various problems such as adverse
environmental impacts, risks of insecticide exposure to humans and pets,
high cost, and inconsistent efficacy, have limited their impact upon the
incidence of Lyme disease. Management technologies that have been explored
to control I. scapularis include habitat modification, area-wide acaricide
applications, acaricide self-treatment of the rodent reservoir of B.
burgdorferi, white-tailed deer density reduction, and deer exclusion by
fencing.

Attempts to control I. scapularis by habitat management techniques have been
limited to burning (Mather et al. 1993) and leaf litter removal (Schulze
1995). These techniques have met with some success, and further research on
landscape modification as a method to reduce tick abundance is in progress.
However, large-scale changes, such as tree thinning, vegetation removal and
burning are incompatible with the privately owned and managed residential
properties characteristic of many hyperendemic communities.
Area application of acaricides has been shown to effectively reduce the
density of I. scapularis when applied either aerially (Schulze et al. 1992)
or by ground-based applicators (Allan and Patrican, 1995; Schulze 1987,
1991, 1994; Solberg et al. 1992; Schulze and Jordan 1995). However, large
scale control with acaricides cannot be implemented in many areas because of
environmental concerns. Individual premises treatment of high-risk
properties in hyperendemic communities with acaricides is also effective in
reducing I. scapularis populations (Curran et al. 1993, Stafford 1991a).
However, efficacy of such applications are usually temporary and
stage-specific, requiring repeated treatments both seasonally and annually
for full protection from tick bites.

Acaricide self-treatment of Peromyscus leucopus, the rodent reservoir of B.
burgdorferi has been evaluated in several regions of the Northeast, but
results have been inconsistent (Mather et al. 1987, 1988; Daniels et al.
1991; Deblinger and Rimmer 1991; Stafford 1991b, 1992). Differing ecology
and host-species composition within the range of hyperendemic communities in
the Northeast precluded wide acceptance of this technique.

Reducing the abundance of white-tailed deer in affected communities has been
attempted (Wilson et al. 1985, 1988; Deblinger et al. 1993), but near total
elimination of deer is required to reduce the risk of Lyme disease
significantly. State wildlife regulations and public opinion preclude deer
reduction as method for impacting I. scapularis populations and Lyme disease
risk. Elimination of deer can be achieved in small areas by fencing. The
effect of excluding deer from residential properties with deer-proof fencing
has been evaluated in hyperendemic areas of New York and Connecticut and was
found to be highly effective in reducing Lyme disease risk (Daniels et al.
1993, Stafford 1993). However, the high cost of purchase and maintenance of
ten- foot fencing to exclude deer from individual residences has prevented
large-scale implementation for Lyme disease prevention.

An acaricide treatment directly delivered to deer which will prevent feeding
of adult stage ticks (Miller et al. 1989; Pound et al. 1994, 1996;
Sonenshine et al. 1996) appears to be a strategy with great potential for
having wide-scale impact upon Lyme disease risk. Effective treatment would
result in the equivalent of eliminating deer as hosts for adult I.
scapularis, resulting in the loss of reproductive ability for the population
and elimination of all stages within the two to three years encompassing the
natural life span of one generation.

Mount et al. (1997) developed a computer model which simulates I. scapularis
populations and Lyme disease risk. This model has been used to simulate the
effects of all tick control technologies available for I. scapularis,
employed individually or in combination. These simulations were run with
data for normal weather patterns and population densities specific for
coastal Connecticut and New York. Results show that area-wide acaricide
applications, vegetative reduction, or a combination of these technologies
would be useful for short-term seasonal management of ticks and Lyme disease
risk in small recreational or residential sites. Simulations of
self-treatment of mice did not have a significant impact, as confirmed by
published field trials. Deer density reduction showed that this approach
might be considered as a management strategy component if such an approach
were possible. However, of all the control technologies simulated, acaricide
self-treatment of deer was the most efficacious technology for reducing the
abundance of I. scapularis in long-term management programs over large
areas. Simulations revealed that this approach would be more effective than
deer removal alone.

C. Technology Development
Agricultural Research Service entomologists at the Knipling-Bushland U.S.
Livestock Insects Research Laboratory in Kerrville, TX have focused research
on tick control on methods for deer self-treatment. To date they have
developed and tested two self-treatment approaches for the control of ticks
on white-tailed deer. One of the technologies is whole kernel corn medicated
with ivermectin and fed systematically to deer (Miller et al. 1989, Pound et
al. 1996). Because of limitations of the medicated bait approach for
controlling I. scapularis, a passive topical treatment system called the
'4-poster' was developed and patented as an alternative (Pound et al. 1994).
The device is designed to selectively apply an acaricide, such as amitraz,
directly to the heads, ears, and necks of deer through contact with vertical
applicator rollers while they feed on corn dispensed from a central storage
bin. Through grooming, acaricide is transferred to other body areas such as
the brisket, axillae, groin, and vent. Amitraz is highly toxic to ticks, but
it has low mammalian toxicity, consequently, there are no restrictions
associated with residue in treated animals. Deer may be consumed the day of
treatment.

