Genótipos de rotavírus do grupo A de crianças com diarréia aguda atendidas em dois hospitais do município de Vitória ? ES, em período anterior à imunização para rotavirus
Group A rotaviruses (RVA) are a major cause of acute diarrhea in children up to 5 years in both developing and developed countries. The virion consists of 11 double-stranded RNA (dsRNA) genome enclosed in a triple-shelled capsid, which migration pattern in polyacrilamide gel eletrophoresis (PAGE) permit the classification in groups (A-G) and in long, short and super-short profiles. The outer shell is composed by VP4 and VP7 proteins which genes form the basis of the classification system in P and G genotypes, respectively. The knowledge about RVA genotypes distribution is essential for the establishment and the monitoring of preventive strategies. Considering the lack of these studies in Espírito Santo State, this investigation proposed: i) to determine RVA genotypes obtained from children withacute diarrhea, resident in Metropolitan region of Vitória - ES, from the Emergency Room at Hospital Infantil Nossa Senhora da Glória (HINSG) (80/253), collected between February2003 and June 2004 and; ii) to determine the frequency and RVA genotypes in children attended at Emergency (n=5) or hospitalized (n=63) from Pediatric Setor of CIAS/UNIMEDhospital, between July 2004 and November 2006. dsRNA were extracted from fecal suspensions by guanidine-silica procedure. PAGE was performed in CIAS/UNIMED samplesfor rotaviruses detection and eletropherotype determination. Complementary DNA was obtained by reverse transcription with pdN6 TM random primer. PCR were done with a pair ofconsensus primers for VP4 (4con2/4con3) or VP7 (9con1/9con2) and the products were submitted to Multiplex semi-nested PCR with specific primers for the G and P types (G1-G5, G9, P, P, P, P). RVA genotypes observed from HINSG were G1P (83.6%), G9P (7.5%), G1P (2.5%), G1 (1.3%), G4P (1.3%) and G?P (3.8%). Among samples stools from CIAS/UNIMED, 20.6% (14/68) were RVA positive, four and ten with short and long eletropherotypes, respectively. The following genotypes were observed: G9P (50%), G2P (28.7%), G2P, G1P and G?P (7%, each). No mixed infection was observed in both hospitals. These data reveal: i) G1P and G9P were the most common genotypes from HISNG and CIAS/UNIMED, respectively; ii) G9P was detected in the end of the samples obtainment, suggesting temporal fluctuation on genotype circulation; iii) G2P was found only in 2006 from hospitalized children. The results suggest that RotarixTM vaccine used in Brazil may efficiently reduce the severity and the number of RVA cases in the region studied. However, it must be emphasize the emergence of G2 type for which the vaccine shows lower protection, reforcing the need of continuous surveillance of RVA genotypes as vaccine efficacy monitoring.
Advisor:José Paulo Gagliardi Leite; Elenice Moreira Lemos; Liliana Cruz Spano
School:Universidade Federal do Espírito Santo
Source Type:Master's Thesis
Date of Publication:09/17/2007