Epidemiologia e caracterizaçao dos genótipos P (VP4) e G (VP7) de rotavirus grupo A humano no estado do Paraná, 2000-2003

Abstract

Resumo: Group A rotaviruses are the major etiological agents of viral acute gastroenteritis of infants and young children and constitutes an important cause of infantile mortality in developing countries. The previous knowledge of the epidemiologic aspects of the infection and the antigenic and molecular characteristics of rotavirus constitutes indispensable information for the success of behaviours of control and prophylaxis of this disease. The present work, of retrospective nature, had for objectives to evaluate epidemiological data of disease caused by rotavirus and to characterize the G (VP7) and P (VP4) genotypes of the human group A rotaviruses samples, identified in cases of acute diarrhea in Paraná State, Brazil. In the period of January/2000 to December/2003, 550 fecal samples from children and adults, with acute diarrhea, were sent for the diagnosis of group A rotavirus. By enzyme immunoassay 120 samples (21.8%) were positive to group A rotaviruses. These, 114 samples were genotyped by multiplex-nested-PCR. The higher frequency (77.5%) of positive samples (n=93) was observed in children under 5 years old. In the cold and dry seasons of the four evaluated years was observed the greatest rate of rotavirus positive cases. The genotypes of major occurrence were: G1 (50.9%), G4 (9.6%), G9 (7.0%), G2 (1.7%), G3 (0.9%), P[8] (71.9%), P[4] (3.5%). The main combinations found to P and G genotypes were: P[8],G1 (46.5%) and P[8],G4 (9.6%). Mixed infections, characterized by rotaviruses with more than one G, and/or P genotypes, and nontypeable rotavirus were observed, respectively, in 8.8%, 3.5% and 16.7% of samples. The identification of G9 genotype in rotavirus samples evaluated along four years of studies ratifies the emergency of this genotype also in Paraná State, as worldwide