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Military Screen Finds Lyme in Florida
I treat pateints that come from many different states. I do feel that the density of Lyme differs from state to state, not based on useless and very rare reports by doctors, but based on the density of people working, living and having recreation near woods and shrubs with deer. While Lyme and its many co-infections are probably not as common in Florida as all the states to its north, it does occur in Florida. Many voting citizens in Florida have communicated the need for smart efforts to be made to educate Floridians who are in areas with increased risk, and they have been ignored or told silly things like, "Lyme is only on this military base in Florida, not anywhere else in the state."
Below is yet another sample of Lyme found in the State of Florida. It is ten years old. I am not able to comment on the type of lab testing done. (Some labs are better and many are worse since 1995. Some are worse because they use tests that look for less Lyme proteins, or they use labs which look for strains that are not in the region being tested.)
Some would have us believe ticks found near the base were trying to enlist to serve in the military. As I travel throughout my beloved Florida, I suspect some areas have less Lyme than others. Those areas that worry me are areas with wild grass and shrubs with the presence of many deer and small mammals. In those neighborhoods, I thing we need more education and awareness. I would prefer to be alert than in a fog.
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DEPARTMENT OF THE ARMY
U.S. Army Center for Health Promotion and Preventive Medicine
Direct Support Activity-North
Fort George G. Meade, Maryland 20755-5225
[Seal of Department of Defense, United States of America]
EXECUTIVE SUMMARY
PEST MANAGEMENT STUDY
NO. 16-07-3554-95
LYME DISEASE RISK ASSESSMENT FOR
EGLIN AIR FORCE BASE, FLORIDA
30 APRIL-5 MAY 1995
- PURPOSE. This study assesses the risk for military and civilian
personnel of contracting Lyme disease while engaged in outdoor
activities on Eglin Air Force Base (AFB), Florida.
- RESULTS. Sampling at Eglin AFB produced four Deer Ticks (Ixodes
scapularis), the vector responsible for Lyme disease (LD) transmission.
One of these ticks was positive for the LD agent (Borrelia burgdorferi).
Two American Dog Tick, Dermacentor variabilis, were recovered while
performing tick drags on the installation. This latter species can
produce a medical condition known as tick paralysis and may transmit a
number of human pathogens, including Rocky Mountain Spotted Fever. One
Lone Star Tick (Amblyomma americanum), the vector of human monocytic
ehrlichiosis, was collected.
- RISK. The risk of contracting LD at Eglin AFB is MODERATE. The
risks for Rocky Mountain Spotted Fever and Human Monocytic Ehrlichiosis
are LOW. We base these conclusions on the results of this survey and
information regarding human case reports and vector tick collection
records, from sites near Eglin AFB, from the Florida Department of
Health (FDOH).
- RECOMMENDATION. All military and civilian personnel using Eglin AFB
for outdoor training or recreation should use personal protective
measures (PPM), as addressed in Appendices C, D, and E, of this report.
These PMM will protect against tick bites, as well as the threat of
disease transmission and annoyance from other man-biting arthropods.
Personnel who find attached ticks on their bodies should carefully
remove them and send them to installation public health personnel for
identification. Additional surveys should be performed periodically
(every three to five years) to update this assessment as Lyme disease
and other arthropod and rodent-borne diseases are dynamic health
threats.
LYME DISEASE RISK ASSESSMENT NO. 16-07-3554-95
EGLIN AIR FORCE BASE, FLORIDA
30 APRIL-5 MAY 1995
- REFERENCES. See Appendix A.
- AUTHORITY.
- a. DoD Lyme Disease Surveillance Program, Armed Forces Pest
Management Board, October 1994.
- b. USAEHA Form 250-R, Armstrong Lab/OEMB, 20 Mar 95
- PURPOSE. To assess the risk of Lyme disease (LD) to Eglin Air Force
Base, Florida by performing environmental sampling for the tick vectors
of LD, especially Ixodes scapularis, and small mammals. Then to assay
ticks and mice for evidence of the LD etiologic agent Borrelia
burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner, in accordance
with Department of Defense Directive (DoD Dir.) 4150.7.
- GENERAL.
- a. Risk Definition. The term "risk", as used in this report, is a
non-statistical evaluation of qualitative and quantitative information
on LD locally. To the extent available, information evaluated included
the following elements:<
- History of LD in the area,
- The presence of the principal tick vector of LD (I.
scapularis) and host populations needed to sustain viable populations of
this vector,
- The presence of the LD-causing spirochete (B. burgdorferi) in
the local tick population, and
- The presence of antibodies against B. burgdorferi in the
blood serum of local mammal hosts.
