Dataset Information

Vaccination of Icelandic Children with the 10-Valent Pneumococcal Vaccine Leads to a Significant Herd Effect among Adults in Iceland.

ABSTRACT: The introduction of pneumococcal conjugate vaccines (PCVs) into childhood vaccination programs has reduced carriage of vaccine serotypes and pneumococcal disease. The 10-valent PCV was introduced in Iceland in 2011. The aim of this study was to determine PCV impact on the prevalence of serotypes, genetic lineages, and antimicrobial-resistant pneumococci isolated from the lower respiratory tract (LRT) of adults. Pneumococci isolated between 2009 and 2017 at the Landspitali University Hospital were included (n?=?797). The hospital serves almost three-quarters of the Icelandic population. Isolates were serotyped and tested for antimicrobial susceptibility, and the genome of every other isolate collected between 2009 and 2014 was sequenced (n?=?275). Serotypes and multilocus sequence types (STs) were extracted from the genome data. Three study periods were defined, 2009 to 2011 (PreVac), 2012 to 2014 (PostVac-I), and 2015 to 2017 (PostVac-II). The total number of isolates and vaccine-type (VT) pneumococci decreased from PreVac to PostVac-II (n?=?314 versus n?=?230 [p?=?0.002] and n?=?170 versus n?=?33 [p?n?=?56 versus n?=?114 [p?=?0.008]). Serotype 19F decreased in the PostVac-II period; these isolates were all multidrug resistant (MDR) and were members of the Taiwan^19F-14 PMEN lineage. Serotype 6A decreased among adults ?65?years old in the PostVac-II period (p?=?0.037), while serotype 6C increased (p?=?0.021) and most serotype 6C isolates were MDR. Nonencapsulated Streptococcus pneumoniae (NESp) isolates increased among adults 18 to 64?years old in the PostVac-II period, and the majority were MDR (p?=?0.028). An overall reduction in the number of LRT samples and pneumococcus-positive cultures and significant changes in the serotype distribution became evident within 4 years, thereby demonstrating a significant herd effect.

SUBMITTER: Quirk SJ

PROVIDER: S-EPMC6440763 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Vaccination of Icelandic Children with the 10-Valent Pneumococcal Vaccine Leads to a Significant Herd Effect among Adults in Iceland.

Quirk Sigríður J SJ Haraldsson Gunnsteinn G Hjálmarsdóttir Martha Á MÁ van Tonder Andries J AJ Hrafnkelsson Birgir B Bentley Stephen D SD Haraldsson Ásgeir Á Erlendsdóttir Helga H Brueggemann Angela B AB Kristinsson Karl G KG

Journal of clinical microbiology 20190328 4

The introduction of pneumococcal conjugate vaccines (PCVs) into childhood vaccination programs has reduced carriage of vaccine serotypes and pneumococcal disease. The 10-valent PCV was introduced in Iceland in 2011. The aim of this study was to determine PCV impact on the prevalence of serotypes, genetic lineages, and antimicrobial-resistant pneumococci isolated from the lower respiratory tract (LRT) of adults. Pneumococci isolated between 2009 and 2017 at the Landspitali University Hospital wer ...[more]

PMID: 30651396

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Project description:IntroductionDiseases caused by Streptococcus pneumoniae represent a major public health problem. The purpose of this study was to compare, in the Japanese context, the projected health benefits, costs and cost-effectiveness of the latest generation of pneumococcal conjugate vaccines which may provide important insight into the potential public health impact of interventions in the context of local disease-specific epidemiology.MethodsA Markov model was used to compare two vaccination strategies which involve routine infant immunization with either the 13-valent pneumococcal conjugate vaccine (PCV-13; Prevenar 13™, Pfizer, Pearl River, NY, USA) or the 10-valent pneumococcal non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV; Synflorix™, GlaxoSmithKline Biologicals SA, Rixensart, Belgium) over a time horizon of 5 years from the healthcare provider and societal perspectives. Estimates for key model parameters were obtained from locally available databases and published literature. Incremental benefits in terms of costs and quality-adjusted life-year and cost-effectiveness were assessed.ResultsA 3 + 1 vaccination schedule for infants with PHiD-CV is expected to have a similar impact on invasive pneumococcal disease and pneumonia and a larger impact on acute otitis media-related outcomes compared with PCV-13. Assuming price parity for these vaccines, the model projected that vaccination with PHiD-CV would result in cost savings of 1.9 and 3.9 billion Japanese yen from the provider and societal perspectives, respectively. This was largely due to a reduction in highly prevalent acute otitis media. Vaccination with PHiD-CV was expected to generate a gain of 433 quality-adjusted life-years compared to PCV-13 translating into dominance over PCV-13. Sensitivity analyses showed robustness of model outcome to changes in key model parameters and substantiated that the model outcome was consistently driven by the incremental benefit of PHiD-CV in averting acute otitis media.ConclusionIn comparison to PCV-13, vaccination with PHiD-CV is projected to be cost saving for Japan from both the healthcare provider and societal perspectives.

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Dataset Information

Vaccination of Icelandic Children with the 10-Valent Pneumococcal Vaccine Leads to a Significant Herd Effect among Adults in Iceland.

Publications

Vaccination of Icelandic Children with the 10-Valent Pneumococcal Vaccine Leads to a Significant Herd Effect among Adults in Iceland.

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