LYME DISEASE AND OTHER TICK-BORNE DISEASE RISK ASSESSMENT, FORT STEWART, GEORGIA, 23 OCTOBER - 27 DECEMBER 1993 DEPARTMENT OF THE ARMY U.S. Army Environmental Hygiene Activity - South Fort McPherson, Georgia 30330-5000 [Seal of Department of Defense, United States of America] REPLY TO ATTENTION OF: HSHB-AS-P LYME DISEASE AND OTHER TICK-BORNE DISEASE RISK ASSESSMENT NO. 16-08-A2SM-94 FORT STEWART, GEORGIA 23 OCTOBER - 27 DECEMBER 1993 1. REFERENCES. See Appendix A for a list of references. 2. AUTHORITY. Memorandum, U.S. Army Environmental Hygiene Agency (USAEHA), HSHB-M, 22 September 1993, subject: USAEHA Schedule of Field Services, FY94. 3. PURPOSE. The purpose of this risk assessment is to obtain host sera and ticks to provide a portion of the baseline data needed to develop a definitive Lyme and Other Tick-borne Disease Risk Assessment for Fort Stewart. When completed, this assessment can be used by field commanders to minimize risks of Lyme and other tick-borne diseases to military and civilian personnel. See Appendix B for other assistance that the U.S. Army Environmental Hygiene Activity-South (USAEHA-S) can provide. 4. GENERAL. a. Abbreviations and Terms. See Appendix C for a list of abbreviations and terms. b. Survey Personnel. Mr. Dennis Kuhr, Entomologist, Entomological Sciences Division (ESD), USAEHA-S coordinated this risk assessment with personnel at the Preventive Medicine Service (PVNTMED Svc), Medical Department Activity (MEDDAC). Individuals from the local PVNTMED Svc collected all the tick and sera samples. All specimens were sent to the USAEHA-S ESD, for processing. Mr. Jack Chandler, Jr., USAEHA-S Lyme Disease Program Manager, reviewed this report for technical content. c. Specimen Collection and Processing. (1) Blood Serum Samples. Whole blood was obtained from the body cavity of field-dressed white-tailed deer (Odocoileus virginianus) during the 1993 firearms season as they were brought to the hunter check-in station. The blood samples were centrifuged to obtain the needed sera which was kept frozen until it could be transported to Fort McPherson. Processing of the blood was done IAW TIM 26 (Appendix A, reference 2) and the USAEHA Standing Operating Procedure (Appendix A, reference 4) for specimen collection at deer check stations. Deer sera samples were sent packed in dry ice to the Veterinary Laboratory at Fort Sam Houston, Texas for serological examination for Lyme disease (Borrelia burgdorferi) and Rocky Mountain spotted fever (Rickettsia rickettsii). The USAEHA-S analyzed all the deer sera for prior exposure to human ehrlichiosis (Ehrlichia chaffeensis). (2) Tick Samples. The ears, nape and other regions of the deer were examined for the presence of ticks. Ticks were collected using fine-pointed forceps and placed in labeled vials. Each vial was identified with the collection date and sample number. The vials of ticks were kept cool after collection. Collected ticks were mailed to the USAEHA-S, ESD and processed by direct immunofluorescent assay (DIFA). BacTrace [Registered] affinity purified polyclonal antibody conjugate for Borrelia species, catalog number 02-97-92 and BacTrace affinity purified monoclonal antibody conjugate for Borrelia burgdorferi, catalog number 02-97-91, from Kirkegaard and Perry, Laboratories, Inc. was used. The polyclonal antibody conjugate was used to determine if they harbored any bacterial spirochetes of Borrelia species that may cause Lyme disease or another "Lyme-like" disease. Some researchers suggest there is a "Lyme-like" disease that is transmitted by another unidentified Borrelia species found inhabiting the midgut of ticks collected from the southern United States which is not the same causative agent (Borrelia burgdorferi) of the typical Lyme disease found in the northeast United States. Therefore the Borrelia species conjugate was used to detect all possible Borrelia species which may cause Lyme or "Lyme-like" disease. The monoclonal antibody conjugate was also used to determine if the specific spirochete for Lyme disease was present. -------- [Registered] BacTrace is a registered trademark of Kirkegaard & Perry, Inc., 2 Cessna Court, Gaithersburg, MD 20879. Use of trademarked names does not imply endorsement by the U.S. Army but is intended only to assist in identification of a specific product. 