Genetic variation of varicella-zoster virus strains circulating in Mexico City
Received 9 July 2009; received in revised form 1 September 2009; accepted 4 September 2009. published online 15 October 2009.
Abstract
Background
Different studies regarding VZV genotype distribution worldwide have demonstrated that genetic diversity and epidemiology of infection significantly vary from region to region. In Mexico, VZV genotype distribution is largely unknown mostly due to the lack of a surveillance system that monitors accurately the presence of viral strains circulating in the country.
Objective
To identify the main VZV genotypes circulating in the metropolitan area of Mexico City.
Study design
In this study, 127 different VZV isolates, obtained from residents of the Mexico City Metropolitan area from 2005 to 2008, were identified and genotyped. Viral detection and preliminary genotyping was performed by amplification of the VZV ORF-38 and -54 and RFLP analysis using PstI and BglI endonuclease restriction patterns, respectively. Genotype was confirmed by nucleotide sequence variation along the ORF-22.
Results
RFLP analysis classified 121 viral strains as European and 6 as mosaic genotype. Genotyping scheme based on the ORF-22 sequence variation identified 120 viral strains belonging to the E genotype, 6 M1 and 1 M4 genotype strains.
Conclusions
VZV European genotype appears to predominate in Mexico City. This is the first study addressing VZV genotype distribution in Mexico. The information reported in this paper may be useful for future epidemiological studies conducted in the country and also contributes to understand better the molecular epidemiology of VZV in the Americas.
aDepartamento de Investigaciones Inmunológicas, Instituto de Diagnóstico y Referencia Epidemiológicos, Secretaría de Salud, Mexico City, Mexico
bDepartamento de Genoma de Patógenos, Instituto de Diagnóstico y Referencia Epidemiológicos, Secretaría de Salud, Mexico City, Mexico
Corresponding autor at: Departamento de Investigaciones Inmunológicas, Instituto de Diagnóstico y Referencia Epidemiológicos, Carpio 470, Mexico City 11340, Mexico. Tel.: +52 55 5342 7563; fax: +52 55 5341 3264.
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