A trial to evaluate the effectiveness of the '4-poster' device for the
control of the lone star tick on wild white-tailed deer held within ca. 50
acre deer-fenced pastures is in its second year at the Kerr Wildlife
Management Area, Hunt, TX. During February through August each year, a
single '4-poster' device is placed in each of two pastures having comparable
numbers of lone star ticks and white-tailed deer. Point-Guard®, a 2% active
ingredient pour-on formulation of the formamidine acaricide amitraz, is the
acaricide being used on the applicator rollers of the '4-poster' in the
Treatment Pasture. No acaricide is being used with the device in the Control
Pasture. During the 1996 treatment period the first year, seven deer were
darted in each pasture and whole body counts of ticks were made. Comparisons
of tick numbers from anesthetized animals in the Treatment vs. Control
Pastures showed 97.5, 95.4 and 99% control of adults, nymphs, and larvae,
respectively, on the deer examined in the Treatment Pasture. Not only were
the ears, heads, and necks free of ticks, but ticks were also absent from
the briskets, axillae, and vents where some adult lone star ticks usually
attach. Apparently, acaricide is transferred to these areas when deer groom.
Estimates of the percentage control of free-living ticks, based on samples
of adult and nymphal lone star ticks collected from Treatment and Control
Pastures during June of the second year (1997) of the trial, were 85 and 92,
respectively. Larvae will be sampled later in the summer when this life
stage is active. These results are comparable to the degree of control
obtained with ivermectin medicated bait (Pound et al. 1996).

A trial with '4-posters' and 10% permethrin as the acaricide is underway in
Maryland at Goddard Space Flight Center where treated deer are confined by a
game fence and untreated deer are in an area of the Patuxent National
Wildlife Refuge. Detailed results are not available, but Solberg (pers.
comm.) reports that deer readily consume corn from the '4-posters' and a
substantial reduction in the numbers of I. scapularis in the treatment area
has occurred. Daniels et al. (pers. comm.) in Westchester Co, NY, and
DeNicola and Stafford (pers. comm.) in Bridgeport, CT, report that
white-tailed deer are attracted to the corn in '4-posters' and readily
consume it. These experiences with '4-posters' at Northeast and Mid-Atlantic
locations show that deer visit the devices and consume corn from them in a
manner similar to that observed in central Texas.

D. Potential for reducing Lyme disease risk.
Development of the '4-poster' technology for controlling lone star ticks
provides a unique opportunity to impact human disease risk due to tick-borne
pathogens. Lyme disease is the most prevalent tick-borne pathogen affecting
public health in the U.S. The blacklegged tick vector of Lyme disease and
the lone star tick are equally dependent upon deer to maintain population in
natural environments. Accordingly, the '4-poster' technology developed by
the USDA Kerrville laboratory should have equally dramatic impact upon
populations of I. scapularis in the Northeast where Lyme disease is endemic.
In September 1996, a meeting was held with ARS representatives from
Beltsville, Kerrville, and Gainesville laboratories, ARS National Program
Staff, representatives of the military, and Lyme disease expert Dr. Durland
Fish from Yale School of Medicine to discuss the potential of the '4-poster'
technology for reducing the risk of Lyme disease. From discussions of Lyme
disease epidemiology, computer simulations of I. scapularis populations, and
the success of the '4-poster' device in controlling lone star ticks in
Texas, it became apparent that this technology has enormous and immediate
potential for impacting Lyme disease in the Northeast.

In November 1996, meetings were convened in Armonk, NY, New Haven, CT, and
Kingston, RI to visit with state and local public health, wildlife, and
environmental agencies, the public, and scientists to solicit reactions to
community-centered trials using the '4-poster' technology. We asked for
input on need, public acceptability, regulatory issues, and practicality.
The consensus at all locations was enthusiasm about the possibility of the
device becoming available for community tick control projects. The only
regulatory condition we could not meet at the time was the need to have an
Experimental Use Permit (EUP) for Point-Guard® granted by the Environmental
Protection Agency (EPA). On June 20, 1997 our application for an EUP to use
the Point-Guard® formulation of amitraz in the '4-posters' to treat
white-tailed deer was issued, and it is effective for five years beginning
on the first date of use. The EUP covers the use of Point-Guard® in the
states of Connecticut, New Jersey, New York, and Rhode Island. An additional
application will be submitted to add Maryland.

