应用聚合酶链反应（ＰＣＲ）扩增伤寒沙门氏菌鞭毛抗原基因Ⅵ区一段特异性的ＤＮＡ片断，再用地高辛标记探针与之杂交检测，并用非伤寒沙门氏菌作对照，结果仅伤寒沙门氏菌阳性。实验表明，当标本中伤寒沙门氏菌含量达１０ｃｆｕ／ｍｌ时，即可检出。在伤寒发病早期，当机体抗体水平尚处于低水平时，应用ＰＣＲ斑点杂交检测伤寒沙门氏菌可提高伤寒的诊断率；在伤寒病程后期，应用ＰＣＲ斑点杂交检测治疗后带菌状态具有重要价值。 Polymerase chain reaction (PCR) amplification of Salmonella typhi flagella antigen Ⅵ region a specific DNA fragment, and then detected by digoxigenin-labeled probe with non-typhoid Salmonella control, the results were only Salmonella typhi positive. Experiments show that when the specimen of Salmonella typhi content of 10cfu / ml, you can detect. In the early stage of typhoid fever, the detection of Salmonella typhimurium by PCR-Dot blot hybridization can improve the diagnosis rate of typhoid fever when the level of antibody is still low. In the late stage of typhoid fever, it is of great value to detect the bacteriological status by PCR-dot blot hybridization.