“…As far as can be discovered from a survey of the literature, studies on hospital cross-infections have been concerned mainly with the spread of haemolytic streptococci (Allison & Brown, 1937;Cruickshank & Godber, 1939), diphtheria bacilli (Glass & Wright, 1938; Crosbie & Wright, 1941) and other upper respiratory tract pathogens. However, the spread of gastro-intestinal infections has not been subjected to intensive study mainly because of the frequent difficulty in establishing the aetiology in many of these outbreaks (Rice, Best, Frant & Abramson, 1937; Crowley, Downie, Fulton & Wilson, 1941). In the present instance we were fortunate in dealing with Salmonlla derby, a pathogen of apparent rarity in Australia.…”