LYME DISEASE PROFILE, FORT RITCHIE, MARYLAND, 24 NOVEMBER 1990 DEPARTMENT OF THE ARMY U.S. Army Environmental Hygiene Activity - North Fort George G. Meade, Maryland 20755-5225 [Seal of Department of Defense, United States of America] REPLY TO ATTENTION OF: HSHB-AN-P 08 APR 1991 LYME DISEASE PROFILE NO. 16-61-0509-91 FORT RITCHIE, MARYLAND 24 NOVEMBER 1990 1. REFERENCES. a. AR 40-5, Preventive Medicine, 15 October 1990. b. AR 420-76, Pest Management Program, 3 July 1986. c. USAEHA Publication, Lyme Disease Profile No. 16-61-0586-89, Fort Ritchie, Maryland, 26 November 1988. d. Fact Sheet No. 595, Lyme Disease Profile No. 16-61-0586-89, Fort Ritchie, Maryland, 26 November 1988. 2. AUTHORITY. AEHA Form 250-R, TRADOC, 25 October 1990. 3. PURPOSE. To assess the risk of Lyme disease to Fort Ritchie personnel by examining deer for the tick vector, Ixodes dammini and to assay ticks for the Lyme disease etiologic agent, Borrelia burgdorferi, IAW para 10-7.f., AR 40-5. 4. GENERAL. a. Personnel Contacted. See Enclosure (Encl) 1. b. Survey Conduct. The survey was conducted by Mr. Benedict Pagac, Entomologist, U.S. Army Environmental Hygiene Activity - North (USAEHA-N), Fort George G. Meade (FGGM), Maryland, on 24 November 1990. This survey was done in cooperation with the Maryland Department of Natural Resources (DNR). c. Survey Site. Fort Ritchie is located at the northeast corner of Washington County, Maryland, at the Frederick County border. Deer hunting was not permitted on Fort Ritchie proper. Many of the deer that were shot near Fort Ritchie were brought to the Maryland DNR hunting check station located on Maryland Route 15, Thurmont [approx. nine miles (14.4 km) east of Fort Ritchie] on the opening day of shotgun season (November 24). Deer brought to this station were examined for the purpose of this survey. d. Technical Assistance. Technical assistance or further informal advice may be obtained by contacting Mr. Benedict Pagac, Entomological Sciences Division (ESD), USAEHA-N, Commercial Phone 301-766-5281/6502 (DSN 923-5281/6502). 5. METHODS. a. Tick Collection. The heads, ears, and necks of 100 shot white-tailed deer (Odocoileus virginianus) were examined immediately before or after the weighing and tagging process. The hair was stroked contrary to the natural lay, using the hand edge, and ticks were removed from the exposed skin using fine-point (No. 5) jeweler's forceps. Examination time-per-carcass varied from two to eight minutes, with an average time of approximately four minutes per deer. Collected ticks were placed in labeled, 20 ml humidified vials and kept cool (1.5 - 4.5 degrees C). Ticks were returned to this Activity for identification and testing. b. Tick Testing. Ticks were assayed via Direct Fluorescent Antibody (DFA) testing to determine infection rates of the Lyme disease spirochete, B. burgdorferi. Assays were performed by personnel of USAEHA-N, FGGM, Maryland. c. Blood Samples. Blood pooled in the body cavities of 50 shot deer was collected using clean plastic (4 ml) disposable pipettes. Blood samples were not taken from carcasses that were rinsed with water or otherwise treated in a manner which might contaminate the sample. Samples were placed in 7 ml labeled tubes, spun, sera were separated, and frozen (-8.5 degrees C) until FA testing could be performed. Sera were tested by personnel of the Regional Veterinary Laboratory, Fort Meade, Maryland. 6. RESULTS. Tick collection, tick testing, and deer serum testing results are presented in Encl 2. Results from surveys performed by this Activity in the preceding two years (references 1c. and 1.d.) are also presented in Encl 2 for comparison. 7. DISCUSSION. a. Ticks. The 26 I. dammini specimens taken from nine deer during this survey reflects an increase in the number of deer having ticks and an increase in the total number of collected ticks, when compared with results obtained in 1988 and 1989. Furthermore, the six ticks which tested positive for B. burgdorferi spirochetes (23 percent) represent the first positive ticks obtained from deer in this region. b. Deer Serology. One positive deer serum sample was detected of 50 tested (2 percent) in 1990. A similar rate was recorded in 1989 (1/49 or 2 percent), whereas none were positive of 50 tested in 1988. c. Epidemiology. One hundred thirty-eight human Lyme disease cases were reported in Maryland in 1989, three of which were reported from Frederick County (reference 1.d.). No endemically-contracted human cases have yet been reported from the western Maryland counties of Washington, Allegheny, and Garrett. However, numerous cases were reported in 1989 from the more populated counties southeast of Fort Ritchie [e.g., Prince Georges (16), Anne Arundel (14)]. The majority of 1989 human Lyme disease cases per 100,000 population were reported from the upper tidewater counties of Kent and Queen Anne's (reference 1.d.). 8. CONCLUSIONS. I. dammini, the recognized vector of Lyme disease, was present in increasing numbers, on deer shot near Fort Ritchie during the 1990 fall hunting season. The causative agent for Lyme disease, B. burgdorferi, was detected in six tick specimens tested via DFA. One of fifty serum samples taken from white-tailed deer showed a positive antibody titer indicating exposure to the Lyme disease etiologic agent. This information, along with reports of three human Lyme disease cases contracted in Frederick County and 138 human cases reported statewide in 1989, suggests that, although still relatively low, the risk of contracting Lyme disease on or near Fort Ritchie, is increasing. 