Simultaneous trials have been organized for sites in CT, NJ, NY and RI where
Lyme disease is hyperendemic. Each of the sites differ in terms of
ecological conditions and community structure. Three study sites,(CT, NY and
RI) are residential communities with high peridomestic exposure risk and
free-ranging deer herds. The fourth site (NJ) is a fenced military base with
peridomestic exposure risk and a confined deer herd. The sites were selected
because they are foci of Lyme disease and other I. scapularis- transmitted
pathogens, and they are sufficiently different to provide a range of
circumstances in which to test the device. Also, entomologists and wildlife
biologists with international reputations have studied these areas and have
joined with us to form a research consortium. The members of the consortium
developed the final experimental design, including a uniform method for
assessing efficacy at each location. Recently, a decision was made to add
Maryland to the consortium subject to location of an appropriate site,
approval from EPA of an EUP for the location, and approval of state
officials. Details of project management are provided in the third section
of this proposal.

IV. Objective and Experimental Design

A. Specific Objective
The purpose of this initiative is to determine the efficacy of Point-Guard®
(2% amitraz) applied to white-tailed deer using the USDA-ARS patented
'4-poster' treatment device in reducing the risk of Lyme disease in endemic
communities of the Northeast. Controlling adult I. scapularis on deer will
reduce numbers of free-living ticks which transmit the causative agent B.
burgdorferi and other tick-borne pathogens to humans. Populations of the
lone star tick, Amblyomma americanum, will be similarly affected where they
occur, which will further reduce the risk of tick-borne disease.

B. Plan of Work
The '4-poster' Device and the Acaricide
The '4-poster' device has a central bin that is the reservoir for the whole
kernel corn that is the bait to attract deer to the two feeding/application
stations located on each end. These stations each have a single feeding port
adjacent to two vertical applicator rollers. A horizontal plate partly
obscures each feeding port and forces deer to rub their ears, heads, and
necks against the rollers as they feed. The vertically positioned rollers
permit treatment of both antlered and antlerless deer, and allows
unobstructed retraction of the head upwards if deer are startled while
feeding. This design also facilitates use by multiple deer and minimizes
chances of the deer being injured or the rollers being damaged.
Buck using the patented, USDA-ARS '4-poster' device for control of ticks on
white-tailed deer.




Typical field infestation of lone star ticks on white-tailed doe during
spring and summer seasons.




White-tailed doe allowed access to the '4-poster' for control of ticks.

The acaricide product chosen for use in the devices is a 2% pour-on
formulation of amitraz, marketed as Point-Guard® (Hoechst Roussel Vet,
Somerville, NJ). In a trial to obtain an estimate of the amount of
Point-Guard® that deer could be expected to remove daily from the applicator
rollers, a '4-poster' fitted with an internal acaricide reservoir and an
on-demand deer-activated dispensing system was placed in a pasture with nine
deer that had 24-hour access to the device. Over the period of treatment,
usage by the deer resulted in the dispensing of approximately 14.3 ml of
product per day to the upper surfaces of the rollers, or approximately 100
ml per week. This is equivalent to usage rates of roughly 3.6 ml per roller
per day, or 1.6 ml per deer per day. In '4-poster' devices to be used in the
Northeast Area-wide Tick Control Project, the reservoir and automatic
dispensing system has been replaced by a manual dosing approach that greatly
reduces potential hazards to humans, wildlife and the environment,
appreciably reduces the cost of constructing the devices, minimizes
maintenance efforts by operators, and maximizes control of the amount of
pesticide applied to the rollers. Point-Guard® will be applied manually to
individual rollers at a similar rate of approximately 20 ml per roller per
week using the calibrated dosing guns sold by Hoechst Roussel Vet. These
guns will be retrofitted with hooded adapters designed by ARS to
specifically facilitate injection of the product into the upper surface of
the rollers.

Project Locations
The five sites at which trials will occur differ in terms of factors such as
physical environment, structure of plant communities, diversity and density
of vertebrate species, and landscape of the properties on which homes are
located. At two of the sites, MD and NJ, most of the area will be natural
forest with few homes. The sites are as follows: 1) around the town of Old
Lyme, New London County, Connecticut; 2) Naval Weapons Station Earle, an
active military base in Monmouth County, New Jersey; 3) in and around the
town of Bedford, Westchester County, New York; and 4) in and around the town
of Narragansett, Rhode Island. The site in Maryland has not yet been
selected.

