An outbreak of Salmonella urbana infection in neonatal nurseries

An outbreak of neonatal infection with Salmonella urbana in three neonatal wards of a teaching hospital in Bangkok, Thailand is described. The outbreak lasted for 5 days. Fifty-seven neonates had gastrointestinal infection, 37 had diarrhoea, and three had bacteraemia. The attack rates were 43% for infection, 29% for diarrhoea, and 2.3% for bacteraemia. Epidemiological evaluation suggested that a contaminated wash basin in the labour nursery was the source of infection. Delay in controlling this outbreak occurred because the staff assumed that person-to-person transmission was the mode of spread, thus ignoring epidemiological data that would have led to the identification of the source of infection.