Affiliation: | 1. Molecular Microbiology Laboratory, National Institute of Pediatrics, Mexico City, Mexico;2. Department of Pediatric Infectious Diseases, National Institute of Pediatrics, Mexico City, Mexico;3. Bacteriology Laboratory, National Institute of Pediatrics, Mexico City, Mexico;4. Department of Epidemiology, National Institute of Pediatrics, Mexico City, Mexico;5. Department of Research Methodology, Instituto Nacional de Pediatría, Mexico City, Mexico |