Clinical Microbiology and Antimicrobial Chemotherapy. 2019; 21(4):275-281
To estimate the prevalence of S. pneumoniae serotypes in adults aged of 18 years and older, including healthy carriers and patients with acute otitis media (AOM), community-acquired pneumonia (CAP) and invasive pneumococcal infection (IPI).
A total of 230 isolates of S. pneumoniae from 10 centers were included in the study from 01.06.2019 to 01.10.2019. Re-identification and typing using real-time PCR with 22 primer pairs were performed in the central laboratory (Institute of Antimicrobial Chemotherapy, Russia).
In healthy nasopharyngeal carriers (n = 31), the following serotypes of S. pneumoniae were detected: 19F (29.0%), 6А/В (22.6%), 3 (16.1%), 11A/D and 23F (9.7% each), 23A (6.4%), 14 and 15A/F (3.2% each); PCV-13 and PPV-23 covered 80.6% and 90.3% of those serotypes, respectively. In patients with AOM (n = 18), serotypes were: 3 (16.7%), 11A/D and 6A/B (11.1%, each), 16, 19А, 19F, 23F, 7A/F (5.55%, each); PCV-13 and PPV-23 covered 50% and 61.1% of those serotypes, respectively. Among 166 isolates from patients with CAP, the following serotypes were detected: 3 (12.0%), 19F and 6A/B (10.2%, each), 14 and 11A/D (5.4% each), 15A/F and 23A (4.8% each), 9N/L (4.2%), 18 and 22A/F (2.4% each), 19A and 23F (1.8% each), 16, 9V/A (1.2% each), 4 and 33A/33F/37 (0.6% each), non-vaccine serotypes (30.3%); PCV-13 and PPV-23 covered 45.6% and 57.0% of those serotypes, respectively. Isolates from patients with IPI (n=15) belonged to the following serotypes: 3 (26.7%), 12F, 23F and 9N/L (13.3% each), serotypes 4 and 15A/F (6.7%), non-vaccine serotype – 1 isolate (6.7%); PCV-13 and PPV-23 covered 46.7% and 73.3% of those serotypes, respectively.
The majority of S. pneumoniae serotypes in adult population in Russia are included in PPV-23, but not in PCV-13 (primarily due to serotype 11A/D). There was a high PCV-13 and PPV-23 coverage of serotypes from healthy nasopharyngeal carriers. PPV-23 covered more than 60% of clinical isolates, whereas PCV-13 covered less than 60% (AOM – 50.0%, CAP – 45.6%, IPI – 46.7%), thus indicating a potentially lower efficacy of PCV-13 in adult population.