5. FINDINGS AND DISCUSSION. Lyme disease, Rocky Mountain spotted fever, and human ehrlichiosis are several tick-borne diseases which pose health threats at military installations. These diseases reduce the efficiency of affected military personnel and diminish the overall quality of life at installations. a. Blood Serum Samples. Serum samples were obtained from 63 white-tailed deer. None of the deer were seropositive for Lyme disease, 5.7 percent were seropositive for Rocky Mountain spotted fever, and 38.7 percent were seropositive for human ehrlichiosis. Deer sera analyses are furnished at Appendix D. b. Tick Samples. Ticks were collected from 65 of 99 deer sampled. More than 230 adult ticks and 15 tick nymphs were identified and assayed. The species collected, their life stages and the number testing postitive or negative for spirochetes are shown in Appendix E. Four species of ticks were collected; lone star tick [Amblyomma americanum (Linnaeus)], black-legged tick [Ixodes scapularis (Say)], winter tick [Dermacentor albipictus (Packard)], and the American dog tick [Dermacentor variabilis (Say)]. One lone star tick was found to contain Borrelia burgdorferi spirochetes. c. Tick-borne Diseases in Georgia. According to the Centers for Disease Control and Prevention (CDC), Morbidity and Mortality Weekly Report, January 7, 1994, Vol. 42, Nos. 51 & 52, Georgia had 43 cases of Lyme disease and 37 cases of Rocky Mountain spotted fever reported to the CDC in 1993. 6. RECOMMENDATIONS. Recommendations are made from the general findings of this report to ensure good PVNTMED practices which will reduce Lyme and other tick-borne disease risks to military, civilian, and visiting/ recreating personnel at Fort Stewart. General tick-borne disease reduction measures can be found at Appendix F. a. Fort Stewart - U.S. Army Forces Command. (1) Train installation personnel in the proper wearing of clothing and the use of repellents (see Appendix G) to minimize the threat of tick- borne diseases. Encourage Commanders at all levels to emphasize the use of the clothing repellent (NSN 6840-01-278-1336) and skin application repellent (NSN 6840-01-284-3982) to minimize potential exposure to tick- borne diseases. Avoid using those areas identified as having exceptionally high tick populations or with ticks heavily infested with spirochetes wherever possible. (2) Modify tick habitats by mechanical removal of leaf litter and brush when possible. Encourage the use of controlled burning in training areas as a vital part to the installations natural resource plan. Exercise care to prevent any adverse impact which may threaten the population of endangered species. (3) Follow installation professional wildlife biologist's recommendations to achieve annual deer harvest quotas in all training areas to ensure that the deer population is kept in check. Effective management of the deer population will reduce the associated tick population. (4) Post warning signs (DA Poster 40-5) at entrances to training areas to inform training area users that the threat of Lyme disease exists. (5) Perform chemical tick control in areas which are frequently occupied by troops and other land users. Examples of these areas include sites heavily used for ROTC summer camp field training, outdoor classroom instruction, or for special occasions by troops or Youth Services functions. Coordinate all requests for tick control with the Health Clinic and base all control operations on tick survey findings. b. PVNTMED Svc, Fort Stewart - U.S. Army Medical Command (PROV). (1) Emphasize public awareness programs to educate installation personnel and visitors to behavioral and personal protective measures available to reduce their exposure to Lyme and other tick-borne diseases. Encourage the use of a VHS 0.5-inch audio-visual tape entitled "Lyme Disease - A growing threat" (PIN 504494) by activities to educate their personnel. A "Just the Facts, Ticks and Tick-borne Diseases" is provided at Appendix H. (2) Perform tick surveys at sites frequently used for intensified troop training or recreation. See paragraph 6a(5) above for examples of suggested sites. (3) Send live ticks collected during tick surveys for Lyme disease analysis to the Commander, USAEHA-S, ATTN: ESD, Building 180, Fort McPherson, GA 30330-5000. 