<prompt> In initial stages of typhoid, salmonella can be detected in:FaecesUrineBloodAll of the above  <response>: Blood culture: Blood culture is a very useful procedure for diagnosis of enteric fever. It is positive in approximately 90 of cases in the first week of fever, 75 of cases in the second week, 60 in the third week, and 25 thereafter till the subsidence of pyrexia. Blood cultures, however, rapidly become negative on treatment with antibiotics.Parija SC. Textbook of Microbiology Immunology. Elsevier Health Sciences; 2014. Page: 277 