RODENT AND TICK-BORNE DISEASE SURVEY, CAMP RIPLEY, MINNESOTA, 20-24 MAY 1996 DEPARTMENT OF THE ARMY U.S. Army Center for Health Promotion and Preventive Medicine Direct Support Activity-West U.S. Army Garrison Fitzsimons Aurora, Colorado 80045-5001 [Seal of Department of Defense, United States of America] REPLY TO ATTENTION OF: MCHB-AW-ES (40-5f) 8 November 1996 RODENT AND TICK-BORNE DISEASE SURVEY NO. 16-RF-5132-96 CAMP RIPLEY, MINNESOTA 20-24 MAY 1996 1. REFERENCES. See Appendix A for a list of references. 2. AUTHORITY. USACHPPM Form 250-R, Minnesota National Guard, 8 April 1996. 3. PURPOSE. The purpose in performing this Survey was to sample the tick and rodent population for the infective agent, Borrelia burgdorferi, the causative agent of Lyme disease. In addition, tick and rodent sera samples were also tested for human granulocytic ehrlichia (HGE). Rodent sera was also tested for antibodies to Sin Nombre Virus (SNV), the human pathogenic hantavirus that causes hantavirus with pulmonary syndrome (HPS). See Appendix B for other assistance that can be obtained from the U.S. Army Center for Health Promotion and Preventive Medicine, Direct Support Activity-West (USACHPPM, DSA-W). 4. GENERAL. a. Mr. William E. Irwin, the Project Officer; MAJ Todd W. Walker, Chief, Entomological Sciences Division (ESD); SFC Eddie Curet, NCOIC, USACHPPM, DSA-W; and Mr. Jay Brizenka, Camp Ripley Training Site Environmental Specialist, conducted the Survey. b. The field survey portion of the Tick-borne Disease Survey was conducted at Camp Ripley during 20-24 May 1996. c. Laboratory analyses of ticks, rodent ear biopsies, and rodent sera were conducted between 7 June - 13 September 1996. 5. BACKGROUND. a. Lyme disease. (1) Lyme disease affects many organ systems and is caused by the spirochete, B. burgdorferi, which is transmitted to humans by the bite of an infected tick. Lyme disease has become the most prevalent arthropod- borne illness in North America. Its geographic range is expanding, and the number of reported cases continues to rise each year. The need to protect soldiers and other personnel working on Department of Defense installations has increased with the spread of Lyme disease. (2) During 1995, there were 269 cases of Lyme disease reported from the State of Minnesota to the Centers for Disease Control and Prevention (Appendix C); this is an increase of 29% from the reported cases in 1994. See Appendix D for reported cases of Lyme disease by county in Minnesota for 1995. (3) This Activity has been conducting Lyme disease surveillance at Camp Ripley since June 1989 (Appendix A, Reference 1). In June 1992, the presence of B. burgdorferi was confirmed for the first time in both the tick vector, I. scapularis, and the rodent population by growing these spirochetes in BSK II culture media (Appendix A, Reference 2). Ticks collected from deer during hunts in October and November 1992 produced positive I. scapularis by using fluorescent antibody (FA) staining, BSK II cultures, and Polymerase Chain Reaction (PCR) techniques (Appendix A, Reference 3). Additional ticks were collected from drags and off humans during the 1993 tick season as well as from deer hunts during October and November 1993. Positive ticks were found from 1993 deer hunt collections (Appendix A, Reference 4), from tick drags in 1994, and from off of humans in both 1994 and 1995. The most recent deer hunt survey conducted in 1995 produced 15 positive pools of I. scapularis using PCR (Appendix A, Reference 5). b. Ehrlichioses. (1) Other emerging tick-borne diseases that this Activity can assay from populations of ticks are human ehrlichioses. Over the past 10 years, these illnesses have infected over 570 people in the United States, Europe, and Africa; they have accounted for 16 fatalities in the United States alone (Appendix A, Reference 6). (2) Human ehrlichiosis was first diagnosed in 1985 from a man exposed to tick bites in Arkansas. It was not until 1990, however, that the agent of human ehrlichiosis was isolated from a patient at Fort Chaffee, Arkansas. Ehrlichia chaffeensis, as this organism is called, infects certain mononucular phagocytes and causes HME. (3) A second ehrlichia that was first recognized in Minnesota in 1990 invades granulocytic white blood cells and causes HGE. The agent that causes HGE is very similar to Ehrlichia equi, the pathogenic agent that causes equine ehrlichiosis (Appendix A, Reference 7). (4) The mortality of these two diseases of hospitalized patients are about 1 percent for HME and 5 percent for HGE (Appendix 1, Reference 8). Both HME and HGE are transmitted through the bite of an infected tick. The tick vector of E. chaffeensis is Amblyomma americanum in the south central and southeastern United States. In the northern part of the country (Connecticut, Minnesota, New York, and Wisconsin), the main vector of HGE is I. scapularis. There is increasing evidence that D. variabilis may be a competent vector of HGE (Appendix E). c. Hantavirus. (1) Since 1993, there have been 141 cases of hantavirus reported nationally. Hantaviruses throughout the United States have resulted in death in approximately 50 percent of the cases. A number of hantavirus cases have been diagnosed from preserved autopsy tissues, or by antibody testing of patients who exhibited hantavirus symptoms in the past. Rodents in the genus Peromyscus were especially targeted for capture and processing during this Survey because of this genus' involvement in hantavirus in the Four Corners Area of the southwest during the last three years (Appendix A, Reference 9). Peromyscus maniculatus, the deer mouse, has been implicated as the primary reservoir for the Four Corners Virus (FCV), or SNV as it is now called. Another hantavirus that has been confirmed to be pathogenic to humans is the Bayou virus which has been found in Oryzomys palustris, the Rice rat. Three cases of hantavirus have been confirmed to have been caused by Bayou virus by analyzing the human sera. (2) There are two types of hantaviruses; hantavirus with pulmonary syndrome (HPS), and hantavirus that causes hemorrhagic fever with renal syndrome (HFRS). Hemorrhagic fever with renal syndrome is mostly associated with human cases in Europe, and Asia (Korean hemorrhagic fever), while HPS has been confined to the New World. (3) There has been one confirmed case of HPS in Minnesota. 