7. LABORATORY ASSISTANCE. The USAEHA-S will continue to identify and test any ticks sent to this Activity for the presence or absence of spirochetes. [signature] DENNIS D. KUHR Entomologist USAEHA-S Pest Management Program Manager APPROVED BY: [signature] JAMES W. JONES CPT, MS Chief, Entomological Sciences Division APPENDIX A REFERENCES 1. Conference Report on the National Defense Authorization Act for Fiscal Years 92 and 93, House Report 102-311, 102nd Congress, 1st Session, November 1991, p. 422. 2. Technical Information Manual (TIM) No. 26, March 1990, Lyme Disease- Vector Surveillance and Control. 3. Technical Guide (TG) 174, June 1991, Personal Protective Techniques Against Insects and Other Arthropods of Military Significance. 4. USAEHA, 8 October 1991, Standard Operating Procedure for Collection of Specimens at Deer Check Stations. 5. Technical Bulletin Medicine 561, June 1992, Occupational and Environmental Health Pest Surveillance. APPENDIX B TECHNICAL ASSISTANCE Technical advice or consultation on pest management problems, to include on-site assistance, may be obtained by telephoning our Activity, DSN 572-2564. Other services that we assist you with are as follows: 1. Entomological laboratory support 2. Pesticide equipment calibration 3. Pest management document review 4. Environmental laboratory support 5. Hazardous waste management 6. Industrial hygiene management 7. Sanitation and hygiene 8. Waste water management 9. Water supply management 10. Worksite hazards management For assistance in any of the above listed programs, please call: Entomological Sciences Division - DSN 572-2564 Environmental Health and Engineering Division - DSN 572-2727 Potable, recreational and waste water quality; hazardous waste management; document/design reviews. Industrial Hygiene Division - DSN 572-2827 Industrial hygiene; hazard communication; field sanitation and hygiene; protective equipment programs; document/design reviews. Laboratory Division - DSN 572-3236 Routine and emergency analysis of occupational health-related samples and environmental (water and soil) samples. During non-duty hours calls will be recorded by an answering machine (DSN 572-2564) and returned the next normal workday. Many additional occupational and environmental health related services are available from our parent organization, the U.S. Army Environmental Hygiene Agency, and are described in AEHA Pamphlet 40-2, Directory of Services (published annually). We will gladly coordinate any additional services you request and that we cannot provide, with our parent organization. APPENDIX C ABBREVIATIONS AND TERMS AEHA Army Environmental Hygiene Agency CDC Centers for Disease Control and Prevention DGSC Defense General Supply Center DIFA Direct Immunofluorescent Assay DSN Defense Switched Network ESD Entomological Sciences Division IDAA Individual Dynamic Absorption Application NSN National Stock Number PIN Personal Identification Number PVNTMED Svc Preventive Medicine Service TG Technical Guide TIM Technical Information Memorandum TSC Training Support Center USAEHA U.S. Army Environmental Hygiene Activity USAEHA-S U.S. Army Environmental Hygiene Activity-South VHS Video Home System APPENDIX D WHITE-TAILED DEER SERA COLLECTED AT FORT STEWART, GEORGIA [Data omitted by this typist - data summarized in above report] APPENDIX E DIFA ANALYSIS OF TICKS FROM DEER COLLECTED AT FORT STEWART, GEORGIA [Data omitted by this typist - data summarized in above report] APPENDIX F TICK-BORNE DISEASE RISK REDUCTION MEASURES 1. Emphasize public awareness programs to educate installation personnel and visitors on the potential for contracting tick-borne diseases such as Lyme disease and Rocky Mountain spotted fever and on personal protective measures which can be employed to minimize these risks. The USAEHA-S can provide brochures and other display materials. An informative VHS 0.5-inch audio-visual tape entitled "Lyme Disease - A growing threat" (PIN 504494) is available from