we have studied for 1-year period a group of 144 children ( 31 newborn infants , 62 aged 1 year and 51 aged 2 years ) who were randomly selected from the registrar 's office of sevilla with the purpose of determining the incidence of diarrhoea and the prevalence of enteropathogenic microorganisms .
C0008059
children
C0021289
newborn infants