Typhoid Antibodies (Widal) Test

A serological test (such as the Widal test or more recent tests) is used to detect the presence and titer of antibodies (agglomerates) in blood serum against the somatic (O) and ciliary (H) antigens of typhoid-causing Salmonella and paratyphoid-causing Salmonella A, B, and C. This supports the clinical diagnosis of typhoid fever.