An outbreak of diarrhoeal disease in a modern mother-and-child health clinic prompted the health authorities to initiate a retrospective cohort study in order to assess the scope of the outbreak and to identify possible risk factors. The management of the clinic had been rather concerned because four similar outbreaks had occurred during the last two years.
A total of 151 guests, i. e. mothers with their children, who had arrived some days before the peak of the outbreak for a three-weeks-stay and another 15 guests who had arrived earlier and had extended their stay were enrolled in the study which mainly focused on the possible role of treatment measures as risk factors. In addition, a total of 49 staff members were requested to provide information about symptoms, working area and attendance at work.
Relevant data were available from 164 of 166 guests and 47 of 49 staff members (response rates 98.8 % and 96.0 % , respectively). The attack rate among guests was 44.0 % (adults 27.0 % , children 54.0 % ) and among staff 23.4 % . The mean age of affected children (3.5 years) was significantly lower than that of those not affected (6.3 years). The main symptoms were diarrhoea and vomiting. The sudden start of the outbreak suggested a single source of infection which, however, remained unknown. Person-to-person transmission was supposed to be the cause of the following spread. No association between distinct treatment measures and the disease was proven by the cohort study.
Norwalk-like viruses as well as astroviruses were detected by polymerase chain reaction in specimens taken from seven patients. No other enteropathogenic agents were found.
Regarding the special conditions in a mother-and-child health clinic where social contacts among guests are much more frequent and intensive than among patients in a “normal” hospital, measures to prevent the spread of gastrointestinal infections should concentrate on early recognition and isolation of symptomatic individuals. Guests and staff members should be instructed to keep to the rules of personal hygiene, especially handwashing. If disinfection is required, it should be virucidal.