Treatment Strategies
Site Selection Criteria -The primary strategy is to assess the effectiveness
of the '4-poster' technology in reducing populations of free-living nymphs
within a "Core Treatment Area" that is centrally located within a "Treatment
Site" and to evaluate results by comparison of tick populations in the Core
Treatment Area to those in a similar but separate "Control Site". Core
Treatment Areas will be approximately 518 hectares (=1280 acres or 2 mi²)
each, and efforts will be concentrated on controlling ticks within these
areas. The '4-poster' devices will be deployed only within a Core Treatment
Area. Both Treatment and Control Sites will be selected that are more
circular than elongate. Control Sites will be similar in size to Core
Treatment Areas. Because acaricide is being applied to free-ranging deer,
the precise region in which tick control occurs will depend on movement and
daily activity of deer that use the devices. Therefore a Treatment Site will
be selected that is large enough to contain both the 518 hectare Core
Treatment Area and enough peripheral area that a gradient of control outward
from the Core Treatment Area can be demonstrated.

The relative sizes of the Treatment Sites will be variable among locations
to accommodate the individual characteristics of the regions surrounding the
Core Treatment Areas and to demonstrate the decreasing gradient of efficacy
at the outer margins of the Core Treatment Areas. Control Sites will be
selected that either will be a minimum of 3.2 kilometers (=2 miles) from the
outer margins of the Core Treatment Sites or they will be separated from the
Core Treatment Sites by a physical barrier such as an impenetrable
deer-fence or a freeway to assure no cross-over effects from treated deer
entering the untreated Control Sites. The objective is to evaluate efficacy
of treatment with the '4-poster' device vs. no treatment. Control Sites will
be selected that will not be treated for ticks by homeowners, professional
pest control operators or others during the period of the study. So that
Control Sites will remain representative of 'natural' populations of ticks,
no '4-poster' devices will be supplied by researchers at these sites.
Supplemental feeding of deer would artificially increase tick densities in
Control Sites.

Schedule for the Project -To allow deer to acclimate to the devices and
begin using them on a regular basis, the '4-poster' devices with corn but
without acaricide will be placed in the field on or around 15 August in
Connecticut, New York, and Rhode Island, and 1 September in Maryland and New
Jersey. During the first 30 days thereafter, placement of the devices will
be adjusted to optimize usage by deer. Optimization will be based on several
factors including the rate of consumption of corn, direct observation of
deer and other animals near the devices, the amount of hair and degree of
soiling of the rollers (an indication of usage), and spatial analysis of
corn consumption data for individual devices.

Although treatment dates are subject to change as a result of unusual or
extreme weather patterns, yearly applications of Point-Guard® to deer will
occur from 15 September to 15 December then begin again on 15 March and end
on 15 May in Connecticut, New York, and Rhode Island for a total of 151
treatment days. Applications in Maryland and New Jersey will be from 1
September through 15 December and resume on March 15 and continue though
August 31 for a total of 244 treatment days and will include late Spring and
Summer months when lone star ticks feed on white-tailed deer. Treatments at
any individual location, however, may be temporarily suspended during
periods of tick inactivity that occur when air temperature remains below
7.2° C ( 45° F) for extended periods or when snow cover exceeds 2.5 cm. Life
cycles of ticks in the Northeast may be quite long, with the blacklegged
ticks requiring two or perhaps three years to develop from eggs to adults,
and lone star ticks perhaps requiring two years.

Having recently joined The Northeast Area-wide Tick Control Project,
researchers in Maryland have not yet selected Treatment nor Control Sites,
because none are yet available for which adequate pretreatment tick
population indexes and deer density values are known. Therefore, initial
deployment of the '4-poster' devices and acaricide treatment of deer in
Maryland will be delayed for one year to select study sites and to permit
collection of appropriate pretreatment tick and deer baseline population
data.

A minimum of four years of treatment is planned in order to demonstrate the
maximal degree of efficacy on free-living tick populations. Considering that
this technology has never before been tried under unrestricted field
conditions, it is possible that unforeseen problems may arise that could
lead to an ineffective first year of treatment. Activities the fifth year
will be final assessment of efficacy and technology transfer.
Distribution and Management of '4-poster' Devices - The '4-poster' devices
will be deployed at a rate of 25 devices per Core Treatment Area
(approximately 1 device for each 20.7 hectares or 51.2 acres), and they will
be strategically placed in attempts to treat every deer that enters, leaves,
or otherwise exists within a Core Treatment Area. Placement of the devices
will be at the discretion of individual researchers and should be dependent
upon the activities and movements of the deer. Therefore it is not necessary
or even advisable to place them in a precise grid-like pattern. Researchers
will contact property owners in desired locations and obtain permission to
install devices. It is intended that devices be installed on private
property to minimize vandalism and maximize use by deer.

