Airborne, eg, in hay; animal reservoirs (stock animals, and cats, esp parturient ones). Tick vector from mouse reservoir; milk from chronically infected cows. Worldwide

Sx:Fever, headache, pains in muscles and chest wall; sudden onset

Si:

Cardiovascular: relative bradycardia, migratory thrombophlebitis

Skin: papule, then vesicle and eschar after 3-4 wk (rare)

Pulmonary: patchy pneumonitis, dry cough, pleurisy

GI: hepatitis

Rheumatoid: migratory arthritis

2-4 wk

Endocarditis (rare)

Lab:

Bact:Fastidious grower, needs high CO₂, low O₂

Serol:Comp-fix antibody elevated; use same antigens used to test for typhus, Weil-Felix negative (r/o rickettsial pox)

Rx:

Vaccine: none

of disease: tetracycline