Vaccination strategies to control Ebola epidemics in the context of variable household inaccessibility levels.
Despite a very effective vaccine, active conflict and community distrust during the ongoing DRC Ebola epidemic are undermining control efforts, including a ring vaccination strategy that requires the prompt immunization of close contacts of infected individuals. However, in April 2019, it was report...
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ftdoajarticles:oai:doaj.org/article:5813de4085b747099d99a1b454162995 2023-05-15T15:15:31+02:00 Vaccination strategies to control Ebola epidemics in the context of variable household inaccessibility levels. Gerardo Chowell Amna Tariq Maria Kiskowski 2019-11-01T00:00:00Z https://doi.org/10.1371/journal.pntd.0007814 https://doaj.org/article/5813de4085b747099d99a1b454162995 EN eng Public Library of Science (PLoS) https://doi.org/10.1371/journal.pntd.0007814 https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 1935-2727 1935-2735 doi:10.1371/journal.pntd.0007814 https://doaj.org/article/5813de4085b747099d99a1b454162995 PLoS Neglected Tropical Diseases, Vol 13, Iss 11, p e0007814 (2019) Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 article 2019 ftdoajarticles https://doi.org/10.1371/journal.pntd.0007814 2022-12-31T07:36:44Z Despite a very effective vaccine, active conflict and community distrust during the ongoing DRC Ebola epidemic are undermining control efforts, including a ring vaccination strategy that requires the prompt immunization of close contacts of infected individuals. However, in April 2019, it was reported 20% or more of close contacts cannot be reached or refuse vaccination, and it is predicted that the ring vaccination strategy would not be effective with such a high level of inaccessibility. The vaccination strategy is now incorporating a "third ring" community-level vaccination that targets members of communities even if they are not known contacts of Ebola cases. To assess the impact of vaccination strategies for controlling Ebola epidemics in the context of variable levels of community accessibility, we employed an individual-level stochastic transmission model that incorporates four sources of heterogeneity: a proportion of the population is inaccessible for contact tracing and vaccination due to lack of confidence in interventions or geographic inaccessibility, two levels of population mixing resembling household and community transmission, two types of vaccine doses with different time periods until immunity, and transmission rates that depend on spatial distance. Our results indicate that a ring vaccination strategy alone would not be effective for containing the epidemic in the context of significant delays to vaccinating contacts even for low levels of household inaccessibility and affirm the positive impact of a supplemental community vaccination strategy. Our key results are that as levels of inaccessibility increase, there is a qualitative change in the effectiveness of the vaccination strategy. For higher levels of vaccine access, the probability that the epidemic will end steadily increases over time, even if probabilities are lower than they would be otherwise with full community participation. For levels of vaccine access that are too low, however, the vaccination strategies are not expected to be ... Article in Journal/Newspaper Arctic Directory of Open Access Journals: DOAJ Articles Arctic PLOS Neglected Tropical Diseases 13 11 e0007814 |
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Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
language |
English |
topic |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
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Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 Gerardo Chowell Amna Tariq Maria Kiskowski Vaccination strategies to control Ebola epidemics in the context of variable household inaccessibility levels. |
topic_facet |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
description |
Despite a very effective vaccine, active conflict and community distrust during the ongoing DRC Ebola epidemic are undermining control efforts, including a ring vaccination strategy that requires the prompt immunization of close contacts of infected individuals. However, in April 2019, it was reported 20% or more of close contacts cannot be reached or refuse vaccination, and it is predicted that the ring vaccination strategy would not be effective with such a high level of inaccessibility. The vaccination strategy is now incorporating a "third ring" community-level vaccination that targets members of communities even if they are not known contacts of Ebola cases. To assess the impact of vaccination strategies for controlling Ebola epidemics in the context of variable levels of community accessibility, we employed an individual-level stochastic transmission model that incorporates four sources of heterogeneity: a proportion of the population is inaccessible for contact tracing and vaccination due to lack of confidence in interventions or geographic inaccessibility, two levels of population mixing resembling household and community transmission, two types of vaccine doses with different time periods until immunity, and transmission rates that depend on spatial distance. Our results indicate that a ring vaccination strategy alone would not be effective for containing the epidemic in the context of significant delays to vaccinating contacts even for low levels of household inaccessibility and affirm the positive impact of a supplemental community vaccination strategy. Our key results are that as levels of inaccessibility increase, there is a qualitative change in the effectiveness of the vaccination strategy. For higher levels of vaccine access, the probability that the epidemic will end steadily increases over time, even if probabilities are lower than they would be otherwise with full community participation. For levels of vaccine access that are too low, however, the vaccination strategies are not expected to be ... |
format |
Article in Journal/Newspaper |
author |
Gerardo Chowell Amna Tariq Maria Kiskowski |
author_facet |
Gerardo Chowell Amna Tariq Maria Kiskowski |
author_sort |
Gerardo Chowell |
title |
Vaccination strategies to control Ebola epidemics in the context of variable household inaccessibility levels. |
title_short |
Vaccination strategies to control Ebola epidemics in the context of variable household inaccessibility levels. |
title_full |
Vaccination strategies to control Ebola epidemics in the context of variable household inaccessibility levels. |
title_fullStr |
Vaccination strategies to control Ebola epidemics in the context of variable household inaccessibility levels. |
title_full_unstemmed |
Vaccination strategies to control Ebola epidemics in the context of variable household inaccessibility levels. |
title_sort |
vaccination strategies to control ebola epidemics in the context of variable household inaccessibility levels. |
publisher |
Public Library of Science (PLoS) |
publishDate |
2019 |
url |
https://doi.org/10.1371/journal.pntd.0007814 https://doaj.org/article/5813de4085b747099d99a1b454162995 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
PLoS Neglected Tropical Diseases, Vol 13, Iss 11, p e0007814 (2019) |
op_relation |
https://doi.org/10.1371/journal.pntd.0007814 https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 1935-2727 1935-2735 doi:10.1371/journal.pntd.0007814 https://doaj.org/article/5813de4085b747099d99a1b454162995 |
op_doi |
https://doi.org/10.1371/journal.pntd.0007814 |
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PLOS Neglected Tropical Diseases |
container_volume |
13 |
container_issue |
11 |
container_start_page |
e0007814 |
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