As devices are installed, they will be individually numbered, then leveled
to assure proper flow of bait from the feeding ports. Precise Global
Positioning System (GPS) coordinates will be obtained for each device, and
they will be filled with twice-cleaned or "recleaned" whole kernel corn of
the type commonly used in automatic deer feeding devices. Initially, corn
will be spread liberally both on the adjustable overhanging plates and on
the ground around the ends of the devices to "chum" the deer into finding
the corn being dispensed from the feeding ports of the devices. After deer
begin using the devices regularly, the "chumming" will be stopped.
Assuming pre-trial maximal estimates of 22 deer per 259 hectares (=1 mi²) or
44 deer per Core Treatment Area in each location, it is anticipated that a
total of approximately 220 deer would be treated during the first year of
the study. Estimates of deer densities at individual locations will be
updated during subsequent years as a result of aerial and other surveying
estimates that will be made during the first year. As mentioned above,
preliminary studies have shown that >97% efficacy in controlling adult ticks
was observed on deer treated with approximately 1.6 ml of the 2% AI
Point-Guard® formulation of amitraz per deer per day. Estimating that 44
deer visit the devices at a single Core Treatment Area daily, a hypothetical
dosage of 70.4 ml of product would be transferred to deer on a single day at
each of the 5 state locations. With 3 locations treating for approximately
151 days and 2 locations for 244 days, all locations combined would require
a total of 941 treatment days yearly, and this multiplied by an estimated
70.4 ml of acaricide transferred to deer per day per location would total
66.25 liters of acaricide per year. Because Point-Guard® is a 2% pour-on
formulation of amitraz equivalent to 0.15 pounds AI per gallon) this
quantity would equate to 1.19 kg AI transferred from the rollers to deer
yearly at the 5 locations combined.

Because the distribution of deer is not homogeneous throughout the Core
Treatment Areas, and a single deer may visit more than one device daily,
acaricide actually will be applied to rollers in amounts considerably
greater than the minimal estimate of 1.6 ml per deer per day. Initially,
each roller will be treated with 25 ml of Point-Guard®. Afterwards,
researchers will evaluate the relative amounts of pesticide on rollers each
week (or more often if needed ) by wiping individual rollers with a brown
paper towel or similar absorbent material to approximate the amount of oily
residue. Then, researchers will add acaricide as necessary, using the
specially adapted applicator guns to apply only amounts in increments of 5
ml similarly to each of the 4 rollers on a single device. Records will be
carefully maintained listing amounts of acaricide applied to each '4-
poster' device. The presence of excessive acaricide will be evident if
residues appear to accumulate on the bottom of a roller or drip into the
spill prevention pan surrounding the bases of the roller/spindle assemblies.
Should over-treatment occur, the roller should be inverted and acaricide
removed from the pan. Researchers will wear protective gloves when contact
with acaricide is possible.

Data Collection
'4-poster' Devices - To maximize use of the devices by deer, it will likely
be necessary to adjust placement of the devices within the Core Treatment
Areas, and these decisions will be based primarily on knowledge or
perception of relative use of the devices. It is important, therefore that
precise data be maintained on the amounts of corn placed in each device and
amounts of pesticide applied to the rollers. Previous studies in Texas have
shown deer to consume roughly 1 pound of whole kernel corn per 100 pounds
body weight per day. Thus, a rough estimate of the use of the device by deer
can be determined from consumption of corn. Graduated marks within the corn
bins of the devices will permit operators to estimate consumption rates of
corn for individual devices. These values and GPS coordinates of individual
devices can quickly be analyzed with spatial analysis software to form a
graphic display of device usage and assist researchers in maximizing device
placement.

White-tailed Deer - Because the behavior and ecology of deer in free-ranging
environments are unknown variables, key measurements of the deer population
and status will be made at each site. Wildlife experts, specifically trained
in deer population ecology, will periodically estimate deer density, the
proportion of deer treated, and the density of ticks on deer.
Deer population estimates will be conducted from December to February when
there is >10 cm of snow cover. A helicopter will be used to fly transects
covering both Treatment and Control Sites. Each transect will be the entire
length of a Site and 150 m in width. Two observers will count all deer on
the transects and record the number and distribution on an aerial
photograph.

Proportions of deer using the devices will be determined by temporarily
replacing acaricide treated rollers with those containing a reflective
marking agent such as microglass beads in a petroleum jelly base that has
been shown to be reflective at night in preliminary trials on deer skin.
This reflective marking agent will allow observations to be made at night
using a spotlight which is easier to accomplish and more accurate than
daylight counts of deer having fluorescent or other colored pigments applied
to them. This technique avoids having conspicuously marked deer in suburban
communities.