9. RECOMMENDATIONS. Recommendations are not keyed to, and do not stem from, specific operational deficiencies but are presented as a framework for an integrated Lyme disease management plan, based upon the results of this survey. a. Emphasize public awareness programs to educate troops, dependents, civilian employees, and visitors on personal protective measure and Lyme disease IAW paras 2-5.1.(2) and 2-6., AR 420-76; para 10-7.b. and 10-18., AR 40-5. Methods should include, but are not limited to: (1) distribution of printed Lyme disease handouts such as tick identification cards (USAMD-7/89), pamphlets, and fact sheets (copies provided to installation personnel). (2) notifications in the installation newsletter and post electronic media (e.g., closed-circuit TV) especially prior to the high-risk months (June-September). (3) making available, for viewing, video and 35mm slide format presentations on Lyme disease that have been previously provided by this Activity. b. Submit any collected tick specimens (both field-collected or ticks that have been removed from individuals) alive for identification and DFA testing to USAEHA-N, FGGM, MD 20755-5225 (para 10-7.f., AR 40-5). c. Stock Permanone [Trademark] (NSN 6840-01-278-1336, box of 12 cans $36.99) and 3M [Trademark] Insect Repellent (NSN 6840-01-284-3982, box of 12 tubes, $29.30) for distribution. Emphasize tick habitat avoidance and the proper wearing of clothing and use of repellents (para 10-18.a., AR 40-5). d. Report all confirmed and suspected cases of Lyme disease [e.g., suspicious febrile illnesses, arthralgias, rashes, (Erythema Migrans)] by special telegraphic report [MED-16(R4)] for all soldiers and civilian beneficiaries (para 3-2., AR 40-5). e. Monitor the risk of Lyme disease at Fort Ritchie by requesting, from this Activity, a follow-up deer check survey for fall of 1991 (Completed AEHA Form 250-R was forwarded to installation/MAJCOM personnel for review and signature)(para 10-7.f., AR 40-5). f. Identify high risk foci in cantonment areas via tick dragging/flagging, small mammal trapping, and tick assay for B. burgdorferi. Sampling should be performed in spring or early summer when I. dammini nymphs (the life stage responsible for most human Lyme disease infections) are active. Post DA poster 40-5, and thereby identify high risk areas [para 2-6.a.(1), AR 420-76; para 10-7, and 10-18., AR 40-5]. g. 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. dammini [para 2-6.a.(1), AR 420-76; paras 10-18. and 14-2.c., AR 40-5]. h. 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 or dragging prior to habitat modification. Clearing should be done in low risk months (i.e., January and February) [paras 2-5.k. and 3-2.c., AR 420-76; paras 10-7. and 14- 3.a.(3), AR 40-5]. i. Prepare, as a contingency, to treat high-use areas with pesticides to decrease tick numbers if surveillance reveals high tick numbers and if nonchemical control techniques (e.g., brush removal, mowing, raking) do not provide adequate control (paras 3-2.c. and 4-1.a., AR 420-76). --------- [Trademark] Permanone is a registered trademark of Fairfield American Corp., Rutherford, NJ 07070 [Trademark] 3M is a registered trademark of Minnesota Mining and Manufacturing Co., St. Paul, MN 55133-3053 [signature] BENEDICT B. PAGAC, JR. Entomologist Entomological Sciences Division APPROVED BY: [signature] JAMES T. KARDATZKE MAJ, MS Chief, Entomological Sciences Division Enclosure 1 PERSONNEL CONTACTED #1. Mr. Richard Downer, Chief, Environmental Health Section, PVNTMED Svc, Fort Meade MEDDAC, HSC *2. Mr. Ed Golden, Regional Manager, Forests, Parks, and Wildlife (FPW), MD DNR; Cumberland, MD *3. Dr. Martha Greko, DVM, Center for Veterinary Public Health, Maryland Department of Health and Mental Hygiene, Baltimore MD #4. Dr. John Hadidian, Urban Wildlife Specialist, National Park Service (NPS), U.S. Department of Interior (USDI), Washington D.C. *#5. Mr. Paul Mummert, Pest Controller, Directorate of Engineering and Housing (DEH), Fort Ritchie, USAISC #6. HMCS Maiuro, Medical Officer, PO Box 1000, Thurmont, MD #7. Mr. Roger Steintl, Park Manager, Catoctin Mountain National Park, NPS, USDI, Thurmont, MD ------------ * pre-survey coordination #post-survey telephonic discussion of preliminary results Enclosure 2 LYME DISEASE/TICK SURVEY RESULTS FORT RITCHIE, MARYLAND* THREE-YEAR SUMMARY 26 NOVEMBER 1988 25 NOVEMBER 1989 24 November 1990 Number 1988 1989** 1990 =========================================================================== Deer examined: 99 100 100 Deer having Ixodes dammini: 4 1 9 Ixodes dammini collected: 4 1 26 Ixodes dammini tested: 4 1 26 Ixodes dammini positive: 0 0 6 Deer blood samples tested: 50 49 50 Blood samples positive: 0 1 1 =========================================================================== *Collection site: MD State Deer Check Station, Mountain Gate Garage, Route 15, Thurmont (Fredrick Co.), Maryland Collector: Benedict B. Pagac, Jr. Deer sex/age: Majority were males, at least 1.5 years old. Deer locations: All deer were shot in Frederick County, MD; the majority within a 10 mile (16 km) radius of Thurmont or within 15 miles (24 km) east/southeast of Fort Ritchie. ** Survey conducted in support of the 1989 Maryland State-wide Deer Tick Survey. ===========================================================================