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A Guide to the Diagnosis of Tick-Borne Diseases

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A Guide to the Diagnosis of Tick-Borne Diseases Consider these tick–borne illnesses when the Vectors of Tick–borne Disease Tick Exposure following conditions exist: A Guide to the Hard ticks: Tick exposure includes a history of: The patient has visited • attached tick • the northeast US Amblyomma americanum (lone star tick), • tick found on clothing and/or hair Babesiosis (sporadic cases elsewhere) located primarily in the southern and south Diagnosis of • exposure to dogs or other animals Lyme borreliosis (most prevalent in the central states, can transmit ehrlichiosis, RMSF, • leisure activities in wooded areas (i.e. northeast, but occurs nationwide) Lyme borreliosis, and tularemia. TICK-BORNE • the southeast US camping or hiking) • outdoor employment (i.e. forest manage- RMSF (although occurs nationwide) Dermacentor andersoni (Rocky Mountain wood • the mountainous areas of the northwest ment) tick), located in the western and mountain DISEASES US or Canada CTF, TBRF states, can transmit CTF, RMSF, and tularemia. Preventive Measures • old cabins or caves TBRF Dermacentor variabilis (American dog tick), located throughout the US, except the Wear light-colored clothing so ticks are more Symptoms include mountain states, can transmit RMSF easily seen. • a malaria–like illness and tularemia. Wear long–sleeved shirts and long pants; tuck Babesiosis shirts into pants and pants into socks. Periodically examine skin, clothing, hair. Use • Bell’s palsy Ixodes pacificus (Western black–legged tick), insect repellants or acaracides applied to skin Lyme borreliosis, TBRF located along the Pacific coast, can transmit (i.e. DEET) or clothing (i.e. permethrin). • relapsing febrile episodes babesiosis, ehrlichiosis, and Lyme borreliosis. TBRF Inspect and remove ticks from pets frequently. • diphasic febrile episodes Ixodes scapularis (black–legged tick), located in CTF Proper Tick Removal • migratory joint pain the eastern US, can transmit babesiosis and Lyme borreliosis Lyme borreliosis. • ulcerated skin lesions Remove tick as soon as possible. Tularemia Soft ticks: Use tweezers to grasp tick at attachment site as close to skin as possible. • erythema migrans lesion Ornithodoros hermsi, located in the northwest- Gently pull tick straight out using slow, steady Lyme borreliosis ern states, can transmit TBRF. • maculopapular or petechial rash, extending pressure without twisting. to palms and soles If removal with the fingers is necessary, use a Ornithodoros turicata, located in the south- RMSF protective barrier. • diffuse maculopapular or petechial rash western and south central states, can transmit Avoid contact with tick fluids; do not crush, Ehrlichiosis TBRF. squeeze, or puncture the tick. Do not apply hot matches, nail polish, petro- Findings include leum jelly, or other chemicals to tick. • hemolytic anemia Carefully clean site with soap and water. Babesiosis Send ticks to the Texas Department of Health • leukopenia and thrombocytopenia Laboratories for testing. CTF, Ehrlichiosis • lymphadenopathy Tularemia • previous splenectomy Abbreviations for tick–borne diseases: Babesiosis CTF = Colorado tick fever Zoonosis Control Division RMSF = Rocky Mountain spotted fever TBRF = Tick–borne relapsing fever Stock No. 6-33 2/04 .
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