Abundance and distribution of ticks on deer will be determined by capturing
12 deer (6 in the Core Treatment Area and 6 in the Control Area) during
October and November. Wildlife biologists having considerable expertise in
handling, restraining, and examining wildlife will capture deer by remotely
immobilizing them with a dart gun from a tree stand near a bait source.
Immobilizing agents will include tiletamine HCl + zolazepam HCl (4.4 mg/kg),
and xylazine HCl (2.2 mg/kg); and yohimbine HCl (0.12 mg/kg) subsequently
will be used to reverse the anesthesia. Anesthetized deer will be inspected
for ticks, and data including counts by stage, sex, state of engorgement,
and location on the host will be recorded. Due to the presence of
anesthetizing drugs within the blood of recently darted deer, darted deer
will be ear-tagged with labeled tags informing persons who might later come
in contact with the animals (i.e. from hunted or road- killed deer) to
notify the appropriate agency and determine if sufficient time has elapsed
between darting and slaughtering before consuming the deer. Ear-tagging will
also be used to prevent the sampling of previously captured deer.
Tick sampling - Because of differences in vegetation types and densities and
other factors, specific methods of tick sampling will vary among locations.
All participating researchers, however, have considerable expertise in
sampling tick populations, and discussions among members of the consortium
have established sampling protocols that will assure collection of
equivalent data sets among locations. Adult, nymphal, and larval population
estimates will be assayed using either standard cloth drag samples, press
boards, or walking samples in which ticks are counted directly on clothing
of the researcher.

To assay efficacy of treatment efforts in Core Treatment Areas, 15 to 20
randomly dispersed plots having vegetation characteristics that are similar
and typical of the type of habitat most likely to harbor ticks within both
Core Treatment Areas and Control Sites will be selected and sampled either
by dragging a total of 100 m², or flagging or walking for 10 periods of 30
seconds in each plot. The 15 to 20 plots will be sampled at as nearly the
same time as possible, and the recorded data set will constitute a single
sample. During anticipated periods of peak activity each year, adults and
larvae will be sampled at least once. Nymphs will be sampled four times
during peak activity because of their paramount importance in Lyme disease
risk.

To assay the extent to which treatment effects extend outward from the
periphery of the Core Treatment Areas, sampling within the Treatment Sites
outward from the outer margin of the Core Treatment Areas will occur at 0,
1, 2, and 3 intervals of 0.4 kilometers (= .25 miles) each for a total of 4
samples over a combined distance of 1.2 kilometers (= 0.75 miles). These
samples will be taken along transects in approximate cardinal compass
directions of north, south, east, and west from the geographic centers of
the Core Treatment Areas.

To determine rates of infection of nymphs with Borrelia burgdorferi, a
sub-sample of 100 nymphs will be sent to the laboratory of Durland Fish at
Yale University School of Medicine to be tested with a fluorescent antibody
method.

C. Assessment - Estimating Efficacy
For each location, calculations of efficacy will be based on annual
comparisons of the density of each life stage sampled in a Core Treatment
Area versus a Control Site. Abbott's formula (Abbott 1925) will be used to
calculate percent corrected control of larvae, nymphs, and adult ticks. As
explained above, multiple sampling of tick density during peak periods will
be obtained for nymphs, and the principal estimate of the efficacy of the
treatment will be based on the reduction in the size of the nymphal cohort
of the population, because this is the life stage that is most often
responsible for transmitting Lyme disease to humans. The prevalence of
infection in nymphs also will be monitored to determine the impact of
treatment upon Lyme disease risk for humans.

Assay of Ticks for Human Pathogens - Ticks will be assayed for human
pathogens in the Vector Ecology Laboratory, Dept. of Epidemiology and Public
Health, Yale School of Medicine. Assays conducted at a centralized single
facility will provide consistent methodologies for comparison of pathogen
prevalence in host-seeking ticks among the project locations. Because adult
I. scapularis are rarely involved in B. burgdorferi transmission to humans
and A. americanum is an incompetent vector for this pathogen, only nymphal
I. scapularis will be assayed for B. burgdorferi. However, both nymphal and
adult I. scapularis will be assayed for the agent of human granulocytic
ehrlichiosis (HGE) because epidemiological evidence suggests that both
stages are involved in transmission to humans. Nymphal and adult A.
americanum will be assayed for the agent of human monocytic ehrlichiosis,
Ehrlichia chaffeensis, for similar reasons, although the epidemiology of
this disease is less well known.

