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Home My WebLink About20130418_Lyme Advisory (PDF)JEFFERSON COUNTY PUBLIC HEALTH 615 Sheridan Street  Port Townsend  Washington  98368 www.jeffersoncountypublichealth.org _____________________________________________________________________________________________ COMMUNITY HEALTH DEVELOPMENTAL DISABILITIES MAIN: (360) 385-9400 FAX: (360) 385-9401 ENVIRONMENTAL HEALTH WATER QUALITY MAIN: (360) 385-9444 FAX: (360) 379-4487 385 - - - 447 379 - - 940 385 - 9401 385 - - - Health Care Provider Advisory April 18, 2013 To: Jefferson County Health Care Providers From: Tom Locke, MD, MPH, Jefferson County Health Officer Re: Borrelia burgdorferi Detection in Clallam and Mason Counties Tick Surveillance in Washington State: For a number of years the Washington State Department of Health has been conducting tick speciation studies throughout the state. Citizens are asked to submit ticks specimen which are then identified according to species. These studies have demonstrated that the vector species for Lyme Disease transmission, Ixodes pacificus, is widespread in Washington State, including Clallam and Jefferson Counties. For the past two years DOH has been conducting another study in which submitted ticks are tested for 4 different tick-borne disease pathogens: Anaplasma phagocytophilum (Granulocytic Anaplasmosis), Borrelia burgdorferi (Lyme Disease), Babesia species (Babesiosis), and Ehrlichia chaffeensis (Monocytic Ehrlichiosis). In 2012, 380 tests were performed with 2 testing positive for Borrelia burgdorferi. One of these positive Borrelia burgdorferi specimens was from Clallam County in an Ixodes pacificus tick collected in the area due east of Lake Crescent known locally as Indian Valley. The other positive B. burgdorferi specimen in 2012 came from Mason County. In 2011, 2 out of 111 Washington State ticks tested positive for B. burgdoferi, both collected in Mason County. Lyme Disease Cases in Washington State: Confirmed Lyme Disease cases in Washington State are rare. In 2011 there were 19 confirmed cases statewide – 15 with out-of-state exposures, 1 with an international exposure, and 3 with Washington State-only exposures. In the previous 7 years (2004-2010), in-state exposure only cases ranged from 0-3 per year. Clallam County has not had a confirmed case of Lyme Disease reported although there have been anecdotal cases of rash illness following tick bites suggestive of tick-borne infection. In 2012 a probable case of Lyme Disease was reported in a Jefferson County resident without significant travel history. Clinical Manifestations of Lyme Disease: Following 24-48 hours of attachment by a B. burgdorferi infected tick, transmission of the spirochete bacteria begins to occur. The classical presentation of this infection, occurring in 60-80% of cases, is the “target” (aka “bulls-eye”) rash of Erythema Migrans (EM). The EM rash typically occurs in the first 7-14 days following infection. Systemic symptoms can develop during the 1-3 month period post-exposure including fevers, headache, swollen muscles and joints, and lymphadenopathy. Focal neuropathies such as COMMUNITY HEALTH DEVELOPMENTAL DISABILITIES MAIN: (360) 385-9400 FAX: (360) 385-9401 ENVIRONMENTAL HEALTH WATER QUALITY MAIN: (360) 385-9444 FAX: (360) 379-4487 385 - - - 447 379 - - 940 385 - 9401 385 - - 385 - - - 447 379 - - 940 385 - 9401 385 - - MAIN: (360) 385-9400 E FAX: (360) 385-9401 - ENVIRONMENTAL HEALTH WATER QUALITY MAIN: (360) 385-9444 FAX: (360) 379-4487 - Bell’s palsy can also occur during this period. Late manifestations include arthritis, meningitis, and cardiac conduction abnormalities. Diagnosis and Treatment: Serologic diagnosis can be complex and suffers from significant rates of false positive testing in low prevalence populations. A two step diagnostic testing algorithm is recommended by the Centers for Disease Control beginning with an EIA test, which, if positive, is confirmed with Western Blot of testing of IgM and IgG (if onset of symptoms is <30 days) or IgG alone (if onset >30 days). Other diagnostic tests are available (PCR, culture, urinary antigens) but suffer from poor