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

Abstract

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.

Genetic Analysis of Measles Viruses Isolated in the United States between 1989 and 2001: Absence of an Endemic Genotype since 1994

“…However, the widespread distribution of D3 viruses with a low level of nucleotide variability suggests that during the resurgence period, the epidemiological conditions favored rapid spread of virus along a limited number of chains of transmission. A similar pattern of spread was observed for a very large outbreak of measles that occurred in São Paulo, Brazil, during 1997 that subsequently led to smaller outbreaks in other areas of South America [22][23][24][25][26]. In this case, nearly identical genotype D6 sequences were obtained in São Paulo and from the other South American outbreaks.…”

Molecular Epidemiology of Measles Viruses in the United States, 1997–2001

“…During 1997–2001, genotype D6 viruses were imported into the United States from Italy, Greece, Ukraine, Croatia, Cyprus, and the United Kingdom. During 1997, viruses from genotype D6 were imported into the United States from the large measles outbreak that occurred in São Paulo, Brazil, and spread to other South American countries (29–33). The viruses that were isolated from cases imported from Brazil to Minnesota (MN33-97) and Pennsylvania (PA28-97) during 1997 had sequences identical to those obtained from measles viruses isolated during the outbreak in Brazil.…”

Genetic Homogeneity of Measles Viruses Associated with a Measles Outbreak, São Paulo, Brazil, 1997

“…Although virologic surveillance was certainly incomplete, some information is available about measles genotypes present in Brazil before the 1997 outbreak in São Paulo. Genotype D5 was detected in a sporadic case in São Paulo in 1995 and in sporadic cases that occurred in the state of Bahia in 1996 (21). Genotype D5 viruses that circulate in Japan have been associated with importation of viruses from Japan into other countries (26,32,33).…”

“…The source of the genotype D5 viruses detected in São Paulo and Bahia was not identified. Genotype C2 viruses were detected in a small outbreak in the state of Santa Catarina in 1996 (21). C2, another indigenous genotype in Europe, is often associated with imported cases in other parts of the world (27–31).…”