肥达氏试验为诊断伤寒,副伤寒的常规试验方法.但近年来有人提出本法缺乏特异性,某些疾病有假阳性反应,且阳性率不高,甚至提出淘汰这一试验方法.因此,全面认识和评价肥达氏反应的意义显得很有必要.一、肥达氏试验的基本原理:用已知的伤寒杆菌“H”和“O”菌液及副伤寒(?)乙、丙的“H”菌液作为抗原,与病人的血清(?)细菌凝集反应,来测定病人血液中各种抗体的凝集效价,以诊断伤寒及副伤寒.二、肥达氏试验的阳性标准和抗体出现及所维持的时间:肥达氏试验的阳性标准,一般以“O”1:80及“H”1:160以上,甲、乙、丙各1:40以上为阳 Wadda’s test is a routine test for the diagnosis of typhoid and paratyphoid fever, but in recent years it has been suggested that this law lacks specificity and that some diseases have false-positive reactions and the positive rate is not high, It is necessary to fully understand and evaluate the significance of Widal reaction.First, the basic principle of Widal’s test: Using the known bacteriophages of “H” and “O” and typhoid (“ Second, the positive standard of Wadalaf’s test and the antibody can be used to diagnose the agglutination titer of various antibodies in the blood of the patient. Occurrence and maintenance of time: Wadda’s test positive standards, generally ”O“ 1:80 and ”H" 1: 160 above, A, B, C each of more than 1:40 yang