title: Prevalence of pneumococcal disease, serotype distribution, and antimicrobial susceptibility in Mexican children younger than 5 years of age.
abstract: OBJECTIVE
  Streptococcus pneumoniae constitutes one of the main causes of sepsis, bacteremia and meningitis (pneumococcal invasive disease - PID), and pneumonia in infants and small children. Antipneumococcal vaccination in Mexico is expected to be a useful strategy to reduce morbimortality due to this cause. We undertook this study to determine the prevalence of PID and pneumonia and the PCV vaccination status of affected children as well as serotype distribution and antimicrobial susceptibility of pneumococcal strains responsible for PID in infants and small children in Mexico.
  
  
  METHODS
  From March 2010-June 2011, a prospective multicenter study was carried out in four states in Mexico to determine the prevalence of bacteremia, meningitis, septic arthritis and pneumonia due to S. pneumoniae and other microorganisms in children from 28 days-59 months of age. Isolated pneumococcal strains were serotyped and their antimicrobial resistance determined.
  
  
  RESULTS
  During the study period, 545 children were diagnosed with bacteremia, meningitis, septic arthritis or pneumonia; 46.7% of these clinical entities occurred among children <12 months of age. Community-acquired pneumonia was the most prevalent disease. It was possible to identify a causal microorganism in 55 cases, from which 80% were S. pneumoniae. Fifteen percent of patients with PID died. The most prevalent pneumococcal serotypes were 19A, 35B, 19F and 6A. 10.2% of nonmeningeal strains were resistant to meropenem and 82% were resistant to TMP/SMX.
  
  
  CONCLUSIONS
  This study shows that pneumococcus was the most common bacteria isolated in the studied population, although epidemiological and laboratory-based surveillance still needs improvement.
authors.affiliation: Centro Nacional para la Salud de la Infancia y la Adolescencia, México, D.F., Mexico. aubaumar@gmail.com
authors.forename: Aurora
authors.initials: A
authors.lastname: Bautista-Márquez
authors.forename: Vesta
authors.initials: V
authors.lastname: Richardson
authors.forename: Oscar
authors.initials: O
authors.lastname: Ortiz-Orozco
authors.forename: Maria Edilia
authors.initials: ME
authors.lastname: Luna-Cruz
authors.forename: M Noemí
authors.initials: MN
authors.lastname: Carnalla-Barajas
authors.forename: Gabriela
authors.initials: G
authors.lastname: Echaniz-Avilés
authors.forename: Miriam
authors.initials: M
authors.lastname: Bobadilla-del Valle
authors.forename: Lucila
authors.initials: L
authors.lastname: Martínez-Medina
authors.forename: Ana María
authors.initials: AM
authors.lastname: Montalvo-Vázquez
authors.forename: Norma
authors.initials: N
authors.lastname: de la Re-Montaño
authors.forename: Ivette
authors.initials: I
authors.lastname: Anchondo-Martínez
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Tinoco-Favila
authors.forename: Gerardo
authors.initials: G
authors.lastname: Martínez-Aguilar
authors.forename: Israel
authors.initials: I
authors.lastname: Yberri-Zárate
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Girón-Hernández
authors.forename: José
authors.initials: J
authors.lastname: Sifuentes-Osornio
authors.forename: M Lourdes
authors.initials: ML
authors.lastname: Guerrero
authors.forename: Guillermo M
authors.initials: GM
authors.lastname: Ruiz-Palacios
mesh_terms: D000367:Age Factors; D016470:Bacteremia / Q000382:microbiology; D002675:Child, Preschool; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008800:Mexico; D011008:Pneumococcal Infections / Q000097:blood / Q000453:epidemiology* / Q000382:microbiology; D022242:Pneumococcal Vaccines; D015995:Prevalence; D011446:Prospective Studies; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000276:immunology / Q000302:isolation & purification*
chemical_list: D022242:Pneumococcal Vaccines