Recherches de la réaction agglutinante dans le sang et le sérum desséchés des typhiques et dans la sérosité des vesicatoires.

Developing the work of Gruber and Durham, Widal noted that a patient’s serum could be tested with bacteria of known type and his disease identified by this means. They demonstrated specific agglutinins in the blood of typhoid patients, making possible an agglutination reaction for the diagnosis of typhoid, the“Gruber-Widal test”.