CLINICAL GUIDANCE DOCUMENT Please contact us at [email protected] or 1-866-623-6868 if you Management of Tick Bites and Investigation of Early Localized Lyme Disease have any questions or feedback about this clinical guidance document.

T I E N P A T

Symptomatic (3–30 days Tick bite but asymptomatic following tick exposure)

No risk of Lyme disease NO Is or was the tick attached? Does the patient have the following signs and symptoms compatible with Lyme disease? • Advise patient to monitor for signs and symptoms for 30 days YES Expanding typical or atypical Fever, chills, headache, stiff neck, fatigue, WITH OR erythema migrans rash > 5 cm WITHOUT decreased appetite, muscle and joint aches, Safely remove the tick, (see Box 1) swollen lymph nodes (see Box 2) if attached (see Box 3)

YES YES Is it a blacklegged tick? No risk of Lyme disease NO (see Box 3) Was the patient exposed to ticks in the past 30 days?

YES

Risk of Lyme disease is low NO Attached for ≥ 24 hours? YES POSSIBLY NO • Advise patient to monitor for signs and symptoms for 30 days YES Yes, residence or travel to risk No residence or travel to risk areas • Counsel patient on preventing No residence or travel to risk areas and contact with ticks but possible contact with ticks through areas and no possible contact exposure to ticks NO Tick acquired in risk or endemic through outdoor activities outdoor activities with ticks area with a prevalence of infected ticks > 20%? (See Box 4) Clinical case of Lyme disease Possible case of Lyme disease Low risk of Lyme disease, but do not rule it out At risk for Lyme disease, • Treat for early localized Lyme • Routine management of patient’s but post-exposure prophylaxis YES disease (see Box 8) symptoms • Consider alternative causes is not warranted • Lyme disease serology • Order Lyme disease serology of symptoms • Advise patient to monitor not indicated (see Box 6) • Consider Lyme disease serology, if clinically for signs and symptoms for Was the tick removed within the • If symptoms persist, • Consider treating for early localized NO indicated (see Box 6) 30 days past 72 hours? refer patient to appropriate Lyme disease (see Box 8) specialist • If symptoms persist, consider an alternative diagnosis. Consult Public YES Health to understand the local epidemiology. Refer patient to an appropriate specialist, as needed At risk for Lyme disease; optimal timing for post-exposure prophylaxis (see Box 5) • Advise patient to monitor for signs and symptoms for 30 days Box 1. Clinical Manifestations of Early Localized Lyme Disease: Erythema Migrans Rashes Box 6. Laboratory Testing Box 7. Sensitivity of Serological (Two-Tier) Testing† in Patients With Lyme Disease • Laboratory testing is not indicated for asymptomatic patients Additional images of typical and atypical Erythema migrans, acute phase 29–40% rashes are available on Health Canada’s • Serological testing may not yield positive results during (early localized disease) website; please see “Early localized Lyme early localized Lyme disease, so management should not disease (< 30 days).” be based on serological testing results during this phase Erythema migrans, convalescence phase‡ 29–78% Note: People with darker skin tones may • Antibiotic treatment in early disease may reduce (early localized disease) present with a bruise-like rash. seroconversion; testing should not be used to monitor treatment outcome • Following exposure to Borrelia burgdorferi, Neurological involvement (early 87% Box 2. Prevalence of Symptoms in Patients Box 3. Blacklegged Ticks at Various Stages and immunoglobulin M (IgM) antibodies are detected within disseminated disease) Presenting With Possible Early Localized Safe Tick Removal 2–4 weeks, and IgG antibodies within 4-6 weeks Lyme Disease# • Public Health Ontario uses a two-step testing algorithm to Arthritis (late disseminated disease) 97% • Erythema migrans rash • Headache 42% maximize sensitivity and specificity (see Box 7) (typical or atypical) ~70% • Fever/chills 39% • For serological testing, please complete the requisition • Fatigue 54% fully and submit it, along with samples, to a public health † • Stiff neck 35% Two-tier testing algorithm is based on serum sample initially tested using laboratory for testing • Myalgia 44% enzyme-linked immunosorbent assay (ELISA) method. If results of ELISA • Decreased appetite 26% • If European Lyme disease is suspected based on the method are reactive/indeterminate, separate IgM and IgG Western blot tests #As a disease of public health significance, Lyme disease is reportable in patient’s travel history, please order serology testing are performed. Ontario under the Health Protection and Promotion Act, R.S.O. 1990, c. H.7. adult female adult male nymph larva specific to European Lyme disease †Following antibiotic treatment. Box 4. Areas of Risk for Lyme Disease For more images, please go to: Centers for Disease Control and Prevention.

