Genomic characterization of wild-type measles viruses that circulated in different states in Brazil during the 1997 measles epidemic.

Despite the marked reduction in the incidence of measles in Brazil, a measles epidemic occurred in this country in 1997. The measles cases observed during this epidemic began to reappear in large numbers in São Paulo, and spread to Rio de Janeiro and other Brazilian states. In the present study molecular biology techniques were used for the detection and genomic characterization of measles viruses from clinical samples such as urine and nasopharyngeal secretions collected in the states of Rio de Janeiro, Minas Gerais and Paraná, during the 1997 epidemic. RT-PCR and nucleotide sequence analysis of part of the carboxyl-terminal region of the nucleoprotein gene of measles viruses obtained directly from clinical samples or from infected cell cultures during this epidemic classified all as wild-type of genotype D6. As the genotype D6 was identified in different Brazilian states, this study demonstrated that this genotype was circulating in Brazil during the 1997 epidemic.