Number of expected infections generated in a facility from model simulations comparing random and systematic testing strategies across transmission scenarios, test frequencies, and delays isolating infectious individuals who have tested positive.

Systematic testing strategies (■, ➕) prevent more infections than random strategies (●, ▲) across all transmission scenarios (indicated by community prevalence across the x axis and by reproduction number across the panels) and test frequencies (indicated by different colored symbols with blue corresponding to the highest test frequency of 4 tests per week and red the lowest test frequency of biweekly testing). More infections are expected in transmission scenarios with higher within-facility and higher community prevalence. Preventing delays between testing and isolation of positives (squares compared to crosses and triangles compared to circles) and increasing test frequency (red = lowest frequency, blue = highest frequency) also reduces the number of infections. The horizontal gray line serves as a reference to assess the testing frequency needed to maintain (corresponding to one infection every ten days) across different transmission scenarios. Error bars represent the interquartile range of derived from 100 simulations per scenario run for 180 days among 700 staff.</p

Analytic framework exploring effects of variable infectiousness through time, testing frequencies, and delays on SARS-CoV-2 transmission.

A) Example infectiousness profile for , tlatent = 4, tincubation = 5, tinfectious = 9, with line indicating infectiousness (rt) through time and shaded area demonstrating infectiousness slice removed if tiso = 7, leading to . B) as a function of tiso with same parameters as in A and point indicating scenario depicted in A. C) Boxplots showing distributions of as a function of testing frequency, f, and delay in obtaining test results, d, incorporating uncertainty in tlatent, tincubation, and tinfectious by drawing n = 100 parameter sets for each, with baseline . Boxplots indicate median, interquartile range, and full range of values of . D) Probability isolation occurs as a function of testing frequency, f, delay in obtaining test results, d, and days from exposure to isolation τ, i.e. tiso≤τ, demonstrating that delays in obtaining test results substantially reduce the probability of prompt isolation, particularly among most frequent testing scenarios.</p

Distributions and parameter values used in analytic framework and model simulations.

The latent period is defined as the time between exposure and onset of infectiousness, the incubation period as the time between exposure and both symptoms and peak infectiousness (even in the absence of symptoms), and the infectious period as the total time a case is infectious.</p

Inclusivity in global research questionnaire.

The tenth Ebola Virus Disease (EVD) outbreak (2018–2020, North Kivu, Ituri, South Kivu) in the Democratic Republic of the Congo (DRC) was the second-largest EVD outbreak in history. During this outbreak, Ebola vaccination was an integral part of the EVD response. We evaluated community perceptions toward Ebola vaccination and identified correlates of Ebola vaccine uptake among high-risk community members in North Kivu, DRC. In March 2021, a cross-sectional survey among adults was implemented in three health zones. We employed a sampling approach mimicking ring vaccination, targeting EVD survivors, their household members, and their neighbors. Outbreak experiences and perceptions toward the Ebola vaccine were assessed, and modified Poisson regression was used to identify correlates of Ebola vaccine uptake among those offered vaccination. Among the 631 individuals surveyed, most (90.2%) reported a high perceived risk of EVD and 71.6% believed that the vaccine could reduce EVD severity; however, 63.7% believed the vaccine had serious side effects. Among the 474 individuals who had been offered vaccination, 397 (83.8%) received the vaccine, 180 (45.3%) of those vaccinated received the vaccine after two or more offers. Correlates positively associated with vaccine uptake included having heard positive information about the vaccine (RR 1.30, 95% CI 1.06–1.60), the belief that the vaccine could prevent EVD (RR 1.23, 95% CI 1.09–1.39), and reporting that religion influenced all decisions (RR 1.13, 95% CI 1.02–1.25). Ebola vaccine uptake was high in this population, although mixed attitudes and vaccine delays were common. Communicating positive vaccine information, emphasizing the efficacy of the Ebola vaccine, and engaging religious leaders to promote vaccination may aid in increasing Ebola vaccine uptake during future outbreaks.</div

Ebola vaccine eligibility, uptake, and the number of offers prior to vaccine receipt, North Kivu, Democratic Republic of the Congo, 2021.

Ebola vaccine eligibility, uptake, and the number of offers prior to vaccine receipt, North Kivu, Democratic Republic of the Congo, 2021.</p

Reasons for declining vaccination among eligible but unvaccinated community members, North Kivu, Democratic Republic of the Congo, 2021.

Reasons for declining vaccination among eligible but unvaccinated community members, North Kivu, Democratic Republic of the Congo, 2021.</p

Map of health zones (Beni, Butembo, Mabalako) surveyed in North Kivu, Democratic Republic of the Congo, March 2021.

Source:https://data.humdata.org/dataset/rdc-statistiques-des-populations. (TIFF)</p

Positive and negative information heard about the Ebola vaccine, North Kivu, Democratic Republic of the Congo, 2021.

Positive and negative information heard about the Ebola vaccine, North Kivu, Democratic Republic of the Congo, 2021.</p

Sociodemographic characteristics of the surveyed community members, North Kivu, Democratic Republic of the Congo, 2021.

Sociodemographic characteristics of the surveyed community members, North Kivu, Democratic Republic of the Congo, 2021.</p

Correlates of Ebola vaccine uptake, using modified Poisson regression among community members eligible and offered vaccination during the tenth EVD outbreak, North Kivu, Democratic Republic of the Congo, 2021.

Correlates of Ebola vaccine uptake, using modified Poisson regression among community members eligible and offered vaccination during the tenth EVD outbreak, North Kivu, Democratic Republic of the Congo, 2021.</p