Nasopharyngeal s. pneumoniae carriage and density in Belgian infants after 9â¯years of pneumococcal conjugate vaccine programme.
Vaccine
; 36(1): 15-22, 2018 01 02.
Article
em En
| MEDLINE
| ID: mdl-29180027
ABSTRACT
BACKGROUND:
In Belgium, the infant pneumococcal conjugate vaccine (PCV) programme changed from PCV7 (2007-2011) to PCV13 (2011-2015) and to PCV10 (2015-2016). A 3-year nasopharyngeal carriage study was initiated during the programme switch in 2016. Main objective of the year 1 assessment was to obtain a baseline measurement of pneumococcal carriage prevalence, carriage density, serotype distribution and antibiotic resistance. MATERIALS/METHODS:
Two infant populations aged 6-30â¯months and without use of antibiotics in the seven days prior to sampling were approached (1) attending one of 85 randomly selected day-care centres (DCC); (2) presenting with AOM at study-trained general practitioners and paediatricians. Demographic and clinical characteristics were documented and a single nasopharyngeal swab was taken. S. pneumoniae were cultured, screened for antibiotic resistance and serotyped, and quantitative Taqman real-time PCR (qRT-PCR) targeting LytA was performed.RESULTS:
Culture-based (DCC 462/760; 60.8% - AOM 27/39; 69.2%) and LytA-based (DCC 603/753; 80.1% - AOM 32/39; 82.1%) carriage prevalence was high. Average pneumococcal DNA load in LytA-positive day-care samples was 6.5â¯×â¯106 copies/µl (95%CIâ¯=â¯3.9-9.2â¯×â¯106, medianâ¯=â¯3.5â¯×â¯105); DNA load was positively associated with signs of common cold and negatively with previous antibiotic use. Culture-based frequency of 13 pneumococcal vaccine (PCV) serotypes was 5.4% in DCC and 7.7% in AOM, with 19F and 14 being most frequent, and frequencies below 0.5% for serotypes 3, 6A, 19A in both populations. Predominant non-PCV serotypes were 23B and 23A in day-care and 11A in infants with AOM. In day-care, resistance to penicillin was rare (<0.5%) and absent against levofloxacin; 32.7% and 16.9% isolates were cotrimoxazole- and erythromycin-resistant respectively.CONCLUSION:
Four years after PCV13 introduction in the vaccination programme, PCV13 serotype carriage was rare in infants throughout Belgium and penicillin resistance was rare. Continued surveillance in the context of a PCV programme switch is necessary.Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Infecções Pneumocócicas
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Streptococcus pneumoniae
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Portador Sadio
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Nasofaringe
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Programas de Imunização
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Vacinas Pneumocócicas
Tipo de estudo:
Prevalence_studies
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Risk_factors_studies
Limite:
Child, preschool
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Female
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Humans
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Infant
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Male
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article