Serotype distribution of pneumococci isolated from pediatric patients with acute otitis media and invasive infection, and potential coverage of pneumococcal conjugated vaccines

Servicio de Microbiología, Hospital de Pediatría "Prof. Dr. Juan P. Garrahan", Combate de los Pozos 1881 (1245) Ciudad Autónoma de Buenos Aires, Argentina.
Revista Argentina de microbiología (Impact Factor: 0.8). 04/2013; 45(1):27-33.
Source: PubMed


A 16-month prospective, descriptive study was conducted on pneumococcal serotype distribution isolated from children with acute otitis media (AOM) and invasive infections (INV). Eighty-nine children with pneumococcal INV and 324 with a first episode of AOM were included. Bacterial pathogens (N = 326) were isolated from the middle-ear fluid of 250 patients. A total of 30 pneumococcal serotypes were identified. Prevalent serotypes were 14, 19A, 9V, 3, 19F, 6A, 23F, and 18C in AOM and 14, 1, 19A, 5, 12F, 6B, and 18C in INV. Potential coverage with PCV10 vaccine would be 46.5 % and 60.7 % for pneumococci involved in AOM and INV, respectively; it would be 71.7 % and 73 % with PCV13. PCV10, conjugated with a Haemophilus protein, would have an immunologic coverage of 39.9 % for AOM vs. 18.5 % with PCV13. However, differences in the prevention of INV were crucial for the decision to include the 13-valent vaccine in the national calendar for children less than two years old in Argentina.

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Available from: Horacio A Lopardo, Apr 20, 2015
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    • "This finding is similar to that recently reported in a study from China, which demonstrated that serotype 19A strains were more frequently isolated from children with IPD [22]. However, our findings differed from those recently reported in a study from Argentina, which showed that serotypes 14, 1, 19A, 5, 12F, 6B, and 18C were the most prevalent serotypes in patients with IPD [23]. In our study, serotype 23A was the second most common serotype in adult patients (15.9%), but only accounted for 9.7% of cases of IPD in children. "
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