In Vitro Activities of Telithromycin (HMR 3647) against Rickettsia rickettsii , Rickettsia conorii , Rickettsia africae , Rickettsia typhi , Rickettsia prowazekii , Coxiella burnetii , Bartonella henselae , Bartonella quintana , Bartonella bacilliformis , and Ehrlichia chaffeensis