Nymphal I. scapularis will be assayed for the presence of B. burgdorferi by
direct immunofluorescence microscopy. Midgut tissues are dissected on glass
slides, incubated over night at 37°C, fixed in acetone and then stained with
goat anti-B. burgdorferi antibodies labeled with FITC (Kirkegaard and Perry,
Gaithersberg, MD) at a dilution of 1:25. Binding is visualized under a Nikon
fluorescent microscope using cultured B. burgdorferi as a positive control.
A minimum of 50 nymphs will be assayed to determine the prevalence of B.
burgdorferi in host-seeking nymphal populations at both treatment and
control areas at each project location.

Nymphal and adult I. scapularis will be assayed for the agent of human
granulocytic ehrlichiosis by polymerase chain reaction (PCR). Preserved
ticks are thoroughly dried of preserving solution by blotting with filter
paper and then individually placed into separate sterilized Eppendorf tubes.
After freezing in liquid nitrogen, ticks are macerated using a sterilized
pestle and 100µl of TE buffer is added. DNA is extracted using Isoquick
Nucleic Acid Extraction kit (Orca Research, Inc. Bothell, WA). Primers EHR
521 and EHR 747 are used to amplify a 247-bp fragment of 16S rDNA and
amplification products are visualized in 2% agarose gels. Positive control
used for PCR is an HGE isolate (USG3) from Westchester County, NY maintained
in promyelocytic leukemia cell line HL-60. A minimum of 50 adults and 50
nymphs will be assayed to determine the prevalence of HGE in host-seeking
populations of each stage at both treatment and control areas at each
project location. Nymphal and adult A. americanum will be similarly assayed
for E. chaffeensis using primers HE1 and HE3 which amplify a 389-bp fragment
of the 16S gene of E. chaffeensis.

D. Technology Transfer
The fifth year of funding will be used for technology transfer to prepare
guidelines for use of the technology and in conducting meetings with the
public officials, public health professionals, pest control specialists, and
the general public to disseminate knowledge about the technology and its
applications. Final analysis, project evaluation, and preparations of
scientific publications will also occur the fifth year.

E. Program Management
Project Coordination- Management and coordination of the project will be the
responsibility of a team of Project Directors. The ARS team and Dr. Fish
will provide leadership and overall coordination of the project. Dr. Fish
will coordinate funding and project implementation through a Specific
Cooperative Agreement with ARS. Location Project Coordinators will be
responsible for conducting trials and gathering data at each location. Funds
to support the activities at each location will be distributed through
contracts with Yale University School of Medicine.
Project Directors -
John E. George, Ph.D.

Project Co-Director, USDA-ARS
J. Mathews Pound, Ph.D.

Project Co-Director, USDA-ARS
J. Allen Miller, Ph.D.

Project Co-Director, USDA-ARS
Durland Fish, Ph.D.

Project Co-Director, Consortium
Gary A. Mount, Ph.D.

Project Co-Director, USDA-ARS-CMAVE (Collaborator)
Location Project Coordinators -
Kirby Stafford III, Ph.D. and Anthony J. DeNicola

Connecticut Project Coordinator, Connecticut Agricultural Experiment Station
John F. Carroll, Ph.D.

Maryland Project Coordinator, USDA-ARS-LPSI
Terry L. Schulze, Ph.D. and Robert A. Jordan, Ph.D.

New Jersey Project Coordinators, Private Contractors
Thomas J. Daniels, Ph.D. and Richard C. Falco, Ph.D.

New York Project Coordinators, Fordham University
Thomas N. Mather, Ph.D.

Rhode Island Project Coordinator, University of Rhode Island
Collaborating Wildlife Specialists -
Anthony J. DeNicola, Ph.D.

White Buffalo, Inc.
Hamden, CT
Mathew C. Nicholson, Ph.D.

Center for Vector-borne Diseases
University of Rhode Island
Robert A. Jordan, Ph.D.

Wildlife Biology Consultant
Edison, NJ

Site-specific management
Operations all five project sites will be supervised by personnel who are
Certified Commercial Pesticide Applicators. Entomological studies at all
sites will be conducted or directly supervised by Ph.D. research
entomologists. Monitoring of deer movement and behavior and the darting,
trapping, and other handling of these animals will be conducted or
supervised by Ph.D. wildlife biologists. Project locations in individual
states will operate independently under the direction of the Location
Project Coordinators, and progress reports will be submitted on a regular
basis to the Project Directors. The Project Directors will monitor and
coordinate activities among the project sites to insure consistency in
methodology and progress. Meetings of all personnel will be held twice each
year to review progress and exchange information.

V. Anticipated Program Benefits
Community-based programs in which the '4-poster' is demonstrated to effect a
major reduction in the risk of tick bites would provide the first practical
area-wide method for protecting the public from tick-borne diseases. It is
anticipated that a successful project would result in the adoption of the
'4-poster' technology by government health agencies as well as private and
municipal vector control organizations for large-scale programs in
tick-borne disease prevention in the Northeast and other threatened regions
of the country.

