Fig 1.
Sites and the nodule prevalence measured during Rapid Epidemiological Mapping of Onchocerciasis (REMO) in Ethiopia.
The internal boundaries on the map represents administrative regions. The inset figure shows the histogram of prevalence. The administrative borders are from the Global Administrative Areas (GADM) database (available at: https://gadm.org/maps.html).
Table 1.
Mean coefficient estimates and 95% Bayesian credible interval (BCI) for the environmental and socio-demographic variables in the model.
Regression coefficients for covariates are presented as a risk ratio (RR), which represents the change in prevalence for a unit change in that covariate given that all other variables are kept constant. Significant covariates are followed by an asterisk (*).
Fig 2.
Onchocerca volvulus nodule posterior prevalence map in Ethiopia generated from the geostatistical model.
(A) The mean, (B) the lower limit, and (C) the upper limit of O. volvulus nodule prevalence. The prediction interval of the prevalence map was generated from the calculated 95% BCI of fitted posterior prevalence values. The administrative borders are from the Global Administrative Areas (GADM) database (available at: https://gadm.org/maps.html).
Fig 3.
Uncertainty in the estimates of O. volvulus nodule prevalence from the model.
(A) Exceedance threshold probability map that shows the posterior predictive probability that the nodule prevalence is greater than 20%. (B) Bivariate map that shows both prevalence and the uncertainty estimates rescaled from 0 to 1. The administrative borders are from the Global Administrative Areas (GADM) database (available at: https://gadm.org/maps.html).
Fig 4.
The estimated number of pre-intervention O. volvulus nodule prevalence cases with respect to Ethiopian districts.
(A) The mean pre-intervention cases, (B) their upper and (C) lower limit were aggregated at the district level border. The regional borders are highlighted with thicker lines. The administrative borders are from the Global Administrative Areas (GADM) database (available at: https://gadm.org/maps.html).
Fig 5.
The relationship between the predicted posterior mean prevalence with the significant environmental covariates.
The curve was fitted using the gam smoothing function available in the ggplot2 package for the purpose of visualization. The shaded region around each curve represents the 95% confidence interval. Flow accumulation had a range of high magnitude compared to other covariates (values ranged from 0 to 100418). Thus, this variable was rescaled from 0 to 100 to make its range comparable with other variables.