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Tick-Borne and Zoonotic Diseases in the United States David Spach, MD Professor, Division of Infectious Diseases University of Washington, Seattle. DHS/PP. North American Ticks. DHS/PP. Tick Quiz. 1. 2. From: Spach DH et al. N Engl J Med 1993;329:936-47. DHS/PP.
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Tick-Borne and Zoonotic Diseases in the United StatesDavid Spach, MDProfessor, Division of Infectious DiseasesUniversity of Washington, Seattle DHS/PP
North American Ticks DHS/PP
Tick Quiz 1 2 From: Spach DH et al. N Engl J Med 1993;329:936-47. DHS/PP
Important North American Ticks Ixodes Female (Adult) Ixodes Male (Adult) Ixodes Nymph Amblyomma Female (Adult) Dermacentor Female (Adult) Ornithodoros (Adult) From: Spach DH et al. N Engl J Med 1993;329:936-47. DHS/PP
Ixodes scapularis Ticks Adult Female Adult Male Nymph Larva Centimeter Scale From: CDC Lyme Disease Home Page. www.cdc.gov/ncidod/dvbid/lyme/ DHS/PP
Ixodes NymphTick From: Spach DH et al. Washington State Lyme Disease Monograph. DHS/PP
Ixodes Adult Females: Unfed and Fed From: Spach DH et al. Washington State Lyme Disease Monograph. DHS/PP
Case History: Question • A 17-year-old girl presented to the emergency room with lower extremity weakness. She had prolonged recent outdoor exposure. Her weakness was symmetrical and had begun about 8 hours prior to coming to the ER; sensation is intact. A tick is found embedded in her scalp. The most appropriate course of action is:1. Give IV ceftriaxone x 14 days2. Remove tick and observe closely3. Give IM streptomycin x 10 days4. Arrange for emergent plasmapharesis DHS/PP
Tick ParalysisClinical Features • Early Features- Paresthesias- Leg weakness- Absence of fever • Later Findings- Ascending paralysis- Ataxia- Hyporeflexia/Areflexia • Late Findings- Bulbar signs- Hypoventilation DHS/PP
Tick Removal DHS/PP
Case History • A 48-year-old woman presents with myalgias and a painful skin rash on her leg. She recently returned from a one week vacation in eastern Washington and says the rash began one day after she was bitten by something on her leg. The most appropriate course of action is:1. No antibiotics required2. Give PO Doxycycline for 14 days3. Give IV Ceftriaxone for 14 days4. Give IV Ampicillin and Gentamicin x 10 days DHS/PP
Case History DHS/PP
Tegenariaagrestis (Hobo Spider) Male Female From: http://hobospider.org DHS/PP
Recluse Spiders (Loxosceles sp) Distribution in US From: Vetter RS. DHS/PP
Diff Dx of Skin Lesions From: Young DM, et al. Arch Surg 2004;139:951-3. From: CDC & Prevention From: CDC & Prevention From: Darwin Vest From: Lowy FD. N Eng J Med 1998;339:520-32. DHS/PP
Case History • A 28-year-old man presented to clinic with a 16 cm erythematous, annular skin lesion on his right flank and flu-like symptoms. He spent the past 30 days hiking in the mountains. The most appropriate course of action is:1. Give PO Doxycycline for 14 days2. Reassure and don’t give antibiotics3. Draw serology (Lyme) and treat if positive4. Give IV Ceftriaxone for 14 days DHS/PP
Erythema Migrans Rash DHS/PP
Erythema Migrans Rash From: Steere AC. N Engl J Med 2001;345:115-25. DHS/PP
Lyme Disease: Erythema MigransTreatment • Preferred- Doxycycline: 100 mg PO bid x 14 days- Amoxicillin: 500 mg PO tid x 14 days- Cefuroxime: 500 mg PO bid x 14 days • Alternative - Azithromycin: 500 mg PO qd x 7-10 days - Clarithromycin: 500 mg bid x 14-21 days DHS/PP
Case History • A 43-year-old man from Westchester county, NY presents with fever and erythema migrans 7 days after a tick bite. He is started on amoxicillin, but 4 days later returns with headache, fever, and myalgias. Labs show leukopenia, thrombocytopenia, and increased hepatic aminotransferase levels. The most appropriate course of action is:1. Give high dose corticosteroids2. Give PO Doxycycline3. Give IV Ceftriaxone4. Give IV Gentamicin DHS/PP
Ehrlichiosis & Anaplasmosis in United States E. chaffeensisA.phagocytophiliumE. ewingii Amblyomma Amblyomma Ixodes Monocytes Granulocytes Granulocytes/Eos HME HGA HGE From: CDC Ehrlichiosis Home Page. www.cdc.gov/ncidod/dvrd/ehrlichia/Index.htm DHS/PP
Ehrlichiosis & Anaplasmosis • Human Monocytic Ehrlichiosis- Organism: Ehrlichiachaffeensis- Transmission: Amblyomma ticks- Cells: Monocytes/Macophages • Human Granulocytic Anaplasmosis- Organism: Anaplasmaphagocytophilium- Transmission: Ixodes ticks- Cells: Granulocytes DHS/PP
Ehrlichiosis: Laboratory Studies Liver Function Tests Platelet Count From: Fishbein DB et al. Ann Intern Med 1994;120:736-43. DHS/PP
Ehrlichiosis & AnaplasmosisTreatment • First Line- Doxycycline: 100 mg PO bid x 10 days • Second Line (Doxycycline allergy, Pregnancy)- *Rifampin: 300 mg bid x 10d *Since rifampin does not treat Lyme disease, patients should also receive amoxicillin or cefuroxime DHS/PP
