Evaluating vaccination strategies for reducing infant respiratory syncytial virus infection in low-income settings

BACKGROUND: Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract disease and related hospitalization of young children in least developed countries. Individuals are repeatedly infected, but it is the first exposure, often in early infancy, that results in the vast majority...

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Autores principales: Poletti, Piero, Merler, Stefano, Ajelli, Marco, Manfredi, Piero, Munywoki, Patrick K, Nokes, D James, Melegaro, Alessia
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4372170/
https://www.ncbi.nlm.nih.gov/pubmed/25857701
http://dx.doi.org/10.1186/s12916-015-0283-x
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author Poletti, Piero
Merler, Stefano
Ajelli, Marco
Manfredi, Piero
Munywoki, Patrick K
Nokes, D James
Melegaro, Alessia
author_facet Poletti, Piero
Merler, Stefano
Ajelli, Marco
Manfredi, Piero
Munywoki, Patrick K
Nokes, D James
Melegaro, Alessia
author_sort Poletti, Piero
collection PubMed
description BACKGROUND: Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract disease and related hospitalization of young children in least developed countries. Individuals are repeatedly infected, but it is the first exposure, often in early infancy, that results in the vast majority of severe RSV disease. Unfortunately, due to immunological immaturity, infants are a problematic RSV vaccine target. Several trials are ongoing to identify a suitable candidate vaccine and target group, but no immunization program is yet in place. METHODS: In this work, an individual-based model that explicitly accounts for the socio-demographic population structure is developed to investigate RSV transmission patterns in a rural setting of Kenya and to evaluate the potential effectiveness of alternative population targets in reducing RSV infant infection. RESULTS: We find that household transmission is responsible for 39% of infant infections and that school-age children are the main source of infection within the household, causing around 55% of cases. Moreover, assuming a vaccine-induced protection equivalent to that of natural infection, our results show that annual vaccination of students is the only alternative strategy to routine immunization of infants able to trigger a relevant and persistent reduction of infant infection (on average, of 35.6% versus 41.5% in 10 years of vaccination). Interestingly, if vaccination of pregnant women boosts maternal antibody protection in infants by an additional 4 months, RSV infant infection will be reduced by 31.5%. CONCLUSIONS: These preliminary evaluations support the efforts to develop vaccines and related strategies that go beyond targeting vaccines to those at highest risk of severe disease. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12916-015-0283-x) contains supplementary material, which is available to authorized users.
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spelling pubmed-43721702015-03-25 Evaluating vaccination strategies for reducing infant respiratory syncytial virus infection in low-income settings Poletti, Piero Merler, Stefano Ajelli, Marco Manfredi, Piero Munywoki, Patrick K Nokes, D James Melegaro, Alessia BMC Med Research Article BACKGROUND: Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract disease and related hospitalization of young children in least developed countries. Individuals are repeatedly infected, but it is the first exposure, often in early infancy, that results in the vast majority of severe RSV disease. Unfortunately, due to immunological immaturity, infants are a problematic RSV vaccine target. Several trials are ongoing to identify a suitable candidate vaccine and target group, but no immunization program is yet in place. METHODS: In this work, an individual-based model that explicitly accounts for the socio-demographic population structure is developed to investigate RSV transmission patterns in a rural setting of Kenya and to evaluate the potential effectiveness of alternative population targets in reducing RSV infant infection. RESULTS: We find that household transmission is responsible for 39% of infant infections and that school-age children are the main source of infection within the household, causing around 55% of cases. Moreover, assuming a vaccine-induced protection equivalent to that of natural infection, our results show that annual vaccination of students is the only alternative strategy to routine immunization of infants able to trigger a relevant and persistent reduction of infant infection (on average, of 35.6% versus 41.5% in 10 years of vaccination). Interestingly, if vaccination of pregnant women boosts maternal antibody protection in infants by an additional 4 months, RSV infant infection will be reduced by 31.5%. CONCLUSIONS: These preliminary evaluations support the efforts to develop vaccines and related strategies that go beyond targeting vaccines to those at highest risk of severe disease. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12916-015-0283-x) contains supplementary material, which is available to authorized users. BioMed Central 2015-03-10 /pmc/articles/PMC4372170/ /pubmed/25857701 http://dx.doi.org/10.1186/s12916-015-0283-x Text en © Poletti et al.; licensee BioMed Central. 2015 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
spellingShingle Research Article
Poletti, Piero
Merler, Stefano
Ajelli, Marco
Manfredi, Piero
Munywoki, Patrick K
Nokes, D James
Melegaro, Alessia
Evaluating vaccination strategies for reducing infant respiratory syncytial virus infection in low-income settings
title Evaluating vaccination strategies for reducing infant respiratory syncytial virus infection in low-income settings
title_full Evaluating vaccination strategies for reducing infant respiratory syncytial virus infection in low-income settings
title_fullStr Evaluating vaccination strategies for reducing infant respiratory syncytial virus infection in low-income settings
title_full_unstemmed Evaluating vaccination strategies for reducing infant respiratory syncytial virus infection in low-income settings
title_short Evaluating vaccination strategies for reducing infant respiratory syncytial virus infection in low-income settings
title_sort evaluating vaccination strategies for reducing infant respiratory syncytial virus infection in low-income settings
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4372170/
https://www.ncbi.nlm.nih.gov/pubmed/25857701
http://dx.doi.org/10.1186/s12916-015-0283-x
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