Persistent and Emerging Pneumococcal Carriage Serotypes in a Rural Gambian Community After 10 Years of Pneumococcal Conjugate Vaccine Pressure.
Clin Infect Dis
; 73(11): e3825-e3835, 2021 12 06.
Article
em En
| MEDLINE
| ID: mdl-32584973
ABSTRACT
BACKGROUND:
The continuing impact of pneumococcal conjugate vaccines (PCVs) in regions with high pneumococcal transmission is threatened by the persistence of vaccine serotypes (VTs) and the emergence of nonvaccine serotypes (NVTs).METHODS:
In 2016, we conducted a cross-sectional carriage survey (CSS5) in a community where PCV7 was first introduced in 2006 during a cluster-randomized trial conducted before nationwide introduction of PCV7 (2009) and PCV13 (2011). We estimated prevalence of PCV13 VT and NVT by age and compared these with earlier surveys before (CSS0), during (CSS1-3), and after the trial but before PCV13 (CSS4). Genomic analysis was conducted for the nontypeable pneumococci.RESULTS:
Prevalence of PCV13 VT carriage decreased during the 10 years between CSS0 and CSS5 across all age groups (67.6% to 13.5%, P < .001; 59.8% to 14.4%, P < .001; 43.1% to 17.9%, P < .001; and 24.0% to 5.1%, P < .001, in <2, 2-4, 5-14, and ≥15 years, respectively). However, there was no difference between CSS4 and CSS5 in children ≥2 years and adults (children <2 years, no data). The prevalence of PCV13 NVT increased between CSS0 and CSS5 for children <2 years but decreased in older children and adults. In CSS5, serotypes 3, 6A, and 19F were the most common VT and nontypeable isolates were the most common NVT. Among nontypeable isolates, 73.0% lost the ability to express a capsule. Of these, 70.8% were from a VT background.CONCLUSIONS:
The decrease in PCV13 VT that has occurred since the introduction of PCV13 appears to have plateaued. Significant carriage of these serotypes remains in all age groups.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Infecções Pneumocócicas
Tipo de estudo:
Clinical_trials
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Observational_studies
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Prevalence_studies
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Risk_factors_studies
Limite:
Adolescent
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Adult
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Child
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Humans
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Infant
País/Região como assunto:
Africa
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article