6. METHODS. a. Field Survey Procedures. (1) Tick Surveys. The tick collecting methods at Camp Ripley included tick flagging, drags, or walking. A 3x3-foot piece of white flannel cloth was dragged over the tops of large vegetation. Tick drags were used over grasses and over lower vegetation. Ticks were also collected from clothing while setting traps and just walking through the woods. At each collection site, attached ticks were removed from the cloth and placed in a labeled vial. Approximately 3400 linear meters were covered by team members doing the flagging, dragging or walking. Ticks were also removed from the ears of trapped rodents, one skink, and from Survey personnel. All ticks were kept alive by placing them in water- moistened vials and sent to the USACHPPM, DSA-W, ESD Laboratory. For each collection site or animal, all collected ticks were identified, counted, and separated into pools or processed individually. (2) Rodent Surveys. (a) Rodents were captured alive in Sherman traps (3x3x10 inches) on Camp Ripley. At each site, several trapping locations were selected, and one or more trap lines were set in each area. The traps were placed near the base of bushes and trees, near rodent burrows, and other areas showing evidence of rodent activity. Traps were located approximately 10-20 meters apart. The traps were set in the evening and collected before 0900 the next morning. Rodents trapped at Camp Ripley were identified in the field and later identifications were confirmed by The Museum of Southwestern Biology at the University of New Mexico. All rodents were handled in accordance with the guidelines outlined in the National Institutes of Health Publication No. 85-23, revised 1985, "Guide for the Care and Use of Laboratory Animals", and USACHPPM, DSA-W, ESD Animal Use Protocols. (b) Each rodent was anesthetized before removing any ticks, taking an ear biopsy, or sera. Each ear biopsy was placed in a labeled vial containing a glycerol/phosphate buffer solution and then frozen on dry ice. Rodent sera was taken by using a cardiac puncture. All samples were kept frozen until assayed for Lyme disease, HGE, or hantavirus. b. Laboratory Assay Procedures. (1) BSK II Cultures. (a) Forty-five I. scapularis, the deer or black legged tick, were processed for culturing. The resulting homogenate was inoculated into BSK II, a liquid culture media specifically developed to promote the growth of the spirochete that causes Lyme disease. (b) Twenty-four rodent ear biopsies were surface decontaminated and cultured in BSK II. Each inoculated culture was examined under the darkfield microscope for spirochete growth every seven days for a period of 21 days. If no spirochetes were found during this period, the samples were considered to be negative for B. burgdorferi. (2) Polymerase Chain Reaction. (a) Eighty-six pools of ticks were processed using PCR. These pools were set up with 1-10 ticks in each pool. A total of 175 D. variablilis and 88 I. scapularis were analyzed for Lyme disease and HGE. (b) Twenty-four ear biopsies were also tested for Lyme disease by Dr. David Persing's laboratory at the Mayo Clinic in Rochester, MN. 7. FIELD SURVEY DATA. a. Tick Collections. During the field portion of this Survey, 246 ticks were collected by drags, flagging, or off the clothes of survey personnel - - 119 I. scapularis and 127 D. variabilis. Seven ticks were found embedded on the Survey personnel -- 1 I. scapularis and 6 D. variabilis. Twelve ticks were collected from dry ice traps -- 1 I. scapularis and 11 D. variabilis. All the ticks mentioned above were adults. Seventy-seven ticks were collected from rodents -- 6 larval and 25 nymphal I. scapularis, and 46 larval D. variabilis. Also two larval and two nymphal I. scapularis were collected off a northern prairie skink. b. Rodent Collections. Five species of rodents were captured at 9 sites on Camp Ripley (see Table). The eastern chipmunk was the most common rodent captured. Table. Numbers of Ixodes scapularis and Dermacentor variabilis Ticks Removed from Rodents and Reptiles at Camp Ripley, Minnesota. --------------------------------------------------------------------------- Ixodes Dermacentor Collection Site No. Species scapularis variabilis --------------------------------------------------------------------------- Argonne Road 1 Tamias striatus 1N 0 (Site 1) 937067 (Eastern chipmunk) Gettysburg Road 3 Clethrionomys gapperi 0 0 (Site 2) 926074 (Redbacked vole) South of Old Ft. 3 Tamias striatus 0 0 Ripley Ruins (Eastern chipmunk) (Site 5) 938137 Arno Road (Site 8) 1 Glaucomys volans 1L 0 875251 (Southern flying squirrel) 2 Tamias striatus 0 0 (Eastern chipmunk) 1 Peromyscus maniculatus 1N 24L (Deer mouse) Foul Road (Site 12) 2 Tamias striatus 11N 0 946075 (Eastern chipmunk) North Ferrell Lake 1 Tamias striatus 2L1N 0 (Site 13) 906076 (Eastern chipmunk) 1 Peromyscus maniculatus 1L2N 21L (Deer mouse) South Ferrell Lake 4 Tamias striatus 6N 0 (Site 14) 904076 (Eastern chipmunk) 3 Zapus hudsonius 0 0 (Meadow jumping mouse) Cantonment Area 1 Peromyscus maniculatus 3L 1L (Site 16) 967051 (Deer mouse) Fort Ripley Road 1 Tamias striatus 3N 0 (Site 17) 938062 (Eastern chipmunk) Mississippi River 1 Eumeces septentrionalis 2L2N 0 Road (Site 18) (Northern Prairie skink) 966044 ---- --------------------- TOTALS 25 8L,27N 46L L-Larva, N-Nymph ------------------------------------------------------------------------ 8. LABORATORY RESULTS. Detailed information on the sites, species of ticks and rodents, and laboratory results are given in Appendix F. a. Ticks. (1) Six pools were positive for B. burgdorferi of the 86 pools of ticks that were analyzed using PCR techniques. Two pools of ticks collected from drags from Site-9, Kodiak Road were positive for the spirochete that causes Lyme disease--one pool of I. scapularis females, and one pool of D. variabilis females. A single I. scapularis male was positive from Site-10, a drag on the north end of East Boundary Road. A pool of 10 D. variabilis engorged larvae collected off a deer mouse, Peromyscus maniculatus, from Site-8, Arno Road, was positive. Two additional pools of I. scapularis females were positive, one from Site-12, Foul Road, and one from Site-17, Fort Ripley Road. (2) Two pools of ticks were positive for HGE using PCR. The same D. variabilis pool that was positive for Lyme disease spirochetes at Site- 9, and a pool of I. scapularis larvae taken off a P. maniculatus from Site- 16, the Cantonment area. (3) None of the tick pools cultured in BSK II showed any sign of spirochete growth. b. Rodents. (1) There were three positive ears from the rodents captured at Camp Ripley using PCR. One eastern chipmunk, T. striatus, from the south side of Ferrell Lake, a southern flying squirrel, Glaucomys volans, captured at the Arno Road site, and a single meadow jumping mouse, Zapus hudsonius, were positive for the spirochetes that cause Lyme disease. (2) All 24 rodent ear biopsies that were cultured in BSK II media for spirochetes were negative for B. burgdorferi. (3) All rodent sera was negative for hantavirus. 8. CONCLUSION. a. Lyme disease is endemic in Minnesota. Ixodes scapularis, the principal vector of Lyme disease in Minnesota, has been found in great numbers. Borrelia burgdorferi, the spirochete that causes Lyme disease, has been detected in both the rodent reservoir and tick vector populations at Camp Ripley. Human Granulocytic Ehrlichia was also detected in the tick population at Camp Ripley. There is evidence that HGE may be vectored by both I. scapularis and D. variabilis, as each of these species of ticks tested positive for ehrlichia. The use of personal protective measures is highly recommended to lower the risk of acquiring any tick-borne disease for all military, civilians, and dependents using Camp Ripley for outdoor training or recreation (Appendices G and H). b. Hantavirus was not found in the small sample of rodents that were tested from Camp Ripley. One case of hantavirus has been reported from Minnesota. Public education and awareness about hantavirus are the best methods of protection. Personnel exposed to rodent droppings or urine are at risk of acquiring hantavirus. Decontamination of rodent infested areas and rodent control will also reduce the risks of hantavirus infection. Personnel involved with rodent control or surveillance should be medically- monitored and use the proper personal protective equipment (Appendix I). c. The Camp Ripley Environmental Office has implemented an excellent educational and tick bite protective measure program that has greatly diminished the risk of personnel acquiring any tick-borne disease. [signature] William E. Irwin Biologist APPROVED BY: [signature] TODD W. WALKER MAJ, MS Chief, Entomological Sciences Division APPENDIX A REFERENCES 1. Memorandum, this Activity, HSHB-AW-P, 11 September 1989, subject: Pest Profile No. 16-66-0534-89, Lyme Disease Survey, Camp Ripley, Minnesota, 5-9 June 1989. 2. Memorandum, this Activity, HSHB-AW-P, 25 August 1992, subject: Lyme Disease Risk Assessment No. 16-66-AF29-92, Camp Ripley, Minnesota, 21-27 June 1992. 3. Memorandum, this Activity, HSHB-AW-P, 16 February 1993, subject: Lyme Disease Risk Assessment No. 16-66-A1CJ-93, Camp Ripley, Minnesota, 16 October 1992 - 8 February 1993. 4. Memorandum, this Activity, HSHB-AW-P, 23 March 1994, subject: Laboratory Lyme Results No. 16-66-A36W-94, Camp Ripley, Minnesota. 5. Memorandum, this Activity, HSHB-AW-P, 12 January 1996, subject: Laboratory Lyme Results No. 16-RF-4726-96, Camp Ripley Minnesota. 6. Walker DH, and JS Dumler, 1996, Emergence of the Ehrlichioses as Human Health Problems, Emerg. Inf. Dis., 2(1), pp 18-29. 7. Telford SR, JE Dawson, P Katavolos, CK Warner, CP Kolbert, and DH Persing, 1996, Perpetuation of the Agent of Human Granulocytic Ehrlichiosis in a Deer Tick-Rodent Cycle, Proc. Natl. Acad. Sci., 93, pp. 6209-6214. 8. Glynn K, V Kramer, and D Vugia, Human Ehrlichioses: New Emerging Tick- Borne Diseases in California, California Morbidity, January 1996. 9. Centers for Disease Control and Prevention (CDC), Morbidity and Mortality Weekly Report, Hantavirus Infection - Southwestern United States: Interim Recommendations for Risk Reduction. Vol. 42, No. RR-11, 30 July 1993. 