Rotavirus gastroenteritis and asymptomatic infections in community child care centres

Abstract

Background to the study: The inception of this study occurred at a time when tetravalent rhesus reassortant rotavirus vaccine was about to be licensed in the USA, and data were needed to determine the potential importance of such a vaccine in the UK community. There were already established systems in place for monitoring the prevalence of rotavirus in children presenting to hospitals with gastroenteritis. These systems, largely operated by the Public Health Laboratory Service (PHLS, now Health Protection Agency [HPA]), also provided information about the rotavirus serotypes causing moderate to severe disease. Much less was known regarding the community rate of rotavirus infection in young children. There was a general belief, validated by a subsequent prospective community based IID study, that many cases of diarrhoea were mild, and did not reach the notice of primary health care providers, let alone provide samples for the laboratory surveillance network that characterised rotavirus serotypes. Before a vaccine can be introduced into a community, detailed data regarding its potential health and economic benefits are required. For rotavirus in the UK, estimates of the health impact of only severe disease were available. The rotavirus serotypes causing this disease were also available, with serotypes G1-G4 causing 95% of disease. Little was known about the economic impact of rotavirus, apart from direct hospital costs for moderate to severe disease estimating in 1994 a cost of £6.3 million per annum for England and Wales. There were little or no data regarding: (i) the rate of mild community acquired diarrhoea, although this was addressed subsequently in the IID study; (ii) the family impact of rotavirus disease; (iii) the economic impact of rotavirus gastroenteritis not presenting to hospital; (iv) rates of disease in potential high-risk groups who may benefit from a targeted vaccine approach; (v) the rotavirus serotypes causing mild disease. The stated aims of this study were to: (1) Determine the incidence, aetiology, and cost implications of diarrhoeal disease in day care centres. (2) Assess the sensitivity of rotavirus RT-PCR in the diagnosis of rotavirus diarrhoea compared to standard diagnostic techniques. (3) Document rotavirus serotype epidemiology in symptomatic and asymptomatic community infections in young children in nurseries.