In the third week toxaemia increases and the patient may pass into coma and die. The atypical presentation of typhoid makes it difficult to be diagnosed. Bone and joint infection is seen, especially in children with sickle-cell disease. In the first week the diagnosis may be difficult because in this invasive stage with bacteraemia the symptoms are those of a generalised infection without localising features. A white blood count may be helpful as there is typically a leucopenia.
Blood culture is the most important diagnostic method in a suspected case.
The faeces will contain the organism more frequently during the second and third weeks. The Widal reaction detects antibodies to the causative organisms and is helpful in the diagnosis of the disease in the second week of illness and afterwards. However, it is not a reliable diagnostic test and should be interpreted with caution. Ciprofloxacin in a dose of 500 mg 12-hourly is the drug of choice. Treatment should be continued for 14 days.