the supporting Training Support Center (TSC). General Training Aid 8-5-56, Tick-Borne Diseases makes an excellent handout. Additional cards are available from USAEHA-S. An informative VHS 0.5-inch audio-visual tape about repellent application entitled "Application of the Arthropod Repellent System" (PIN 708575) and (TVT 8-232) is also available from the supporting TSC. 2. Submit any collected tick specimens (both field collected or ticks that have been removed from individuals) alive for identification and DIFA testing to USAEHA-S, Building 180, Fort McPherson, GA 30330-5000. USAEHA-S can provide directions and supplies for shipments of ticks. 3. Encourage individuals displaying Lyme disease symptoms such as febrile illness and rashes, to obtain prompt medical attention. 4. Stock Permethrin Arthropod Repellent (NSN 6840-01-278-1336, box of 12 cans), Insect Repellent Fabric Treatment (NSN 6840-01-334-2666, box of 12 bottles) and 3M [Trademark] Insect Repellent (NSN 6840-01-284-3982, box of 12 tubes) for distribution. Emphasize tick habitat avoidance and the proper wearing of clothing and use of repellents. 5. 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. Sampling should be performed in early summer when the ticks are active. Post DA Poster 40-5, and thereby identify high risk areas. 6. Avoid high tick population areas for troop training or recreation. Such areas can be identified by tick dragging or flagging prior to use. 7. Eliminate tick habitat in heavily used, infested areas (e.g., wooded recreation areas) by removing leaf litter and keeping grass mowed. Clearing should be performed during low-risk months (January/February) when the ticks are the least active. These measures will also discourage small mammals which may serve as hosts for the ticks. Thinning of trees and removal of brush will allow more sun penetration which will reduce the humidity level necessary for optimum tick survival. Prepare, as a contingency, to employ chemical control (use only approved pesticides) in the event that non-chemical control measures fail to reduce the tick population. 8. Follow installation professional wildlife biologist's recommendations to achieve annual deer harvest quotas in all training areas to ensure that the deer population is kept in check. Effective management of the deer population will reduce the associated tick population. --- [Trademark] 3M is a registered trademark of Minnesota Mining and Manufacturing Co., St. Paul, MN 55133 APPENDIX G REPELLENTS 1. Several repellent products 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 the uniform, they provide personal protection against a wide variety of medically important insect/arthropod pests. Availability and current pricing can be obtained by calling the DGSC at DSN 695-4865: a. Insect/Arthropod Repellent Lotion (cream, 2 fluid ounces). The lotion, NSN 6840-01-284-3982, is not labeled for ticks, but will repel chigger mites and many biting flies. b. Permethrin Arthropod Repellent, Insect Repellent, Clothing Application (aerosol, 6 ounces) NSN 6840-01-278-1336. Seventy-five percent of the can is used to apply to the field uniform and the remainder is used to treat mosquito netting. The product provides protection from ticks and mosquitoes through six normal washings. c. Insect Repellent Fabric Treatment (liquid, 5.1 fluid ounces) NSN 6840-01-334-2666. The contents are added to 2 gallons of water and applied with the 2-gallon sprayer from a field sanitation kit at a pressure of 50 pounds per square inch to field uniforms, mosquito netting, and tent fabric to provide protection from ticks and biting flies and other insects. Since most sprayers are not equipped with the required pressure gauge (NSN 3740- 01-332-8746), it will be necessary to obtain a pressure gauge and filter (NSN 4330-01-332-1639), in order to complete the retrofitting. Proper application can provide protection for the normal life of the uniform, six washings of mosquito netting, and 6-9 months of treatment for tent fabric, depending on climate. d. Insect Repellent, Clothing Application IDAA kit, NSN 6840-01-345- 0237. One kit treats one complete battle dress uniform. Treatment lasts for repeated (30 or