10. U.S. Army Environmental Hygiene Agency, Technical Guide 148, January 1985, Commensal Rodent Control. APPENDIX B TECHNICAL ASSISTANCE Technical advice and/or consultation on pest management problems, to include on-site assistance, may be obtained by telephone from our Activity at DSN 943-8090. Please inform your Major Command Pest Management Consultant if you desire to request on-site assistance from our Activity. Technical services that we can assist you with are as follows: 1. Entomological laboratory support 2. Environmental laboratory support 3. Hazardous waste management 4. Industrial hygiene management 5. Medical systems safety and health 6. Sanitation and hygiene 7. Wastewater management 8. Water supply management 9. Worksite hazards management For assistance in any of the above listed programs, please call: Environmental Health and Engineering Division - DSN 943-8100 Field sanitation and hygiene; potable, recreational and wastewater quality; hazardous waste management; document/design reviews. Industrial Hygiene Division - DSN 943-8881 Industrial hygiene; hazard communication; protective equipment programs; document/design reviews. Environmental Laboratory Division - DSN 943-3293 Routine and emergency analysis of water, soil, and occupational health- related samples. During non-duty hours calls will be recorded by an answering machine and returned the next day. Many additional 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 CASES OF LYME DISEASE STATE OF MINNESOTA (REPORTED BY CDC) CDC Centers for Disease Control and Prevention June 14, 1996/Vol. 45/No. 23 MMWR MORBIDITY AND MORTALITY WEEKLY REPORT Lyme Disease -- United States, 1995 Lyme disease (LD) is caused by the tickborne spirochete Borrelia burgdorferi sensu lato. Surveillance for LD was initiated by CDC in 1982 and, during 1990, the Council of State and Territorial Epidemiologists designated LD as a nationally notifiable disease. For surveillance purposes, LD is defined as the presence of an erythma migrans rash greater than or equal to 5 cm in diameter or laboratory confirmation of infection with objective evidence of musculoskeletal, neurologic, or cardiovascular disease (1). This report summarizes cases of LD reported by state health departments to CDC during 1995 and indicates that the number of reported cases declined slightly from 1994. In 1995, 11,603 cases of LD were reported to CDC by 43 states and the District of Columbia (overall incidence 4.4 per 100,000 population), the second highest annual number reported since 1982 but an 11% decrease from the 13,043 cases reported in 1994 (Figure 1). As in previous years, the highest numbers of cases were reported from the northeastern, north- central, and mid-Atlantic regions (Figure 2). Incidences greater than 4.4 per 100,000 were reported by eight states, all in established LD-endemic regions (Connecticut [45.6], Rhode Island [34.9], New York [21.9], New Jersey [21.1], Pennsylvania [16.7], Maryland [9.2], Wisconsin [7.2], and Minnesota [5.8]); these states accounted for 10,640 (92%) of reported cases. In 1995, no LD cases were reported from Alaska, Colorado, Hawaii, Idaho, Montana, North Dakota, or South Dakota. Sixty-three counties each reporting greater than or equal to 20 cases accounted for 78% of all reported cases. Reported incidences were greater than 100 per 100,000 in 14 counties in Connecticut, Maryland, Massachusetts, Minnesota, New Jersey, New York, Pennsylvania, Rhode Island, and Wisconsin; the highest reported incidence was in Nantucket County, Massachusetts (838.8) (Figure 3). Compared with 1994, the number of LD case reports in 1995 decreased by 113 (89%) in Georgia, 82 (77%) in Delaware, 76 (58%) in Virginia, 51 (52%) in Oklahoma, 49 (48%) in Missouri, 126 (27%) in Rhode Island, 537 (26%) in Connecticut, and 1222 (24%) in New York. Reported cases increased by 580 (40%)in Pennsylvania and by 61 (29%) in Minnesota. In the remaining states, numbers of reported cases remained stable. The highest proportions of cases occurred among persons aged 0-14 years (2760 [24%]) and adults aged 35-49 years (2797 [24%]). Of 11,504 cases for which sex was reported, 5811 (51%) were male. Figure 1. Number of reported Lyme disease cases, by year - United States, 1982-1995 [Bar chart - data omitted] Reported by: State health departments. Bacterial Zoonoses Br, Div of Vector-Borne Infectious Diseases, National Center for Infectious Diseases, CDC. Editorial Note: The number of reported LD cases has increased steadily from 1982 through 1995, possibly reflecting increased recognition and reporting compliance and a true increase in incidence. The slight decline in the number of LD cases reported in 1995 from 1994 may have resulted from changes in these factors or a decrease in populations of Ixodes scapularis, the principal tick vector in the northeastern and north-central United States, as a result of variations in the environment. For example, light snowfall and dry spring conditions in Rhode Island during 1995 have been temporally associated with a 33% decline in the population of I. scapularis from 1994 (T. Mather, University of Rhode Island, Kingston, personal communication, 1996). Decreases in the number of reported LD cases in Georgia and Missouri may reflect 1) increased awareness among health-care providers that LD is not endemic in these states and 2) the possibility that some tickborne rashes may be related to another etiology. No cases in Missouri or the southern states have been confirmed by isolation of B. burgdorferi. An LD-like illness among some patients in Georgia and Missouri is characterized by a localized, expanding circular skin rash, similar to erythema migrans, and negative serology for B. burgdorferi (2). An uncultivable spirochete (B. lonestari sp. nov) identified in lone star ticks (Amblyomma americanum) collected from Missouri, New Jersey, New York, North Carolina, and Texas has been postulated as the possible etiologic agent (3). Figure 2. Number of reported Lyme disease cases, by state - United States, 1994 [Map - data omitted] Figure 3. Reported rates of Lyme disease, by county - north-central and northeastern United States, 1995 [Two maps - data omitted] Vaccines to protect against LD are in advanced stages of development and evaluation. However, personal protection measures (e.g., applying tick repellants and inspecting for ticks) and environmental modifications (e.g., applying insecticides and using deer