[Sharp increase of infections with Salmonella serotype Typhimurium DT104 in The Netherlands].

Salmonella remains an important source of food-related outbreaks of gastro-enteritis. In The Netherlands, regional laboratories send cultured Salmonella isolates to the National Institute of Public Health and the Environment (RIVM) for sero- and phage typing. Abnormal increases in the incidence of Salmonella infections are monitored by means of surveillance. Since the middle of September 2005, there has been a sharp increase in Salmonella Typhimurium DT104 (Dutch phage type 506 and 401) isolates, from all parts of the country and mainly from 6- to 20-year-olds. Since a first series of telephone interviews did not yield a clear source of the outbreak, a more extensive, written study has been started in a larger group of patients and corresponding controls.