The Widal test measures the capacity of antibodies against LPS and flagella in the serum

of individuals with suspected typhoid fever to agglutinate cells of S. Typhi; the test was

introduced over a century ago and it is still widely used [20]. It is simple, inexpensive, and

takes only a few minutes.In case of singular Widal test, baseline values for the normal range

was found to be 1:20 - 1:80 for all the antigens (TO, TH, AO, AH, BO, BH), except BH, for

which it was 1:20-1:40.