sensitivity and specificity. Treatment of confirmed or probable Lyme Disease is with oral or parenteral antibiotics, depending on the stage of the disease. Conditions known as “post Lyme Disease syndrome” and “chronic Lyme Disease” have created an unusual element of controversy regarding Lyme Disease evaluation and management, with some practitioners making the diagnosis based on non-specific symptoms (chronic fatigue, joint pain, cognitive impairment) and prescribing prolonged courses of parenteral antibiotics. Controlled studies have failed to document the efficacy of antimicrobial therapy for these conditions and the CDC and IDSA (Infectious Disease Society of America) strongly discourage this practice. Prophylactic Antibiotics following Tick Exposure: Onset of a classical EM rash following a tick bite is a strong indication for antimicrobial treatment, with or without confirmatory testing. Serological tests can take up to 4 weeks to become positive after B. burdorferi infection. An argument can be made for prophylactic treatment of tick bites in certain circumstances. These include a tick bite from an area where Lyme Disease is endemic (>20% of ticks test positive for B. burdorferi), the tick is engorged (suggesting prolonged attachment), and prophylaxis can be started within 72 hours. Antibiotic prophylaxis generally consists of a single 200 mg dose of doxycycline in adults or 4mg/kg in children 8 years of age or older. Is the Olympic Peninsula an Endemic Area for Lyme Disease? The lack of confirmed Lyme Disease cases coupled with a single positive B. burgdorferi tick specimen (out of 11 tested over a 2 year period) does not qualify Clallam County as an endemic area for Lyme Disease. The detection of two ticks in Mason County and one tick in Clallam County with B. burdorferi infection raises the possibility that this pathogen is becoming established in the mouse population in some areas of the Olympic Peninsula. Typically mice serve as the reservoir host for B. burdorferi with the West Coast tick vector Ixodes pacificus. The East Coast/Midwest vector Ixodes scapularis transmits infection from reservoir populations of mice and deer. Clearly, ongoing tick sampling is needed on the Olympic Peninsula and efforts are underway to collect additional tick specimens for testing prior to the end of the grant period in June of 2013. Of special interest is the area around Lake Crescent where ticks have been known to be plentiful for many years. COMMUNITY HEALTH DEVELOPMENTAL DISABILITIES MAIN: (360) 385-9400 FAX: (360) 385-9401 ENVIRONMENTAL HEALTH WATER QUALITY MAIN: (360) 385-9444 FAX: (360) 379-4487 385 - - - 447 379 - - 940 385 - 9401 385 - - 385 - - - 447 379 - - 940 385 - 9401 385 - - MAIN: (360) 385-9400 E FAX: (360) 385-9401 - ENVIRONMENTAL HEALTH WATER QUALITY MAIN: (360) 385-9444 FAX: (360) 379-4487 - Recommendations: The best prevention of Lyme Disease (and other tick-borne infections) involves protective clothing, insect repellants, and daily inspection and removal of ticks when in “tick country”. The Lyme Disease vector, Ixodes pacificus is definitely resident in Clallam and Jefferson Counties. Over the past 2 years, 12 ticks were submitted from Clallam County for speciation and 8 were identified as Ixodes pacificus. In Jefferson County, 8 ticks were submitted over the same time period and 7 were identified as Ixodes pacificus. Prophylactic use of antibiotics is not recommended at this time following uncomplicated tick bites. Development of an EM rash 7-14 days following attachment by an engorged tick is a strong indication for 2 weeks of oral antibiotic treatment (doxycycline, ampicillin, or cefuroxime). Serological evaluation can also be valuable when signs and symptoms are present one or more months post-tick bite. Two stage testing should begin with an approved EIA test followed by a confirmatory Western Blot study if the EIA test is positive. All suspect, probable, or confirmed cases of Lyme Disease should be reported to the local health department. Excellent online resources are available for the evaluation and management of Lyme Disease at http://www.cdc.gov/lyme/healthcare/clinicians.html .