Rotavirus infections in a special-care baby unit

Faeces were examined from one hundred and nine babies, i.e. about a quarter of the annual total, admitted to a special care unit. Thirty-five aged one to 33 days were found to be excreting rotavirus. Of these, 17 had diarrhoea, seven had loose stools and ii were symptomless. There were 41 episodes of diarrhoea in the 109 babies during the study with evidence of rotavirus infection in 59 per cent; no other enteric pathogen was found. Nosocomial infection was evident in five babies whose faeces were first found rotavirus-negative, but later positive. The unit was ‘screened’ on five occasions during the year of this study; up to 41 per cent of the babies were found to be excreting rotavirus. Nine infected infants were examined for their serological response. Two, examined by immunofluorescence, had antibody at less than their mothers' titres; a third, examined 11 days after the onset, had a titre identical to its mother's and a fourth, at 14 days after onset, had no detectable antibody. No specific neutralising activity against three rotavirus serotypes could be shown with the sera from those four babies. Specific IgM was sought in samples from two of the four, but none was found. The remaining five babies, only examined three to five months post-infection, were found to have no detectable antibody by immunofluorescence.