Widal test Serum agglutinins(antibodies) rise sharply during the second and third weeks of salmonella typhi infection This test demonstrates the presence of somatic(O)and flagellar(H)agglutinins(antibodies) to Salmonella typhi in the patient's serum using suspensions ofO and H antigens Antigens of S paratyphi A, S paratyphi b,s paratyphi C are included in most commercial kits The result will be used as an indirect signal of the infection5 Serum agglutinins(antibodies) rise sharply during the second and third weeks of Salmonella Typhi infection This test demonstrates the presence of somatic (O) and flagellar (H) agglutinins(antibodies) to Salmonella typhi in the patient's serum using suspensions of O and H antigens. Antigens of S. paratyphi A, S. paratyphi B, S. paratyphi C are included in most commercial kits The result will be used as an indirect signal of the infection Widal test