Typhoid can be confirmed by various investigations and each of them becomes positive at various times in the course of the disease. This can be remembered as, BASU.
- Blood culture in the 1st week (Bone marrow culture is better, but not commonly done)
- Antibody detection (Widal) in 2nd week
- Stool culture in the 3rd week
- Urine culture in the 4th week