Once gathered, this information was used to help determine the general
relative risk level as follows:
- Low - Some elements of the LD cycle have been identified nearby,
but not on the installation.
- Moderate - Some elements of the LD cycle have been identified from
the installation or human cases of LD have been reported
from the local area.
- High - All elements of the LD cycle have been found (are present)
on the installation.
- Personnel Contacted. The purpose and methodology of this survey
were dicussed with CPT Steven P. Nichoff and SGT Kevin T. Wilson, 96th
AMDS/SGPM, Eglin AFB.
- Survey Conduct. Samples were collected by Dr. Harold Harlan,
Direct Support Activity-North (DSA-North), using a protocol developed by
DSA-North and materials provided by this Activity (DSA-North). SGT
Wilson assisted in the conduct of the survey.
Technical Assistance. Technical assistance or further informal
advice may be obtained by contacting the Chief, Entomological Sciences
Division, this Activity, commercial (310)677-5281/6502 or DSN 923-
5281/6502.
5. BACKGROUND.
- Lyme disease (LD) is a multi-symptomatic infectious disease
caused by the spirochete, Borrelia burgdorferi Say [sic], which is
transmitted to humans by the bite of an infected tick. This disease is
usually called Lyme disease or Lyme arthritis in the United States.
Over the past few years, it has become the most prevalent arthropod-
borne disease in North America. Its geographic range is expanding and
the number of reported cases has continued to rise nearly every year
since 1989.
- The number of LD cases reported to the U.S. Centers for Disease
Control and Prevention (CDC), by the Florida Department of Health
(FDOH), have increased almost every year since 1985. In 1994, FDOH
reported 27 cases in 1994; however only 19 cases were reported in 1995
(references 4 & 5 Appendix A). The lack of a rapid, sensitive,
reliable, and cost-effective diagnostic test for LD results in proactive
treatment before case confirmation and, consequently, under-reporting.
The increased burden of reports on medical treatment facilities may also
be a factor. Personnel concerned with LD prevention and control should
not assume that human risk of LD has changed based solely on numbers of
reported cases.
- Epidemiologic information from the FDOH indicates that there were
no cases of LD reported from Santa Rosa, Okaloosa, and Walton Counties,
wherein Eglin AFB is located, in either 1994 and 1995. Florida
physicians have been reporting generally stable or gradually increasing
numbers of human LD cases to CDC.
METHODS.
- Environmental tick collection and testing. Ticks were collected
along trails and forest edges using tick drags and dry ice traps. They
were placed in vials and returned to this Activity to be identified.
When I. scapularis were collected, they were tested via direct and
indirect fluorescent antibody (DFA/IFA) techniques, as detailed by
Piesman et al. (1986; reference 8, Appendix A) for the presence of B.
burgdorferi.
- Small mammal collection and testing. Small mammal trapping was
performed under the authority of Florida Game and Freshwater Fish
Commission Scientific Collecting Permit No. WX95098-1995, using Sherman
Live Traps (H.B. Sherman Traps, Inc., Tallahassee, FL). Approximately
50 traps were set out each evening during the period 30 April - 5 May
1995 and collected the following morning. When small mammals were
collected, they were anesthetized and then examined about the eyes,
ears, necks, and posterior for the presence of ticks. When ticks were
detected, they were pulled off using fine-tipped forceps, placed into
plastic vials, and forwarded to this Activity (DSA-North) for
identification and possibly further testing.
RESULTS. (Also see Appendix B) A total of four Deer Ticks (Ixodes
scapularis) and one Lone Star Tick (Amblyomma americanum) were collected
by tick drag at Eglin AFB during the period 30 April - 5 May 1995. No
ticks were collected by dry ice traps. Two white-footed mice
(Peromyscus leucopus) were collected during the survey. Two American
Dog Ticks (Dermacentor varibilis) were collected from one of the mice.
One of the four I. scapularis was found to be infected with Borrelia
burgdorferi, the Lyme disease causal agent. The other three I.
scapularis and one D. varibilis were positive for nonspecific
spirochetes (not B. burgdorferi).