fencing) will continue to be important methods for reducing the risk for exposure to tick bites and preventing LD and other tickborne diseases (e.g., ehrlichiosis and babesiosis) (4-6). To enable optimal treatment of patients, clinical and laboratory data must be used to distinguish between these diseases, and the possibility of co- infection with more than one agent should be considered (7,8). Early stages of LD usually are treated with amoxicillin or doxycycline; the treatments of choice for ehrlichiosis and babesiosis are tetracyclines and clindamycin/quinine, respectively (9). Participants in the Second National Conference on the Serologic Diagnosis of Lyme Disease (October 1994) recommended that laboratories use a two-test approach for the serologic diagnosis of LD. Specimens should be tested first by using the more sensitive enzyme-linked immunosorbent assay (ELISA) or indirect immunofluorescence assay (IFA). Specimens that are positive or equivocal then should be tested with the more specific lgG and lgM Western blot (WB). Because sensitivity and specificity of the ELISA and WB vary in relation to the timing of specimen acquisition, clinical and exposure histories must be considered in the interpretation of serologic results (10). References 1. CDC. Case definition for public health surveillance. MMWR 1990; 39 ( no. RR-13):19-21. 2. Campbell GL, Paul WS, Schriefer ME,Craven RB, Robbins KE, Dennis DT. Epidemiologic and diagnostic studies of patients with suspected early Lyme disease, Missouri, 1990-1993. J Infect Dis 1995; 172:470-80. 3. Barbour AG, Maupin GO, Teltow GJ, Carter CJ, Piesman J. Identification of an uncultivable Borrelia species in the hard tick Amblyomma americanum: possible agent of a Lyme disease-like illness. J Infect Dis 1996; 173:403-9. 4. Fish D. Environmental risk and prevention of Lyme disease. Am J Med 1995; 98:2-9. 5. CDC. Human granulocytic ehrlichiosis--New York, 1995. MMWR 1995; 44:593-5. 6. Meldrum SC, Birkhead GS, White DJ, Benach JL, Morse DL. Human babesiosis in New York state: and epidemiological description of 136 cases. Clin Infect Dis 1992; 15:1019-23. 7. Krause PJ, Telford SR, Spielman A, et al. Concurrent Lyme disease and babesiosis: evidence for increased severity and duration of illness. JAMA 1996; 275:1657-60. 8. Mitchell PD, Reed KD, Hofkes JM. Immunoserologic evidence of cooinfection with Borrelia burgdorferi, Babesia microti, and human granulocytic Ehrlichia species in residents of Wisconsin and Minnesota. J Clin Microbiol 1996; 34:724-7. 9. Benenson AS. Control of communicable diseases manual. 16th ed. Washington DC: American Public Health Association, 1995; 59-61, 165-7. 10. CDC. Recommendations for test performance and interpretation from the Second National Conference on Serologic Diagnosis of Lyme Disease. MMWR 1995; 44:590-1. APPENDIX D MINNESOTA DEPARTMENT OF HEALTH DISEASE CONTROL NEWSLETTER Volume 24, Number 4, June 1996 Lyme Disease Surveillance for Lyme disease is conducted to monitor trends both in the occurrence of Lyme disease over time and the risk of exposure by geographic area. The national surveillance case definition for a confirmed case of Lyme disease includes: 1) physician-diagnosed erythema migrans (EM) (solitary lesion must be greater than or equal to 5 centimeters in diameter), or 2) at least one late manifestation of Lyme disease (neurologic, cardiac, or joint) and laboratory confirmation of infection. MDH as established the following as acceptable criteria for laboratory confirmation with regard to counting surveillance cases: 1) positive results of serologic testing conducted by CDC or 2) a positive Western blot test from a clinical reference laboratory. As new testing methods such as polymerase chain reaction (PCR) probes become available, the surveillance case definition will be appropriately modified. A probable case is defined as an individual with at least one late manifestation of Lyme disease without a history of EM and laboratory evidence of infection but without appropriate laboratory confirmation. During 1995, 205 reports received from physicians or laboratories met the confirmed case definition. One hundred eighty-four (88%) of the confirmed cases had physician-diagnosed EM with individual lesions greater than or equal to 5cm. The other 21 cases had late manifestations of infection and were confirmed by positive Western blot. There were 105 probable cases reported. Of the 205 confirmed cases, 110 (54%) occurred in residents of the Twin Cities metropolitan area; however, most (52%) of these infections were likely acquired in Wisconsin or counties north of the Twin Cities, including Aitkin, Cass, Chisago, Crow Wing, Isanti, Itasca, Kanabec, Mille Lacs, and Pine counties (Figure 5). One hundred two (50%) cases occurred in males. The median age of cases was 34 years (range, 2 to 86 years). One hundred seventy-four (85%) cases experienced onset of illness between May 1 and September 30. APPENDIX E USACHPPM PUBLICATION JUST THE FACTS "HUMAN EHRLICHIOSIS" U.S. Army Center for Health Promotion and Preventive Medicine (Provisional) Just the Facts - Human Ehrlichiosis 16-007-1194 * Definition * Symptoms * Diagnosis and Treatment * Epidemiology * Prevention WHAT IS HUMAN EHRLICHIOSIS? (pronounced air-lick-ee-OH-sis) Human ehrlichiosis is a tick-borne illness that is caused by an extremely small type of bacteria known as "ehrlichiae." Human ehrlichiosis is just one member of a group of diseases known collectively as "ehrlichioses," so named because they are each caused by a different species of ehrlichiae. Ehrlichiae invade, and live within, white blood cells. They belong to the family Rickettsiaceae, genus Ehrlichia. Ehrlichiae are closely related to ricketsiae, the type of bacteria that cause Rocky Mountain