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Arthropod Diseases Affecting Outdoor Activities: Lyme Disease. Dr. Richard M. Houseman Department of Entomology University of Missouri. Lyme Disease Background. Bacterial disease first identified in Conneticut (1977) Inflammation of joints (arthritis) Rarely, if ever fatal
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Arthropod Diseases Affecting Outdoor Activities: Lyme Disease Dr. Richard M. Houseman Department of Entomology University of Missouri
Lyme Disease Background • Bacterial disease first identified in Conneticut (1977) • Inflammation of joints (arthritis) • Rarely, if ever fatal • 92% 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) • Borrelia burgdorferi • Similar bacteria in Europe, Asia
Lyme Disease Transmission • Transmitted 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 seasonal • Most in late spring to mid summer (nymphs) • Few in fall and early spring (adults)
SPRING SUMMER FALL WINTER nymphs adults + eggs larvae adults YEAR 2 YEAR 1 adults nymphs nymphs (dormant) adults (dormant)
Lyme Disease Risks • Risk of exposure is greatest in woods and fringe areas of properties • Ticks may also be transported to lawn/garden • Highest attack rates • Children 0-14 and 30+ years of age • Outdoor recreation, outdoor work, new homes in wooded areas • Blood transfusions, infected blood, urine are NOT documented risks
Lyme Disease Symptoms • Within 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 months • Also swelling, meningitis, facial palsy, encephalitis • Antibiotic treatment for 3-4 weeks • Doxycycline, amoxicillin, erythromycin • NO immunity
Lyme Disease in Missouri • 90 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) • Southern Tick Associated Rash Illness
STARI • Southern Tick Associated Rash Illness • ER indistinguishable from Lyme Disease • Transmitted by bite of Amblyomma americanum • Tick is abundant in southern states • Similar life cycle and ecology • Borrelia lonestari • Serologically different from Lyme bacteria
Preventing Lyme Disease • Minimize and Avoid tick habitats • Leaf litter, brush, wood piles, tall grass • Spring/summer when nymphs are prevalent • Use personal protective measures • Clothing • Long sleeved shirts, light colors, tuck pants into socks • Permethrin • Repellents • DEET on clothing or skin • Tick check and removal