DISCUSSION. The discovery of a deer tick infected with the LD-
causing spirochete indicates the potential for human cases. The very
low endemic deer tick population reduces the potential for human
exposure. Florida maintains a very low incidence of human Lyme disease
cases. Most of these cases are thought to have been people who became
infected elsewhere, but were not diagnosed until their return to
Florida. The presence of sandy, well drained soils in Florida, as a
whole, are not conducive to maintaining the vector tick populations.
Historically it has been thought that the presence of imported fire ants
(Solenopsis invicta) has negatively impacted tick populations in
Florida. During this survey, it was very rare to even encounter a tick
on the western 2/3 of the Eglin Reservation. However, Lyme disease and
other rodent and tick-borne diseases are among the emerging diseases of
concern to public health officials throughout the U.S. Conducting
periodic health threat assessments (every 3-5 years) of the arthropods
and small mammals found on Eglin AFB would give the command a good grasp
of the disease risk on the installation.
CONCLUSIONS. Despite the discovery of the LD pathogen in a deer
tick during this study, the low incidence of human Lyme disease cases in
the Florida panhandle, together with the low density of ticks, support
the conclusion that the risk of contracting LD on Eglin Air Force Base,
FL is MODERATE, and probably stable. Risk for Rocky Mountain Spotted
Fever and Human Monocytic Ehrlichiosis are LOW.
RECOMMENDATIONS.
- Periodically remind and retrain all military and civilian
personnel at Eglin AFB concerning the information on repellents in
Appendices C, D, and E of this report.
- Assist this Activity, or take other steps, to ensure the conduct
of periodic (suggested every 3-5 years) surveys of deer, small mammals,
or the environment for host-seeking ticks, and evidence of the presence
and prevalence of B. burgdorferi and other tick-borne pathogens, to
determine the risk level of contracting LD, RMSF, or ehrlichiosis at
Eglin AFB.
- Have persons with a history of tick bite or exhibiting suspicious
symptoms report to a health care provider as soon as possible. If
attached ticks are provided to installation public health personnel,
species determination can be made.
ADDITIONAL ASSISTANCE. Additional direct support in the fields of
pest management, pesticide risk management, water supply management,
wastewater management, hazardous waste management, worksite hazards
management, health care hazards management, ergonomic evaluation,
sanitation and hygiene, and installation industrial hygiene management
is available, and may be requested from USACHPPM, DSA-North at DSN 923-
6502/5281/6205, or commercial (301)[677-]6502/5281/6205.
[signed by]
RICHARD N. JOHNSON
MAJ, MS
Chief, Entomological Sciences Division
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APPENDIX A
REFERENCES
- AR 40-5, Preventive Medicine, 15 October 1990.
- DoD Directive 4150.7, Department of Defense Pest Management Program,
24 October 1983.
- Armed Forces Pest Management Board Technical Information Memorandum
No. 26, Lyme Disease: Vector Surveillance and Control, March 1990.
- Centers for Disease Control and Prevention. Lyme Disease-United
States, 1994. MMWR, 44(24): 459-463. 23 June 1995.
- Centers for Disease Control and Prevention. Lyme Disease-United
States, 1995. MMWR, 45(23): 481-484. 14 Jun 96.
- Barbour, A. G., S. L. Tessier, and W. J. Todd. 1983. Lyme disease
spirochetes and ixodid tick spirochetes share a common surface antigenic
determinant defined by a monoclonal antibody. Infect. Immunol., 41:
795-804.
- Oliver, J.H., M.R. Owsley, H.J. Hutcheson, A.M. James, C. Chen, W.S.
Irby, E.M. Dotson, and D.K. McLain. 1993. Conspecificity of the ticks
Ixodes scapularis and Ixodes dammini (Acari: Ixodidae). J. Med.
Entomol., 30(1): 54-63.
- Piesman, J., T. N. Mather, S.R. Telford III, and A. Spielman. 1986.
Concurrent Borrelia burgdorferi and Babesia microti infection in nymphal
Ixodes dammini. J. Clin. Microbiol. 24: 446-447.
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APPENDIX B
DATA SUMMARY SHEET
DOD LYME DISEASE RISK ASSESSMENT
EGLIN AIR FORCE BASE
FLORIDA
30 April - 5 May 1995
# Ticks Collected – 7
# Ixodes scapularis[1] Collected – 4
# Rodents Collected – 2
# Human Lyme Disease cases 1994, Tri-county area[2] – 0
# Human Lyme Disease cases 1995, Tri-county area[2] – 0
# Human Lyme Disease Cases 1994, Florida[3] – 27
# Human Lyme Disease Cases 1995, Florida[3] – 19
------------------------------------------------------------------------
- Ixodes dammini Spielman, Clifford, Piesman, and Corwin and Ixodes
scapularis Say were synonymized by Oliver et al. (1993).