spotted fever (RMSF). HISTORY Ehrlichiosis was first recognized in 1935 as a diease of dogs (canine ehrlichiosis) caused by Ehrlichia canis. In the 1960s a number of military guard dogs stationed in Vietnam died from this disease. Human ehrlichiosis is a more recently recognized illness. The first diagnosed case occurred in 1986 in a 51-year-old man from Detroit, who had been exposed to ticks in a rural area of Arkansas. In 1990, the agent of human ehrlichiosis was isolated from the blood of a U.S. Army reservist at Fort Chaffee, Arkansas. The new species of ehrlichiae was named E. chaffeensis. SYMPTOMS Symptoms of human ehrlichiosis begin in 1-21 (average 7) days following infection, and they resemble those of RMSF without a rash. Symptoms vary greatly in severity, ranging from an illness so mild that no medical attention is sought, to a severe, life-threatening condition. The most common symptoms are high fever, headache, chills, and muscular aches and pains, but may also include nausea, vomiting, loss of appetite, and an overall felling of bodily discomfort. A spotted rash similar to that seen in RMSF, although usually less prominent and more variable in appearance and location, is present in only 20-40 percent of cases. Since E. chaffeensis invades white blood cells, the body's immune system is adversely affected. This lessens the body's ability to fight other infections, and complications can quickly arise. In the most severe cases, kidney or respiratory failure occurs. There have been a small number of deaths. OTHER TYPES OF EHRLICHIOSIS Prior to the discovery of E. chaffeensis, E. sennetsu was the only Ehrlichia species known to infect humans. E. sennetsu causes Sennetsu fever, a mononucleosis-type illness first described in 1954, and occurring primarily in Japan. Sennetsu fever is very rare, and is usually extremely mild, with no deaths having ever been reported. Most recently, the Journal of the American Medical Association reported 12 cases of what may be a new type of human ehrlichiosis (termed "human granulocytic ehrlichiosis," or "HGE"), occurring in Minnesota and Wisconsin from 1990 through 1993. Two of the patients died from complications and secondary infections. The species that causes HGE has not yet been conclusively identified, but differs from E. chaffeensis in that it attacks a different type of white blood cell. While E. chaffeensis infects white blood cells known as monocytes, the HGE organism infects white blood cells known as granulocytes. Clinical symptoms of both infections are the same. Other species of Ehrlichia cause disease in animals, and include E. ewingii (canine granulocytic ehrlichiosis), E. risticii (Potomac Horse Fever), E. equi (disease in horses), and E. phagocytophila (disease in sheep and cattle). DIAGNOSIS AND TREATMENT A diagnosis of ehrlichiosis is confirmed by testing blood samples for antibody titers to different species of Ehrlichia, and by observing the bacteria in different types of white blood cells. The antibotic doxycycline is very effective for treating both human ehrlichiosis and HGE. Because ehrlichiosis can be so severe, or even deadly, it is very important to obtain early diagnosis and treatment. DISTRIBUTION The incidence of human ehrlichiosis is unclear. The Centers for Disease Control and Prevention (CDC) recorded 339 cases from 27 states for the period 1985 through 1993, primarily based on blood samples sent to them for testing. Most cases were from Arkansas, Georgia, Missouri, Oklahoma, Tennessee, Texas, and Virginia. HOW IS EHRLICHIOSIS SPREAD? Both human ehrlichiosis and HGE appear to be tick-borne. The suspected vector for human ehrlichiosis is the Lone Star tick, Amblyomma americanum. This tick is very common in the south central and southeastern United States, where the majority of cases of human ehrlichiosis have been acquired. It is less clear which tick species transmits the causative agent of HGE, but there is some evidence that the American dog tick (Dermacentor variabilis) or black-legged tick (Ixodes scapularis, also known as the deer tick) might play a role. The brown dog tick, Rhipicephalus sanguineus, is the most likely vector of canine ehrlichiosis. PREVENTION Help prevent human ehrlichiosis, and other tick-borne diseases, by protecting yourself from ticks. When you are in tick habitat (tall grass and weeds, scrubby areas, woods, and leaf litter), follow these precautions: * Wear the proper clothing - long pants tucked into socks or boots, long sleeve shirt, shirt tucked into pants, light-colored clothing to more easily spot ticks. * Perform frequent tick checks. Ticks are often found on the thigh, groin, arms, underarms, legs, and scalp. * Use a repellent containing permethrin on your clothing (NSN 6840-01-278- 1336, aerosol spray, or NSN 6840-010345-0237, individual impregnation kit for the field uniform) and a repellent containing deet (N,N-diethyltoluamide, NSN 6840-01-284-3982, long-acting lotion) on your exposed skin. * Remove attached ticks as soon as they are found. Use tweezers to firmly grasp the tick's mouthparts up against the skin, and pull back slowly and steadily. Be patient - the tick's central mouthpart, called the hypostome is covered with sharp barbs, sometimes making removal difficult. Don't pull back sharply, as this may tear the mouthparts from the body of the tick, leaving them embedded in the skin. If the mouthparts do break off, don't panic - the mouthparts alone cannot transmit disease because the infective body of the tick is no longer attached. However, to prevent secondary infection, remove the mouthparts as you would a splinter. Never squeeze the body of the tick or use such things as vaseline, fingernail polish remover, or a match while the tick is attached; these