Rotavirus genotypes circulating in Brazil before national rotavirus vaccination: A review

Background: Rotavirus vaccine was recently introduced in Brazil, which has the potential to greatly reduce childhood deaths from diarrhoea. To provide baseline data to assess the effect of mass rotavirus vaccination on the ecology of circulating rotavirus strains, we systematically analysed published studies in the pre-vaccine era. Aims: To describe the distribution of rotavirus genotypes in Brazil prior to vaccine introduction. Methods: Systematic literature searches in health-related databases from 1986 to 2006. Information extracted and analysed by time and region. Results: 117 studies with 48,401 participants were included. Of these, 3036 were infected with rotavirus. More than 51 genotype combinations were reported, the distribution of which changed over time.P[8]G1 (43%) was the most frequent genotype throughout, followed by P[8]G9 (22%) and P[4]G2 (7%). The detection rate of P[8]G9 increased, while P[4]G2 decreased during the study period. There was a high frequency of GIP combinations between 1995 and 2000 and a low frequency before and after these years. Conclusions: While considerable diversity of rotavirus strains was recognized during the pre-vaccine era, three strains comprised 72% of the total analysed. These data provide a baseline against which any changes in circulating rotavirus strains post-vaccine introduction can be measured. 0 2008 Elsevier B.V. All rights reserved.