Incidence of nosocomial rotavirus infections, symptomatic and asymptomatic, in breast-fed and non-breast-fed infants

Rotavirus is one of the most important aetiological agents of nosocomial infections in childhood. We studied the incidence of nosocomial rotavirus infections in 420 patients (age range 1-18 months) consecutively admitted from 1 December 1999 to 31 May 2000 to the infant ward of the Department of Paediatrics, University of Turin. We also evaluated the protective effect of breast feeding. Faecal specimens were collected from every child (whether developing diarrhoeic symptoms or not) and tested for rotavirus during hospitalization and 72 h after discharge. The incidence of rotavirus nosocomial infections was 27.7%. The incidence of symptomatic nosocomial infections was 16.8%, and the incidence of asymptomatic infections was 10.9%. The attack rate of the infections that occurred during hospitalization was 11.8%, while for those occurring after discharge, it was 15.9%. Rotavirus infection, on average, prolonged hospital stay from 5.2 to 6.4 days. 10.6% of breast-fed infants and 32.4% of non-breast-fed infants contracted rotavirus infection (P<0.005). None of the breast-fed infants who contracted rotavirus infection developed diarrhoeic symptoms.