• The risk of acquiring Lyme disease varies across Box 8. Recommendations for Treatment of Patients With Early Localized Lyme Disease geographical regions. Please click to see the risks in Ontario, Canada, and the United States. Drugs Dosage for Adults Dosage for Children • In Europe, the areas of highest risk are in Central and Preferred Eastern Europe, but infected ticks have also been found in Southern Scandinavia and up to the northern Doxycycline 100 mg twice a day for 21 days Not recommended for children < 8 years of age Mediterranean region. Contraindicated for pregnant or For children aged 9–12 years of age < 45 kg: For instructions, please see Centers for Disease Control and Prevention. lactating people 5 mg/kg/day in 2 divided doses on day 1, followed by 2.5 mg/kg/day in 1 or 2 divided doses, for a total Box 5. Post-Exposure Prophylaxis of 21 days For severe infections, up to 5 mg/kg/day for 21 days The risk of developing Lyme disease following a tick bite National Urban Park and Morningside Park in the Greater by an infected tick is between 1% and 3%. In Ontario, the Toronto Area, Brighton, Kingston and surrounding areas, prevalence of infected ticks varies by geographic region. Thousand Islands, Brockville, Perth-Smiths Falls and Amoxicillin 1 g three times a day for 21 days For children ≤ 12 years of age ≤ 33 kg: In many instances, it is reasonable to adopt the “wait and surrounding areas, Ottawa and surrounding areas, and 30 mg/kg three times a day for 21 days see” approach and treat patients if they develop symptoms Rondeau Provincial Park in Morpeth*) compatible with Lyme disease. Counsel patients to watch for Cefuroxime 500 mg twice per day for 14–21 days For children > 8 years of age: 4. Doxycycline is not contraindicated (Doxycycline is the development of early signs and symptoms for 30 days, 30 mg/kg/day divided in 2 doses (maximum 500 mg/ contraindicated for pregnant people and for children and advise patients that other tick-borne infections may dose) for 14–21 days < 8 years old. There is insufficient evidence for the result in signs or symptoms too. prophylactic use of other medications, such as amoxicillin, Based on the best available evidence, post-exposure in these populations) For Allergy or Intolerance§ prophylaxis can be considered if these four criteria are met: Adults: 1 dose of doxycycline 200 mg, by mouth Azithromycin 500 mg/d for 17 days For children ≤12 years of age ≤ 50 kg: 1. The tick was attached > 24 hours Children ≥ 8 years: 1 dose of doxycycline 4 mg/kg, 10 mg/kg/day for 17 days 2. The tick was removed within the past 72 hours up to a maximum dose of 200 mg, by mouth

3. The tick was acquired in an area with a prevalence of ticks *Note: This is not a comprehensive list of higher-risk areas in Ontario. Clarithromycin 500 mg twice a day for 14–21 days For children > 8 years of age: infected with Borrelia burgdorferi > 20% (e.g., Rouge For more information, please refer to the Ontario Lyme Disease Map. 7.5 mg/kg twice a day (maximum 500 mg/day) for Relatively contraindicated in pregnant people 14–21 days Bibliography Aguero-Rosenfeld ME, Wang G, Schwartz I, Wormser GP. Diagnosis of Lyme National Institute for Health and Care Excellence. Lyme disease [Internet]. Erythromycin 500 mg four times a day for 14–21 days For children > 8 years of age: Borreliosis. Clin Microbiol Rev. 2005;18(3):484–509. London (England): The Institute; 2018 [cited 2018 May]. Available from: https://www.nice.org.uk/guidance/ng95 12.5 mg/kg four times a day (maximum dose 500 mg/ Cameron DJ, Johnson LB, Maloney EL. Evidence assessments and guideline day) for 14–21 days recommendations in Lyme disease: the clinical management of known tick bites, Wormser GP, Dattwyler RJ, Shapiro ED, Halperin JJ, Steere AC, Klempner MS, et erythema migrans rashes and persistent disease. Expert Rev Anti Infect Ther. al. The clinical assessment, treatment, and prevention of Lyme disease, human 2014;12(9):1103–35. granulocytic anaplasmosis, and babesiosis: clinical practice guidelines by the §Patients treated with macrolides should be closely monitored to ensure resolution of clinical symptoms as macrolides are less effective. Infectious Diseases Society of America. Clin Infect Dis. 2006;43(9):1089–134. Nadelman RB. Erythema migrans. Infect Dis Clin North Am. 2015;29(2):211–39. ISBN 978-1-4868-2399-4 (PDF) © Queen’s Printer for Ontario, 2018