serological test is the difference between widal test and typhidot test.
what is the difference between widal test and typhidot test?
serological test
diagnosis is made by any blood, bone marrow, or stool cultures and with the widal test (demonstration of antibodies against "salmonella" antigens o-somatic and h-flagellar). in epidemics and less wealthy countries, after excluding malaria, dysentery, or pneumonia, a therapeutic trial time with chloramphenicol is generally undertaken while awaiting the results of the widal test and cultures of the blood and stool.





















































the widal test is time-consuming and prone to significant false positive results. the test may also be falsely negative in the early course of illness. however, unlike the typhidot test, the widal test quantifies the specimen with titres.
typhoid fever
the widal test is positive if to antigen titer is more than 1:160 in an active infection, or if th antigen titer is more than 1:160 in past infection or in immunized persons. a single widal test is of little clinical relevance due to the high number of cross-reacting infections, including malaria. if no other tests (either bacteriologic culture or more specific serology) are available, a fourfold increase in the titer (e.g., from 1:40 to 1:640) in the course of the infection, or a conversion from an igm reaction to an igg reaction of at least the same titer, would be consistent with a typhoid infection.
widal test