“…Nevertheless, they suggested that ampicillin was probably more effective than chloramphenicol in the treatment of carriers. In other reports, the results of treatment of salmonellosis and Salmonella carriers with ampicillin have been variable (Stewart, Coles, Nixon & Holt, 1961;Trafford, Maclaren, Lillicrap, Barnes, Houston & Knox, 1962;Ross, Lovrien, Zaremba, Bourgeois & Puig, 1962;Pettersson, 1964), and failure was often associated with gall-bladder disease and stones (Tynes & Utz, 1962;Bullock, 1963). The apparent discrepancy between the in vitro activity of ampicillin and the results of treatment is often difficult to explain.…”