Diagnosis is made by any blood, bone marrow or stool cultures and with the Widal test (demonstration of salmonella antibodies against antigens O-somatic and H-flagellar).
http://en.wikipedia.org/wiki/Typhoid_fever
Includes cause, symptoms, diagnosis, risk factors, prognosis, treatment, and prevention.
http://www.nlm.nih.gov/medlineplus/ency/article/001332.htm
Learn typhoid fever causes (Salmonella typhi in contaminated water), transmission, history, symptoms, diagnosis, treatment, prognosis and prevention (vaccine).
http://www.medicinenet.com/typhoid_fever/article.htm
The sensitivity of a single blood culture for the diagnosis of typhoid fever has been estimated as 50% when compared with bone marrow aspirate culture ...
http://www.cdc.gov/ncidod/eid/vol9no5/02-0428.htm