Abraham G, Teklu B, Gedebu M, Selassie G H, Azene G
Trop Geogr Med. 1981 Dec;33(4):329-33.
The usefulness of a single Widal test to diagnose typhoid fever in Ethiopia was investigated in three study groups both retrospectively and prospectively. These were blood culture proven typhoid and non-typhoid patients and healthy individuals. Salmonella typhi H and O titres greater than or equal to 1:160 occurred in respectively 82% and 58% of typhoid fever patients; only 4% of healthy individuals and 8% of non-typhoid patients had Widal titres greater than or equal to 1:80. In typhoid fever, the H titre is elevated earlier and more frequently than the O titre. Antibody rise is maximal during the second week of illness. Antibiotic treatment did not affect the rise of antibody titre in typhoid fever. A single Widal test in an unvaccinated Ethiopian patient showing H and/or O titres greater than or equal to 1:160 and typhoid-like symptoms is strongly suggestive of typhoid fever. It also appears that H titre is more useful than O titre. More false positives are found than false negatives. Under these circumstances, the clinical picture is the decisive factor in making a diagnosis of typhoid.
在三个研究组中，对单一维达试验在埃塞俄比亚诊断伤寒热的效用进行了回顾性和前瞻性研究。研究对象包括血培养确诊的伤寒患者、非伤寒患者以及健康个体。伤寒热患者中，伤寒杆菌H和O效价大于或等于1:160的分别占82%和58%；只有4%的健康个体和8%的非伤寒患者维达效价大于或等于1:80。在伤寒热中，H效价比O效价升高得更早且更频繁。抗体在发病第二周上升幅度最大。抗生素治疗不影响伤寒热患者抗体效价的上升。在未接种疫苗的埃塞俄比亚患者中，单次维达试验显示H和/或O效价大于或等于1:160且有伤寒样症状，强烈提示为伤寒热。似乎H效价比O效价更有用。假阳性比假阴性更多。在这种情况下，临床表现是诊断伤寒的决定性因素。