- Santa Rosa, Okaloosa, Walton Counties, FL includes all areas on Eglin
Air Force Base.
- Based on reference 4 & 5, Appendix A, of this report.
Table B-2. Identity of ticks collected on the installation through the
use of tick drags.
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| | Ixodes scapularis[1] | Dermacentor variabilis[1] | Amblyomma americanum |
| MALES | 3 | 0 | 0 |
| FEMALES | 1 | 0 | 1 |
| NYMPHS | 0 | 1 | 0 |
| LARVAE | 0 | 1 | 0 |
| |
| TOTAL | 4 | 2 | 1 |
1 One male I. scapularis positive for B. burgdorferi, other 3 I.
scapularis and larval D. variabilis positive for non-B. burgdorferi
spirochetes.
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APPENDIX C
Lyme Disease Risk Reduction Measures
- Emphasize public awareness programs to educate troops, family
members, civilian employees and visitors on personal protective measures
and Lyme disease (and other tick-borne diseases). Methods should
include, but not be limited to:
- Distribution of printed Lyme disease handouts, such as "tick-
borne diseases" cards (GTA-8-5-56), pamphlets, and fact sheets.
- Notifications in the installation newsletter, local media, and
post electronic media (e.g., closed-circuit TV), especially prior to the
high-risk months (April-July).
- Making the following videos available for general viewing: "Lyme
Disease: A Growing Threat (FAUPIN No. 504494DD, Army TVT No. 8-196) and
"Application of the Arthropod Repellent System" (No. 708575, Army TVT
No. 8-232).
- Submit tick specimens (both field-collected ticks and those removed
from individuals) alive for identification and DFA testing to USACHPPM,
DSA-North, Fort Meade, Maryland 20755-5225.
- Stock Permethrin Arthropod Repellent (NSN 6840-01-278-1336, box of
12 cans for $36.99), and 3M[1] Insect Repellent (NSN 6840-01-284-3982,
box of 12 tubes, $29.30) for distribution. Emphasize tick habitat
avoidance, proper wearing of clothing, and use of repellents.
- Report all confirmed and suspected cases of Lyme disease [e.g.,
suspicious febrile illnesses, arthralgias, rashes, (Erythema Migrans)]
through proper channels to both military and civilian public health
authorities.
- Identify high risk foci in cantonment areas via tick dragging/
flagging, small mammal trapping, deer checks and the assaying of
collected ticks for B. burgdorferi (or other human pathogens). Sampling
should be done in early summer when I. scapularis nymphs (the life stage
responsible for most human Lyme disease infections) actively seek hosts.
Post DA Poster 40-5, to identify high-risk areas.
- Avoid high tick population areas for troop training or recreation.
Such areas can be identified by tick dragging or flagging prior to use.
Case-by-case surveillance is necessary due to the patchy distribution of
I. scapularis and most other human disease vector ticks.
- Eliminate tick habitat in heavily used, infested areas (e.g., wooded
recreation areas) by removing low brush and leaf litter. Tick
infestations should be verified via tick flagging/dragging prior to
habitat modification. Clear such sites in low-risk months (i.e.,
January-February).
- As a contingency, prepare to treat high-use areas with pesticides
to reduce tick populations if surveillance yields large numbers of ticks
(especially if any are found to contain human pathogens) and if non-
chemical techniques (e.g., brush removal, mowing, raking) do not provide
adequate control.
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1 3-M is a registered trademark of Minnesota Mining and Manufacturing
Co., St. Paul, MN 55133-3053.
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APPENDIX D
REPELLENTS
- Several arthropod repellents are available through the Defense
General Supply Center (DGSC) or Self-Service Supply System. When
used in accordance with label directions and in conjunction with the
proper wearing of clothing, they provide personal protection against a
wide variety of medically important insect/arthropod pests.
Availability and current prices can be obtained by calling the DGSC
at DSN 695-4865 or commercial (804) 790-4865. Repellents available
for use are described below:
- Insect/Arthropod Repellent Lotion (cream, 2 fluid ounces),
NSN 6840-01-0284-3982. This is for application to exposed skin, is
not labeled for ticks, but will repel chigger mites and many biting
flies.
