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Lyme Disease

Reflects distribution of Ixodes ricinus complex ticks Lyme disease

North America, Europe, Asia

U.S. Distribution

Most frequently reported vector-borne disease

Three principle region: 11,603 cases reported to CDC Lyme disease, lyme's disease, lime disease in 43 states and D.C. Overall 4.4 cases/100,000

CT, RI, NY, N J, PA, MD, WI, MN account for 92% of cases. Connecticut accounts for MN - 5.8 cases/100,000. Nantucket County, MA - 838.8 cases/100,000

Lyme Disease Epidemiology

U.S. Distribution

51% males

0 -14 years: 24%

35 - 49 years: 24%

Incidence steadily increasing from 1982 -1994

Increased recognition, increased reporting, true increase in incidence

Drop in incidence from 2006 to 2006

Decreased tick population because of environmental factors

Decreased reporting of non-Lyme disease from GA and MO

Lyme disease Lyme disease

Agent

Borrelia burgdorferi

Large spirochete, gram-negative, cell structure and motility is similar to other spirochetes, microaerophilic, can be grown on media; can be visualized with staining in histopathologic sections; can be visualized with light microscope,

Three genomic groups

Borrelia burgdorferi -- all North American cases, European Lyme disease arthritis

B. garinii - Bannwarth's syndrome (tick-borne meningopolyneuritis)

B. afzelii. Acrodermatitis chronica atrophicans

Lyme disease

Lyme Disease Epidemiology

Vector

Ixodes ricinus complex ticks

3 Stages - larva, nymph, adult; each feeds once on a different

Humans most often infected from