spotted fever group typhus group Ehrlichia group Q fever R. rickettsii R prowazekii E chaffeensis Q fever (Rocky Mountain (louseborne [human monocytotropic(Coxiella spotted fever) or epidemic ehrlichiosis(HME) Burneti typhus and Brill-Zinsser disease) R. Conorii R. Typhi Anaplasma (Boutonneuse fever)(murine typhus) phagocytophilum [human granulocytotropic anaplasma(HGa)] R australis Orienta pathogens E ewingii (Queensland tick tsutsugamushi typhus) (scrub typhus) R. Sibirica E. muris (North Asian tick typhus) R. akari Neorickettsia (rickettsial pox) sennetsu
spotted fever group typhus group Ehrlichia group Q fever R. rickettsii (Rocky Mountain spotted fever) R. prowazekii (louseborne or epidemic typhus and Brill–Zinsser disease) E. chaffeensis [human monocytotropic ehrlichiosis (HME)] Q fever (Coxiella Burnetii) R. Conorii (Boutonneuse fever) R. Typhi (murine typhus) Anaplasma phagocytophilum [human granulocytotropic anaplasma (HGA)] R. australis (Queensland tick typhus) Orienta tsutsugamushi (scrub typhus) pathogens E. ewingii R. Sibirica (North Asian tick typhus) E. muris R. akari (rickettsial pox) Neorickettsia sennetsu
Rocky Mountain spotted fever a气, a Most severe disease in the spotted fever group Motality 22% in untreated Motality 6% with treatment a occurs throughout the United States Mexico, and Central and South america late spring and summer a Dog tick or wood tick
Rocky Mountain spotted fever Most severe disease in the spotted fever group Motality 22% in untreated Motality 6% with treatment. occurs throughout the United States, Mexico,and Central and South America late spring and summer Dog tick or wood tick
FIGURE 5. Average reported annual incidence*of Rocky Mountain spotted fever, by state- United States, 1997-2002 口0口 0.1-1.0 11-49 5.099 口210 Per 1,000,000 persons per year
FIGURE 12. Comparison of ixodes scapularis(blacklegged tick), Amblyomma americanum (lone star tick), and Dermacentor variabilis(American dog tick), by life stage Blacklegged Tick (Ixodes scapularis) adult nymph lari Lone Star Tick(Amblyomma americanum) Dog Tick(Dermacentor variabilis) 森憲 Photo/GDG Ticks are shown in relative size to each other and to a dime
Pathogenesis Injected into the skin by ticks Proliferates in the skin disseminates via the bloodstream a Survives in the host cell cytoplasm spreads cell-to-cell producing necrotic cells hemorrhage in heart, lung, CNS, skin, intestine, pancreas, liver, skeletal muscle, and kidneys
Pathogenesis Injected into the skin by ticks Proliferates in the skin, disseminates via the bloodstream. Survives in the host cell cytoplasm spreads cell-to–cell producing necrotic cells hemorrhage in heart, lung, CNS, skin, intestine, pancreas,liver, skeletal muscle, and kidneys