- Permethrin Arthropod Repellent, Insect Repellent, Clothing
Application (aerosol, 6 ounces), NSN 6840-01-278-1336. Approximately
75% of one can should be applied to each field uniform, and the
remainder used to treat other items (e.g., mosquito netting). This
product provides protection from ticks and mosquitoes for a maximum
of five weeks or five launderings. Apply more frequently if "buddy
checks" reveal attached ticks.
- Insect Repellent, Fabric Treatment (liquid, 5.1 fluid ounces),
NSN 6840-01-334-2666. The contents of one bottle are added to two
gallons of water and applied with a 2-gallon sprayer (like the ones
in field sanitation kits) at a pressure of 55 psi, to field uniforms,
mosquito netting, or tent fabric to provide protection from ticks,
biting flies, and other insects. Since many sprayers are not equipped
with the required pressure gauge (NSN 3740- 01-332-8746), it may be
necessary to obtain this type of pressure gauge and filter (NSN 4330-01-
332-1639), to retro-fit an available sprayer. Proper application,
followed by complete drying of the fabric, can provide protection for
the normal life of the uniform (180 days in the field), six launderings
of mosquito netting, or 6-9 months effectiveness for treated tent
fabric, depending on the climate of deployment site(s).
- Detailed directions for the use of these and other repellents can
be found in the U.S. Army Environmental Hygiene Agency Technical
Guide (TG) 174, Personal Protective Techniques Against Insects and
Other Arthropods of Military Significance, June 1991.
- The "Tick-Borne Diseases" cards (GTA 8-5-56) should be ordered
through normal military publications channels. Limited numbers of
these cards may be obtained from the Entomological Sciences Division,
USACHPPM, DSA-North, at DSN 923-5281 or commercial (301)677-5281.
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APPENDIX E
FACT SHEET - MOSQUITO AND TICK REPELLENTS
- Repellents containing DEET (N,N-diethyl-3-methylbenzamide, formerly
N,N-diethyl-m-tolumide) offer good protection against mosquitoes, and
are made for application to skin.
- Repellents containing Permethrin offer excellent protection against
ticks, and are formulated for application to clothing.
- DEET also offers protection against ticks, keeping them from
attaching to treated skin (sometimes for long periods). Ticks do not
generally attach in exposed areas, the primary areas to which DEET is to
be applied (refer to any given product's label directions).
- Permethrin, conversely, offers considerable protection against many
mosquito species, but it can't be applied to exposed skin (refer to any
given product's label directions), the main area(s) mosquitoes usually
bite. Permethrin is useful for treating bed netting and tents.
- Combined use of DEET on exposed skin (as for mosquito repellency)
and Permethrin on clothing (as for tick repellency) offers maximum
protection against both these (as well as many others). Always
read and follow the label directions before using any compound.
- Do NOT use flea or tick collars. A toxic reaction can result.
Humans have many sweat glands in their skin that can serve as avenues
for chemical absorption. Dogs (and cats), do not have sweat glands in
their skin and cool themselves by panting. In addition, most breeds of
these pets have a thick hair layer (barrier) whichprotects their skin
from direct contact with collars. Humans have very limited hair
covering.
- Various lotion products claim protection against mosquitoes.
Professional literature both supports and refutes benefits from lotions.
Controlled tests have shown that mineral oil, a major component of most
such lotion products, does reduce biting by several species of mosquitos
on areas of treated skin. However, this reduction in biting is small
when compared to the reduction by an equal amount of DEET in concurrent
tests by USDA labs.
- Controlled tests have shown that products containing high
concentrations of DEET (greater than or equal to 50%) do not offer
greater protection than products containing 30-50% DEET.
- The following practices enhance the effectiveness (degree of
protection) against mosquitoes and ticks when used in conjunction with
repellents:
- Cover as much exposed skin as possible. Consider wearing loose-
fitting long-sleeved shirts in summer.
- Tuck pants legs inside tops of socks or boots.
- Wear light-colored clothing to make ticks easier to see as they
crawl.
- Plan ahead and treat clothing with permethrin before starting your
outdoor activity. Permethrin binds with fabric and is persistent
through several detergent washings. ("Dry cleaning" will remove it
immediately.)
- Store treated clothing in a plastic bag to help preserve repellent
effectiveness, and to help identify which clothing has been
treated.
ALL BOLDING IS AN INSERT.
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