1. Arthropod Diseases Affecting Outdoor Activities: Lyme Disease Dr. Richard M. Houseman Department of Entomology University of Missouri

2. Lyme Disease Background Bacterial disease first identified in Conneticut (1977)Bacterial disease first identified in Conneticut (1977) –Inflammation of joints (arthritis) –Rarely, if ever fatal 92% of all cases occur in nine states92% of all cases occur in nine states –CT, RI, NY, PA, DE, NJ, MD, MA, WI. Leading cause of vector-borne infectious disease in U.S. (15,000 cases annually)Leading cause of vector-borne infectious disease in U.S. (15,000 cases annually) –Borrelia burgdorferi –Similar bacteria in Europe, Asia

5. Lyme Disease Transmission Transmitted by the bite of infected tick Ixodes scapularisTransmitted by the bite of infected tick Ixodes scapularis –Rodents, deer, birds, dogs are primary hosts –Human infections after tick feeds for >36 hours In temperate areas (24º-66º latitude) virus transmission is seasonalIn temperate areas (24º-66º latitude) virus transmission is seasonal –Most in late spring to mid summer (nymphs) –Few in fall and early spring (adults)

8. YEAR 1 YEAR 2 adults + eggs larvae nymphs (dormant) nymphs adults (dormant) SPRING SUMMER FALL WINTER

9. Lyme Disease Risks Risk of exposure is greatest in woods and fringe areas of propertiesRisk of exposure is greatest in woods and fringe areas of properties –Ticks may also be transported to lawn/garden Highest attack ratesHighest attack rates –Children 0-14 and 30+ years of age Outdoor recreation, outdoor work, new homes in wooded areasOutdoor recreation, outdoor work, new homes in wooded areas Blood transfusions, infected blood, urine are NOT documented risksBlood transfusions, infected blood, urine are NOT documented risks

11. Lyme Disease Symptoms Within 7-14 days 80% of people develop red, expanding bulls eyeWithin 7-14 days 80% of people develop red, expanding bulls eye –Tired, fever, headache, muscle aches, joint pain If untreated some patients develop arthritis within a few weeks to monthsIf untreated some patients develop arthritis within a few weeks to months –Also swelling, meningitis, facial palsy, encephalitis Antibiotic treatment for 3-4 weeksAntibiotic treatment for 3-4 weeks –Doxycycline, amoxicillin, erythromycin –NO immunity

13. Lyme Disease in Missouri 90 to 100 cases per year on average90 to 100 cases per year on average –Low risk overall –Relatively high compared to neighboring states –Reported cases have decreased dramatically in recent years Lyme-like condition present (STARI)Lyme-like condition present (STARI) –Southern Tick Associated Rash Illness

16. STARI Southern Tick Associated Rash IllnessSouthern Tick Associated Rash Illness –ER indistinguishable from Lyme Disease Transmitted by bite of Amblyomma americanumTransmitted by bite of Amblyomma americanum –Tick is abundant in southern states –Similar life cycle and ecology Borrelia lonestariBorrelia lonestari –Serologically different from Lyme bacteria

18. Preventing Lyme Disease Minimize and Avoid tick habitatsMinimize and Avoid tick habitats –Leaf litter, brush, wood piles, tall grass –Spring/summer when nymphs are prevalent Use personal protective measuresUse personal protective measures –Clothing Long sleeved shirts, light colors, tuck pants into socksLong sleeved shirts, light colors, tuck pants into socks PermethrinPermethrin –Repellents DEET on clothing or skinDEET on clothing or skin –Tick check and removal