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. However, 20\% or more of close contacts cannot be reached or refused vaccination, and it is predicted that the ring vaccination strategy would not be effective with such a high level of inaccessibility. In May 2019, the DRC expanded their control efforts to include a community vaccine strategy. To assess the impact of vaccination strategies for controlling Ebola epidemics in the context of variable levels of community resistance, we employed an individual-level stochastic transmission model. Our results indicate that a ring vaccination strategy  would not be effective for containing the epidemic if levels of inaccessibility are too high and estimate the 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 lower levels of inaccessibility, the probability of epidemic containment increases over time , even if probabilities are lower than they would be otherwise . For higher levels of inaccessibility,  vaccination strategies are not expected to contain the epidemic even though they help lower incidence levels, which saves lives, makes the epidemic easier to contain and reduces spread to other communities. This qualitative change occurs for both types of vaccination strategies: ring vaccination is effective for containing an outbreak until the levels of inaccessibility exceeds approximately 10\%, a combined ring and community vaccination strategy is effective until the levels of inaccessibility exceeds approximately 50\%. Our results underscore the need to enhance community engagement to public health interventions.
In the context of the ongoing Ebola epidemic in DRC , active conflict and community distrust are undermining control efforts, including vaccination strategies. In this paper, we employed an individual-level stochastic structured transmission model to assess the impact of vaccination strategies on epidemic control in the context of variable levels of household inaccessibility. We found that a ring vaccination strategy of close contacts 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 evaluate the impact of a supplemental community vaccination strategy. For lower levels of inaccessibility, the probability of epidemic containment increases over time . For higher levels of inaccessibility, even the combined ring and community vaccination strategies are not expected to contain the epidemic even though they help lower incidence levels, which saves lives, makes the epidemic easier to contain and reduces spread to other communities. We found that ring vaccination is effective for containing an outbreak until the levels of inaccessibility exceeds approximately 10\%, a combined ring and community vaccination strategy is effective until the levels of inaccessibility exceeds approximately 50\%. Our findings underscore the need to enhance community engagement to public health interventions.
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Despite a very effective vaccine
In the context of the ongoing Ebola epidemic in DRC
D
during the ongoing DRC Ebola epidemic
R
a ring vaccination strategy. However, 20\% or more of close contacts cannot be reached or refused vaccination, and it is predicted that the ring vaccination strategy would not be effective with such a high level of inaccessibility. In May 2019, the DRC expanded their control efforts to include a community vaccine strategy. To
vaccination strategies. In this paper, we employed an individual-level stochastic structured transmission model to
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for controlling Ebola epidemics
on epidemic control
R
community resistance, we employed an individual-level stochastic transmission model. Our results indicate
household inaccessibility. We found
A
of close contacts
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if levels of inaccessibility are too high and estimate
in the context of significant delays to vaccinating contacts even for low levels of household inaccessibility and evaluate
D
Our key results are that as levels of inaccessibility increase, there is a qualitative change in the effectiveness of the vaccination strategy.
D
, even if probabilities are lower than they would be otherwise
A
even the combined ring and community
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This qualitative change occurs for both types of vaccination strategies:
We found that
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results
findings