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bioRxiv · 10.1101/494492

Optimizing the use of the Men-ACWY conjugated vaccine to control the developing meningococcal W disease outbreak in the Netherlands, a rapid analysis.

van Hoek, A. J.·Knol, M.·de Melker, H.·Wallinga, J.
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Abstract

BackgroundThere is a developing outbreak of Neisseria meningitidis serotype W (MenW) in the Netherlands. In response, those aged 14 months and 14 years are vaccinated with the conjugated MenACWY vaccine. In the spring of 2018 we aimed to explore the impact of adding a one-off catch-up campaign targeting those aged 15-18 years on the transmission of MenW and the cost-effectiveness of such a campaign.\n\nMethodsWe estimated the growth rate of the MenW outbreak and quantified the impact of various targeted vaccination strategies on the reproductive number, and subsequently projected the future incidence with and without vaccination. Future cases were expressed in costs and QALYS and the incremental cost-effectiveness ratio was obtained.\n\nResultsWe estimate a reproductive number of around 1.4 (95%CI 1.2-1.7) over the period February 2016-February 2018. Adding the catch-up campaign reduces the reproductive number five years earlier than without a catch-up campaign, to a level around 1.2. The vaccination campaign, including the catch-up, will prevent around 100 cases per year in our base case scenario. Given the projected impact and realistic assumptions on costs and QALYs, adding the catch-up can be considered cost-effective using a threshold of {euro}20,000 per QALY.\n\nConclusionAdding the catch-up campaign targeting those aged 15-18 brings the impact of vaccination on reducing transmission five years forward and directly prevents a high-incidence age group from carriage and disease. Such a campaign can be considered cost-effective. Our study did underpin the decision to introduce a catch-up campaign in spring 2019. Furthermore, our applied method can be of interest for anyone solving vaccine allocation questions in a developing outbreak.

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van Hoek, A. J., Knol, M., de Melker, H., Wallinga, J.. 2018-12-14. Optimizing the use of the Men-ACWY conjugated vaccine to control the developing meningococcal W disease outbreak in the Netherlands, a rapid analysis.. https://doi.org/10.1101/494492

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