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bioRxiv · 10.1101/532085

Dose-specific effectiveness of 7- and 13-valent pneumococcal conjugate vaccines against vaccine-serotype Streptococcus pneumoniae colonization: a matched, case-control study

Lewnard, J. A.·Givon-Lavi, N.·Dagan, R.
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Abstract

BackgroundReduced-dose pneumococcal conjugate vaccine (PCV) schedules are under consideration in countries where children are currently recommended to receive three PCV doses. However, dose-specific PCV effectiveness against vaccine-serotype colonization is uncertain. MethodsFrom 2009-2016, we conducted surveillance of pneumococcal carriage in southern Israel, where PCV is administered at ages 2, 4, and 12 months (2+1 schedule). We obtained nasopharyngeal swabs and vaccination histories from 4245 children ages 0-59 months without symptoms of diseases that could be caused by pneumococci. In a case-control analysis, we measured protection against vaccine-serotype colonization as one minus the matched odds ratio for PCV doses received. ResultsAt ages 5-12 months, a second PCV7/13 dose increased protection against PCV7-serotype carriage from -23.6% (95%CI: -209.7-39.1%) to 27.1% (-69.2-64.5%), and a second PCV13 dose increased protection against carriage of all PCV13 serotypes from -54.8% (-404.3-39.1%) to 23.4% (- 128.5-67.1%). At ages 13-24 months, a third PCV7/13 dose increased protection against PCV7-serotype carriage from 32.4% (-8.4-58.0%) to 74.1% (58.4-84.6%), and a third PCV13 dose increased protection against carriage of all PCV13 serotypes from -50.0% (-194.0-42.7%) to 49.7% (15.8-83.3%). On average, each PCV13 dose conferred 37.7% (7.0-61.8%) greater protection against carriage of serotypes 1, 5, 6A, 7F, and 19A than carriage of serotype 3. PCV13-derived protection against carriage of serotypes 1, 5, 6A, 7F, and 19A was equivalent to PCV7/13-derived protection against carriage of PCV7 serotypes. ConclusionsIn a setting implementing a 2+1 PCV schedule, protection against vaccine-serotype colonization is sustained primarily by the third dose.

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Lewnard, J. A., Givon-Lavi, N., Dagan, R.. 2019-02-01. Dose-specific effectiveness of 7- and 13-valent pneumococcal conjugate vaccines against vaccine-serotype Streptococcus pneumoniae colonization: a matched, case-control study. https://doi.org/10.1101/532085

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