materials might agitate the tick and cause it to regurgitate infective fluid into the skin. * After removal, wash the wound site, and apply an antiseptic. SAVE THE TICK in a jar or plastic bag for identification should you later develop disease symptoms. Preserve the tick by either adding some alcohol to the jar or by keeping it in the freezer. Identification of the tick may facilitate the physician's diagnosis and treatment. * See a physician if you become ill after being exposed to ticks. --------------------------------------------------------------------------- Entomological Sciences Division U.S. Army Center for Health Promotion and Preventive Medicine (Provisional) Aberdeen Proving Ground, MD 21010-5422 DSN 584-3613 or Commercial 410-671-3613 email: mchbmre@aeha1.apgea.army.mil AEHA Form 326, 1 Oct 94 (MCHB-CS) --------------------------------------------------------------------------- APPENDIX F CAMP RIPLEY, MINNESOTA MAY 1996 TICK COLLECTIONS [Data omitted - data summarized in above report] 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 launderings. c. Insect Repellent Fabric Treatment (liquid, 5.1 fluid ounces), NSN 6840-01-334-2666. The contents are added to two 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, 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 launderings of mosquito netting, and six to nine months of treatment for tent fabric, depending on climate. 2. 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. 3. The U.S. Army Medical Department Tick-Borne Disease Card (7189) is available from the U.S. Army Center for Health Promotion and Preventive Medicine, Entomological Sciences Division. APPENDIX H LYME DISEASE RISK REDUCTION MEASURES 1. Emphasize public awareness programs to educate troops, dependents, civilian employees and visitors on personal protective measures and Lyme disease. Methods should include, but are not limited to: a. Distribution of printed Lyme disease handouts such as tick identification cards (USAMD-7189), pamphlets, and fact sheets. b. Notification in the installation newsletter, especially prior to the high-risk months (April through September). c. Making available for viewing video and 35mm slide format presentations on Lyme disease that are available from this Activity. 2. Submit any collected live tick specimens (both field-collected or ticks that have been removed from individuals) for identification and immunofluorescent staining or darkfield microscopy testing to the U.S. Army Center for Health Promotion and Preventive Medicine, Direct Support Activity-West Entomological Sciences Division, U.S. Army Garrison, Fitzsimons, Aurora, CO 80045-5001. 3. Stock Permethrin Arthropod Repellent (NSN 6940-01-278-1336, box of 12 cans for $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. 4. 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. 5. Identify high-risk foci in cantonment areas via tick dragging/flagging, small mammal trapping, deer checks and the assaying of collected ticks for Borrelia burgdorferi. Sampling should be performed in spring and summer when Ixodes scapularis nymphs (the life stage responsibile for most human Lyme disease infections) are active. Post DA Poster 40-5, and thereby identify high-risk areas. DA Poster 40-5 can be obtained by writing to the Commander, U.S. Army Center for Health Promotion and Preventive Medicine, ATTN: MCHB-MR-E, Aberdeen Proving Ground, MD 21010- 5422, or by telephone at DSN 584-3613 or Commercial (410) 671-3613. 6. Avoid high tick population areas for troop training or recreation. Such areas can be identified by dragging or flagging for ticks prior to use. Case-by-case surveillance is necessary due to the patchy distribution of I. scapularis 7. 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., August - November). 8. 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. ------------------------------------------ Trademark 3M is a registered trademark of Minnesota Mining and Manufacturing Co., St. Paul, MN 55133-3053 APPENDIX I REDUCING HANTAVIRUS RISK 1. The percentage of positive rodents from any particular trapping location may not represent the entire area. Geographic areas within the southwest have shown hantavirus infection rates in certain populations of P. maniculatus to be as high a 30 percent. The number of positive or negative rodents may vary from location to location, from species to species, and from one time of the year to another. 2. Public education and awareness about hantavirus are the best methods of protection. All personnel need to be aware of the dangers posed by hantavirus. All personnel potentially exposed to rodent droppings or urine should be aware of the possibility of acquiring hantavirus. Building surveys should be performed on a regular basis, and any indication of rodent activity should be addressed on every occasion. Anyone involved in cleaning rodent-infested buildings or handling dead rodents should use proper procedures. To control rodents, use the following suggestions. a. Rodent infestations in bunkers, warehouses, outbuildings, or any other structures can be controlled by the use of snap traps, glue boards, and anticoagulant bait. Detailed information on commensal rodent control is outlined in the U.S. Army Environmental Hygiene Agency Technical Guide 138, Commensal Rodent Control. b. All buildings should be rodent-proofed if possible. Eliminating ways rodents can enter buildings is a very important aspect of rodent management. Holes and cracks greater in size than 1/4 inch should be sealed with the appropriate construction materials (i.e. quick drying cement, reinforced wire mesh, or steel wool). Proper application procedures of these materials can be found in TG 138. c. Sanitation practices are essential in deterring rodents from entering buildings. All sources of food and water for rodents should be eliminated. d. Rodent surveillance should be conducted before occupying any infrequently used buildings. Inspections of equipment and supplies stored in these buildings should also be done prior to use of any materials. Occupied buildings should be inspected on a regular basis for evidence of rodent activity or infestations and any personnel noting rodent activity should report it to the proper authorities. 