Effect of the 13-Valent Pneumococcal Conjugate Vaccine on Nasopharyngeal Colonization by Streptococcus pneumoniae--Alaska, 2008-2012

Abstract

Background In 2010, a 13-valent pneumococcal conjugate vaccine (PCV13) replaced a 7-valent vaccine (PCV7) that contained all PCV7 serotypes plus 6 additional serotypes (PCV6+). We conducted annual surveys from 2008–2012 to determine the effect of PCV13 on colonization by pneumococcal serotypes. Methods We obtained nasopharyngeal swabs for pneumococcal identification and serotyping from residents of all ages at 8 rural villages and children age <60 months at 2 urban clinics. We conducted interviews/medical records review for all participants. Results A total of 18,207 nasopharyngeal swabs (rural=16,098; urban=2,109) were collected. From 2008–2012, 84% of rural and 90% of urban children age <5 years were age-appropriately vaccinated with a PCV. Overall pneumococcal colonization prevalence remained stable among rural (66%) and urban (35%) children age <5 years, and adults age ≥18 years (14%). Colonization by PCV6+ serotypes declined significantly among rural children age <5 years, urban children age <5, and adults age ≥18 over the course of the study (25%–5%, 22%–9%, 22%–6%, respectively). Conclusions PCV13 was rapidly introduced into the Alaska childhood immunization schedule and reduced colonization by PCV6+ serotypes among children. Unvaccinated adults also experienced comparable reductions in vaccine serotype colonization indicating substantial indirect protection from PCV13.

The impact of a pneumococcal conjugate vaccination program on the nasopharyngeal carriage, serotype distribution and antimicrobial resistance of Streptococcus pneumoniae among healthy children in Turkey

“…The second most striking observation of our study was that our county continues to harbor VT serotypes among our pediatric population, most likely as a result of serotype replacement as VT carriage was significantly decreased in the vaccinated group compared with the nonvaccinated group, a finding supported by Ozdemir et al [25]. The circulation of VTserotypes, particularly serotype 19F, corroborate the findings of previous studies [12], which determined that PCV7 was less effective in reducing serotype 19F carriage and that PCV13 does not appear to reduce serotype 19F carriage more than does PCV7 as the serotype's prevalence remained virtually unchanged in our study [13.5%] (a 3 year PCV7 period followed by a 2 year PCV13 period) and was 15.2% during the 3 year PCV7 period, as stated in the survey by Ozdemir et al [25]. However, Ozdemir et al [25] determined that serotypes 15, 22 and 35 may become the dominant NVT serotypes in the near future, as has happened in other regions of the world [15,16].…”

“…However, the number of clinical trials assessing PCV13 effectiveness against SPNP carriage was small. Most of these studies demonstrated that the carriage of PCV13 serotypes decreased; however, this resulted in shift toward non-PCV13 serotypes; overall NP carriage was not influenced by PCV13 vaccination [12][13][14]. Moreover, increased SPNP carriage of serotype 15 was noted following the introduction of PCV13, although this increase was not as significant as that observed for serotype 19A following the introduction of PCV7 [15][16][17].…”

13-Valent Pneumococcal Conjugate Vaccine: A Review of Its Use in Adults

“…Studies conducted in Alaska [43] and England [44] evaluated the impact of PCV13 on pneumococcal nasopharyngeal (PNP) carriage in adults as well as children. In Alaska, where PCV13 replaced PCV7 as part of routine childhood immunization in 2010, PNP carriage of the six additional serotypes unique to PCV13 decreased significantly over the course of the study from 2008 to 2012 among children as well as unvaccinated adults, suggesting indirect protection from PCV13 [43]. Broadly similar findings were reported in the study conducted in England [44].…”

Meningitis neumocóccica por serotipo 19 A, de curso fatal: ¿Un caso prevenible?

“…En países con vacuna conjugada 13-valente, que incluye el serotipo 3, se ha visto una protección sub-óptima para este serotipo 10 . Estudios epidemiológicos realizados en algunos estados, como Calgary y Alaska 11,12 , que han incorporado esquema de vacunación con PCV-13, han demostrado una disminución en la portación nasofaríngea reduciendo de 19,9% a 13,3%. Respecto a los serotipos específicos, datos aportados por un estudio realizado en Milán 13 , demuestran que la reducción en la portación ha sido más significativa para el serotipo 19 A.…”