The investigators will also evaluate several newly available, rapid "dipstick" tests for the diagnosis of plague using serum, bubo aspirate, sputum, and urine specimens that will have already been collected from the patients enrolled in the drug trial. These rapid tests have been developed by several American companies and the Institut Pasteur in Madagascar, and have not been fully evaluated for use with human specimens. These results will be compared to standard diagnostic techniques. Such rapid diagnostic tests will be useful for plague diagnosis in developing nations and during bioterrorism events.