more) washings. Note: Dry cleaning will remove the treatment. Mark advice code "2B" (no substitutions) when ordering this kit. 2. Detailed directions for the use of these and other repellents can be found in the TG 174, Personal Protective Techniques Against Insects and Other Arthropods of Military Significance. An informative VHS 0.5-inch audio-visual tape about repellent application entitled "Application of the Arthropod Repellent System" (PIN 708575) and (TVT 8-232) is also available from the supporting TSC. 3. Do not use tick or flea collars. A toxic reaction can result. Humans have sweat glands in their skin that serve as an avenue for chemical absorption. Dogs on the other hand, respire by panting, lacking sweat glands, In addition, pets have a thicker hair barrier than most humans to protect then from direct contact with the collars. 4. The following practices enhance the effectiveness of protection when used in conjunction with repellents: - Cover as much exposed skin as possible. Consider loose fitting long- sleeved shirts in summer. - Tuck pants inside socks or boots to keep out ticks. - Wear light-colored clothing to make ticks easier to see. - Plan ahead and treat clothing with permethrin before your outdoor activity begins. Permethrin binds with fabric and is persistent through several washings. - Store treated clothing in a plastic bag to help preserve repellent effectiveness and identify treated clothing. 5. The U.S. Army Medical Department Tick-Borne Disease Card (7189) is available from the USAEHA-S, ESD. APPENDIX H JUST THE FACTS U.S. Army Environmental Hygiene Agency Just the Facts - Ticks and Tick-borne Diseases 16-001-0593 * Identification * Geographic Location * Tick-borne Disease * Care of Tick Bites The following information will help you avoid tick-related problems as you live, train, work, or play in or around the grassy or wooded habitats where ticks are found. IDENTIFICATION Unlike insects, adult ticks have eight legs, relating them more closely with spiders and scorpions. The tick's body is also fused into a single region instead of having the head, thoracic, and abdominal regions typical of insects. There are two distinguishable families of ticks: (1) the hard ticks, which have hard smooth skin and an apparent head; and (2) the soft ticks with tough, leathery, pitted skin and no distinct head. The hard ticks are the ticks we most commonly find in the woodlands and on our pets. Soft ticks are generally less often observed and are found in caves and on birds. It is the hard ticks we associate with most of our common tick-borne diseases in the United States. For assistance in identifying ticks contact the local personnel in the pest control shop, Preventive Medicine Service, Health Clinic, or the Entomological Sciences Division, U.S. Army Environmental Hygiene Activity- South. GEOGRAPHIC LOCATION Keep in mind that not all ticks carry a tick-borne disease, so a tick bite does not necessarily mean that disease will follow. However, there are several ticks that are potential vectors of tick-borne diseases. In the Northeast and Midwest is the deer tick (Ixodes dammini), reported to be the same species as the black-legged tick (Ixodes scapularis); the western black-legged tick (Ixodes pacificus) and the Rocky Mountain wood tick (Dermacentor andersoni) in the West; the black-legged tick in the South; and the American dog tick (Dermacentor variabilis) and Lone Star tick (Amblyomma americanum), which are found throughout much of the United States. LYME DISEASE The causative agent of Lyme disease is the spirochete bacteria Borrelia burgdorferi. Frequency Lyme disease has become the most common tick-borne disease in the United States. Cases have been report in 48 states, with the greatest number of cases occuring every year in the northeastern states of Connecticut, Rhode Island, Massachusetts, New York, and New Jersey; in the upper midwest states of Wisconsin and Minnesota; and in the western states of California and Oregon. The disease is spreading rapidly, however, with an increasing number of diagnosed cases in the southeastern and southern states. Symptoms The most apparent and common symptom of Lyme disease, occuring in 50 