3. Almost every case of hantavirus can be traced to direct contact with rodents or contact with rodent infestations in enclosed buildings. Rodent urine and feces seem to pose the greatest health risk to people. Risk is increased when rodent droppings or urine are aerosolized in enclosed spaces such as buildings, bunkers, and warehouses. Personnel moving equipment, cleaning buildings, or otherwise disturbing deposited urine or feces may be at risk if not adequately protected. Areas with evidence of rodent infestations should be thoroughly disinfected and cleaned to reduce the likelihood of exposure to hantavirus-infected materials. Direct contact with rodent droppings may also be a means of transmitting the virus to humans. Cleanup procedures should be performed in a manner that limits the potential for aerosolization of rodent-contaminated dust and other materials. 4. Personnel training, working, or participating in events outdoors appear to be at a significantly lower risk of acquiring hantavirus infection than personnel exposed to rodent droppings or urine indoors. Lower risks of acquiring hantavirus outdoors as opposed to indoors are due to a number of factors, i.e., infected rodent excreta is less concentrated; winds will dissipate any aerosolized virus; direct sunlight will destroy any viable hantavirus when it is exposed for approximately 30 minutes; and, the density of field rodents outdoors is much less than that encountered indoors. People who can be considered at a higher risk might include pest controllers, wildlife biologists, contractors, plumbers, electricians, carpenters, maintenance workers, building inspectors, and workers involved in demolition or cleaning of old buildings. 5. Personnel tasked with inspections and cleanup of rodent contaminated buildings, and personnel identified as being at risk of acquiring hantavirus infection should be well instructed in preventive measures, symptoms of the disease and when to seek medical attention. A medical surveillance program for these people should include a medical history, a physical examination with attention to the pulmonary and renal systems, medical clearance for respirator use and baseline blood tests. A baseline serum sample for each worker at risk, drawn in a red-top tube, should be "on hold" and stored frozen (at -20 degrees C) for future analysis in the event it is needed. 6. To minimize the risk of hantavirus infection, personal protective equipment should be worn by those exposed to rodents or their droppings/urine. This equipment includes respirators with high-efficiency particulate air (HEPA) filters, goggles, solvent-resistant gloves, coveralls, and boots. Detailed guidance on personal protection for various classes of potentially-exposed individuals against hantavirus infection was published by the Centers for Disease Control and Prevention as a special report in the Morbidity and Mortality Weekly Report. The USAEHA Fact Sheets entitled, "Interim Recommendations for Reducing Risk of Hantavirus Infection," and "How to Protect Your Home, Pet and Family from Hantavirus Infection," provide additional guidance on this disease. 7. Areas with evidence of rodent infestations (i.e., rodent droppings, chewed materials, or nests) should be thoroughly cleaned to reduce the possibility of exposure to hantavirus-infected materials. Cleaning procedures must be performed in a manner that limits the potential for aerosolization of rodent contaminated dust and other materials. Follow these procedures when cleaning up rodent infestations. a. All personnel involved in cleaning should wear protective equipment and clothing -- individually fit-tested respirators with high -efficiency particulate air (HEPA) filters, goggles, solvent-resistant gloves, coveralls, and boots. b. Spray the floors and those portions of the walls of the buildings with a general-purpose disinfectant solution where evidence of rodent activities were present. Special attention must be given to dead rodents, rodent nests, droppings, food, or other items that have been contaminated by rodents; thoroughly soak these items with the disinfectant and place them into a double plastic bag. Use a shovel to remove the soaked material. Seal the plastic bags(s) when full or when the clean up is completed and dispose of as biological waste in accordance with the installations medical practices. Do not attempt to remove dry contaminated materials with a vacuum or by sweeping. c. Mop all floors with water containing a general-purpose disinfectant and detergent. Clean carpets and upholstered furniture by steam cleaning or shampooing with commercial-grade equipment. Spray all buildings with dirt floors with a general-purpose disinfectant before use. Remove rodent nests from furniture or equipment and decontaminate. The materials which cannot be decontaminated should be disposed of by burning or burying in accordance with the installations medical practices. d. Disinfect all work surfaces, storage cabinets, and drawers by washing them with a solution of water containing a general-purpose disinfectant and a detergent followed by an additional wiping down with disinfectant. e. Launder contaminated clothing and bedding in hot water and detergent. Items which cannot be laundered may be dry cleaned.