VI. Facilities and Equipment
Consortium participants in New York, Rhode Island, and Connecticut maintain
long- established laboratories for research on ticks and lyme disease. These
facilities are well equipped with microscopes, computers, field vehicles,
collecting equipment and other materials related to this project. New Jersey
participants maintain private consulting firms that are less well equipped,
but adequate for the project. The laboratory at Beltsville is fully
equipped. All consortium participants have sites selected where pervious
studies on ticks and tick-borne pathogens have been conducted for many
years. Consortium participants have well-established relationships with
state and local health departments, state environmental and wildlife
agencies, and community leaders in the proposed study locations.
Adequate laboratory facilities are presently available to house Location
Project Coordinators and associates at each of the 5 state locations, yet it
will be necessary to purchase or perhaps rent several items. One Trimble
GeoExplorer II GPS unit with external power supply and ground plane antenna
will be purchased and passed among locations that do not have access to such
equipment. Units will be used to establish precise coordinates and altitudes
for individual '4-poster' devices and sampling plots. A solar powered video
trailer fitted with time-lapse 24-hour video recorders will be loaned from
the Knipling-Bushland U. S. Livestock Insects Research Laboratory in
Kerrville, TX. This unit also will be passed among participating locations
to permit unattended video-taping of deer and other animal behavior near
individual '4-poster' devices. In addition, pick-up trucks may need to be
rented to transport corn to fill devices at locations not having free access
to them. Also, it will be necessary to rent the use of a helicopter to
facilitate snow counts of deer as a means of determining deer densities at
all locations except perhaps in New Jersey.



Return to the KBUSLIRL homepage.


Does anyone have more information on this method of alien invasive
Borrelia burgdorferi control? What is the impact on the deer population,
for example? Are there any non-target impacts to take into account?

Marc

----- Original Message -----
NEWS


New Device Available for Control of Ticks Over Large Areas -

For installations that are interested in controlling ticks over large
acreages, while using extremely small amounts of pesticide, a new technology
is now commercially available - the '4-poster'! The US Army Environmental
Center (USAEC) Pest Management Team and the US Army Center for Health
Promotion and Preventive Medicine - North are assisting two Army
installations in getting this new technology operational on their
installations. The '4-Poster' Deer Treatment Bait Station is now
commercially available through a licensing agreement between the U.S.
Department of Agriculture (USDA), Agricultural Research Service (ARS), and
the American Lyme Disease Foundation.  This USDA patented device reduces
ticks over large acreages by treating deer with small quantities of an U.S.
Environmental Protection Agency (EPA) approved acaricide as the deer feed on
corn at the '4-Poster'.  Each '4-poster' will reduce ticks over
approximately 50 acres. USDA research has demonstrated control levels of
over 96% for Lyme disease ticks from use of '4-Posters' in five Area-wide
demonstration projects in CT, MD, NJ, NY, and RI.  One study site was on a
DoD installation.  This new technology provides installations with a viable
option for addressing control of ticks in a cost effective manner while
reducing the risk of tick-borne diseases to troops and dependents.



 The 4 Poster Deer Treatment Station

http://crdaniels.com/dandux/4post/intro.htm

Fight Lyme Disease and other tick transmitted diseases at their source.
Lyme Disease and other tick transmitted diseases have been documented
throughout the United States.  Now there is a way to fight them at their
source.

The White Tail Deer is the keystone host for the tick that transmits Lyme
disease.  By using the 4-Poster Deer Treatment Station an approved tickicide
can be applied to the head and neck areas of White Tail Deer while they
feed.  The head and neck area has been shown to be where 90% of the feeding
adult ticks are located on the deer.

Studies show that the use of the 4-Poster Deer  Treatment Bait Station with
approved tickicide has resulted in control of 92% to 98% of free living
ticks after 3 years of use with approved tickicide

How the 4-Poster works:  A central bin on the station is loaded and
maintained with whole kernel corn which acts as a bait and feed for the
deer.  As the deer feed at two application  / feeding stations located on
either side of the device, special rollers which contain an approved
tickicide apply the tickicide to the head and neck areas of the deer.

The 4-Poster Deer Treatment Bait Station was developed and patented by
researchers at the
United States Department of Agriculture

The 4-Poster Deer Treatment Bait Station is endorsed by the
American Lyme Disease Foundation
www.aldf.com

The 4-Poster Deer Treatment Bait and Feed Station is available exclusively
from
Dandux Outdoors
3451 Ellicott Center Drive
Ellicott City, Md 21043
email info at dandux.com