to 65 percent of the cases, is a rash around the site of the tick bite. The rash appears within 3 days to 3 weeks after the bite and expands in a ring or bull's eye pattern, with the center area clear. Other complaints include flu-like symptoms, such as fever, chills, headache, and extreme fatigue. Although Lyme disease rarely causes death, the disease can cause a great deal of pain and discomfort if allowed to progress to later stages. If you have been in an area where ticks are found and you develop any of the symptoms mentioned above, especially during the period from May through early Fall, see a physician for evaluation immediately. ROCKY MOUNTAIN SPOTTED FEVER The causative agent of Rocky Mountain spotted fever (RMSF) is the rickettsial organism, Rickettsia rickettsii. Frequency RMSF was originally found in the Rocky Mountains, but is now much more abundant in the Southeast and South-central United States. Oklahoma, North and South Carolina, Virginia, West Virginia, Georgia, and Tennessee often lead the nation in the number of reported cases of this disease. Symptoms Usually the first symptoms of RMSF appear 3 to 14 days after the tick bite and include sudden fever, chills, muscle aches, bloodshot eyes, and headaches. There may also be nervous symptoms, such as sleeplessness, restlessnes, and delirium. In about 50 percent of the patients, a characteristic spotty rash occurs on the feet and hands within 2 to 3 days of the fever. The rash may move to the rest of the body, but does not start on the trunk of the body like the rashes caused by measles and some other disease. Although this disease can be effectively controlled with antibiotics following prompt treatment, fatalities do occur. HUMAN EHRLICHIOSIS Human ehrlichiosis is caused by the rickettsial organism Ehrlichia chaffeensis. Frequency Human ehrlichiosis was first reported from Arkansas in 1986. It has been found in at least 11 other southern states. Symptoms Symptoms of Human ehrlichiosis can be very mild to severe, requiring hospitalization, and include fever, chills, headache, aches and pains in the joints and muscles, loss of appetite, eye pain, nausea, and vomiting. There is usually no rash. PREVENTION Wear clothing properly. To greatly reduce your chance of tick bite, follow the DOD Repellent System of wearing proper clothing. Blouse or tuck your uniform legs into your boots and wear your sleeves down. Civilians should tuck their pant legs into their socks, and their shirt into their pants. Light colored clothing makes it easier to spot ticks. In addition, when in the field, "buddy up" and routinely check for ticks every few hours or as frequently as possible. After returning, remove your clothing and check your body carefully. Pay special attention to hairy or warm, moist parts of the body. Use repellants. The DOD Repellent System also recommends applying deet repellent, NSN 6840- 01-284-3982, to any exposed skin surfaces, and permethrin repellent spray, NSN 6840-01-278-1336, to your uniform or field clothing. NEVER USE PERMETHRIN ON YOUR SKIN. The permethrin repellent is best applied to clothing prior to wearing. Allow the repellent to dry before using the treated clothing. ONCE BITTEN If you find a tick embedded in your skin, do not squash or burn it. Use tweezers to grasp the tick's mouthparts as close to the skin as possible, and pull it straight outward. Pull slowly, firmly, and steadily. Because the tick's central mouthpart is long and covered with barbs, it can be difficult to remove. Be patient. The prompt and careful removal of attached ticks greatly lessens the possibility of obtaining a tick-borne disease. Wash the bite site and apply an antiseptic. Save the tick in alcohol or freeze it in a pill vial or plastic bag in case symptoms appear and identification of the tick becomes necessary. If symptoms do appear, seek medical attention immediately. --------------------------------------- Entomological Sciences Division U.S. Army Environmental Hygiene Activity-South, Ft. McPherson, GA 30330-5000 DSN 572-2564 or Commercial 404-752-2564 Nationally Recognized as the Center of Matrixed Occupational and Environmental Health Excellence AEHA From 326, 1 Dec 92 (HSHB-CS)