Case History • A 67-year-old man from Wisconsin develops fever, severe malaise, and dark urine while visiting in Seattle. Two weeks prior he went on a 7-day hunting trip in rural Wisconsin. Labs show HCT = 31 & platelet count = 49,000. Optimal therapy would consist of:1. Ceftriaxone x 10 days2. Penicillin x 10 days3. Quinine + Clindamycin x 7 days4. Streptomycin x 7 days DHS/PP
Babesiosis: Treatment • First LineAzithromycin: 500-1000 mg PO day 1, then 250 mg PO qd x 6-9dplusAtovaquone: 750 mg PO bid x 7-10d ORClindamycin: 300-600 mg IV q6h (600 mg PO q8h) x 7-10 dplusQuinine: 650 mg of salt PO q8h x 7-10d DHS/PP
Case History • A 71-year-old geologist presents with a 3-day history of fever, chills, and myalgias. Seven days prior he was in rural eastern Washington and slept in an old cabin. Labs show hematocrit = 42, platelet count 67,000, and an abnormal blood smear. The most likely diagnosis is:1. Relapsing fever2. Lyme disease3. Leptospirosis4. Colorado tick fever DHS/PP
Relapsing FeverTreatment • First Line- Doxycycline: 100 mg PO bid x 7-10 days- DHS/PP
Tick-Borne Relapsing Fever in NorthwestNumber of Relapses From: Dworkin MS et al. Clin Infect Dis 1998;26:122-31. DHS/PP
Case History • A 29-year-old woman is admitted with suspected RMSF. Which laboratory study is NOT often observed with RMSF:1. WBC > 12, 0002. Platelet count < 150,0003. Hyponatremia4. Increased CSF WBC count DHS/PP
RMSF in US 1981-1992: Average Incidence by County From: Thorner AR et al. Clin Infect Dis 1998;27:1353-9. DHS/PP
RMSF: Clinical Manifestations From: Catherine Wilfert (Duke University Medical Center) DHS/PP
RMSF: Treatment • First Line- Doxycycline: 100 mg PO bid x 7-10 days • Second Line- Chloramphenicol • Promising • - Fluoroquinolones From: CDC RMSF Home Pagewww.cdc.gov/ncidod/dvrd/rmsf DHS/PP
Rabies DHS/PP
Case History: Question Silver-Haired Bat • A 29-year-old male is bitten on the shoulder by a bat and the bat escaped. What percent of Rabies Immune Globulin should be given at the wound site?1. 25%2. 50%3. 75%4. 100% DHS/PP
Rabies Postexposure ProphylaxisRabies Immune Globulin • “Administer 20 IU/kg body weight. If anatomically feasible, the full dose should be infiltrated around the wound(s) and any remaining volume should be administered IM at an anatomical site distant from vaccine administration. MMWR 1999;48 (RR-1): 275-9. DHS/PP
Rabies: Post-Exposure Prophylaxis • Wound cleansing • No RIG • +Vaccine: day 0 and 3 Previously Vaccinated Not Previously Vaccinated • Wound cleansing • *RIG • +Vaccine: day 0,3,7,14,28 *Administer vaccine as IM in deltoid+Administer full dose of RIG around wound if possible; remaining volume give at site distant from vaccine site From DHS/PP
Rabies: Post-Exposure Prophylaxis Not Previously Vaccinated • Wound cleansing • *Rabies Immune Globulin • +Rabies Vaccine: day 0,3,7,14 *Administer vaccine as IM in deltoid+Administer full dose of RIG around wound if possible; remaining volume give at site distant from vaccine site *Note: Number of recommended doses of rabies vaccine changed from 5 to 4 (ACIP June 24, 2009) From: CDC. MMWR 2008;57:1-26.
Case History: Question • In which of the following scenarios you administer rabies post-exposure prophylaxis:1. A 41-year-old woman is bitten by her neighbor’s dog 7 days ago while jogging by their house; the dog is behaving normally2. A mother awakens and finds a bat in the room of her 4-year-old child (and the bat escapes3. A 22-year-old man picks up a dead bat in his yard (with bare hands) and throws it down into a large ravine4. A 48-year-old man tells you during a routine medical visit that he suffered a unprovoked dog bit in Thailand 3 months ago DHS/PP
Case History: Question • A 49-year-old woman is admitted to the hospital with a suspected diagnosis of hantavirus pulmonary syndrome. Which of the following would be LEAST characteristic of the clinical presentation of hantavirus pulmonary syndrome? 1. CSF pleocytosis 2. Increased hematocrit 3. Increased white blood cell count with immature forms 4. Thrombocytopenia DHS/PP
Hantavirus Pulmonary Syndrome: Reservoir Peromyscus maniculatusDeer Mouse Source: CDC and Prevention DHS/PP
*Hantavirus Pulmonary SyndromeThrough November 11, 2009 Source: CDC and Prevention *By State of Exposure DHS/PP
Hantavirus Pulmonary Syndrome: Chest Radiograph Early Stage Severe CDC Later Stage Interstitial DHS/PP
Hantavirus Pulmonary SyndromeProgression of Disease Recovery Prodrome Cardiopulmonary Death Picture DHS/PP
Dog & Cat Exposure DHS/PP
Case History: Animal Bite • A 33-year-old woman living in Washington State is bitten on her hand by her cat while trying to break up a fight between her cat and dog. One day later her wound is red and painful and she comes to the ER for evaluation. Which ONE of the following is TRUE? 1. Her risk of getting rabies from this cat bite is about 2%2. Cat bites become infected more often than dog bites 3. Bartonella is a likely cause of the infection4. Pseudomonas is a likely cause of the infection DHS/PP
Microbiology of Infected Cat Bites From: Talan DA, et al. NEJM 1999;340:85-92. DHS/PP