Molecular analysis of rubella virus in travelers suspected of measles infection in São Paulo, Brazil

Abstract

Objective: To identify measles virus genotypes in three cases of travelers suspected of measles infection.

Methods: Samples (blood and urine) were collected for serology, virus isolation, and genotyping. Sera were analyzed for IgM antibodies against measles virus and rubella virus by enzyme-linked immunosorbent assay (ELISA) (Siemens - Marburg, Germany). Clinical samples (lymphocytes and urine) were inoculated into Statens Serum Institute rabbit corneal epithelial cell line- ATCC CL 60 (SIRC) and Vero Slam cells. RNA was extracted from clinical samples and cell culture was inoculated and processed by polymerase chain reaction (PCR) with oligonucleotides specific for measles virus (MV) and rubella virus (RV).

Results: All patients showed IgM negative serology for MV and positive IgM for RV. RV belonging to genotypes 1B, 1C, and 1E were isolated from patients who came from Finland, Peru, and Germany, respectively. Genotype 1B has been found in Europe and on the East Coast of South America; 1C has been found in Peru and the West Coast of South America, and 1E, first identified in 1997, now appears to have worldwide distribution.

Conclusion: Information about RV and MV genotypes circulating in São Paulo is essential for the control of measles, rubella, and congenital rubella syndrome (CRS) in Brazil.