Caracterização antigênica e molecular de amostras de rotavírus do tipo G1, obtidas de crianças participantes de estudos em gastroenterites virais, no período de 1982 a 2003, em Belém, Pará, Brasil

Abstract

Infant mortality remains an important problem of public health worldwide, mainly in developing countries. Of more than the 50 etiologic agents implied in this disease, rotavirus causes 111 million episodes of diarrhoea, resulting in more than 600,000 deaths among children less than five years, of which 82% are notified in the poorest countries of the world. This study aimed at the antigenic and molecular characterization of G1 rotavirus strains among children participanting of viral gastroenteritis studies, carried out from 1982 to 2003, in Belém, Pará, Brazil. One hundred and forty-eight specimens of G1 rotavirus were analyzed in the present investigation. Overall, the prevalence of the G1 type was of 41.3%, being that frequencies of this genotype through studies ranged from 11.0% to 67.6%. Eletropherotypes, G serotypes and P genotypes characterization of G1 rotavirus occurred in frequencies of 78.4%, 89.9% and 87.8%, respectively. Three long eletropherotypes varieties were identified, being that the L1 variety was found frequently (79.3%). The G1, G9 and G1+G4 serotypes were detected in 88.0%, 9.8% and 2.2% of the specimens, respectively. Mixed infection by G1+G4 genotype was detected in one sample. The prevalent binary combination was P[8],G1, being responsible for 72.3% of the cases. Mixed infections circulated in percentage of 20.0%, including genotypes P[4]+P[8],G1, P[6]+P[8],G1, P[4]+P[6],G1, P[4]+P[6]+P[8],G1 and P[6]+P[8],G1+G4. The G1 genotype circulated among 2nd to 35th months of age and a highest number of cases was registered between 6 to 16 months of age. Clinical severity differences among G1 and other genotypes of rotavirus were not verified. The present analysis gathers pioneer findings in Brazil, allowing to extend the knowledge concerning the antigenic and molecular diversity of the infections by G1 rotavirus and these results will allow to understand the genetic complexity of such viral agents.