Person-to-person spread of Salmonella typhimurium after a hospital common-source outbreak

In September, 1973, diarrhoea caused by Salmonella typhimurium developed in 32 people in a Maine hospital. Both epidemiological and microbiological evidence indicated that raw egg beaten in milk ("egg-nog") was responsible for the infection. However, 6 patients and 8 employees had not had egg-nog, and their illness developed after the source of infection had been recognised and removed. Most of these people had had direct contact with an infected patient, and presumably acquired the infection by person-to-person spread. It is concluded that person-to-person spread of S. typhimurium can occur in hospitals and can be a hazard to patients and staff.