Fig. 4: Spatial overlap between wild shorebird contact and H5 binding exists that is not seen when comparing domesticated poultry contact and H5 binding.
a Estimated mean probability of wild shorebird contact and estimated mean probability of high H5 binding (to A/Duck/Laos/3295/2006) from Bayesian geostatistical models predicted across the study site in Northern Sabah (Fig. 1). Posterior probabilities were estimated using 1000 posterior samples. These posterior probabilities were then used to predict the probability of the outcome variable (H5 binding or species distribution) across the whole study region at 30 m spatial resolution. A total of n = 2000 samples were tested in duplicate by ELISA at a 1:50 dilution, and IgG binding to H5 HA was measured in absorbance units (AU). High H5 binding is considered greater than 2.0 AU based on comparison to the control cohorts. b Adjusted odds ratios for environmental predictors in mixed effects modelling of contact and H5 binding are shown along with 95% confidence intervals for each odds ratio and statistical significance, where p ≤ 0.10 (.), p ≤ 0.05 (*), p ≤ 0.01 (**), p ≤ 0.001 (***). Odds ratios greater than 1 (shown in blue) indicate a factor that increases the odds of high H5 binding or of migratory shorebird sightings. Odds ratios <1 (shown in red) decrease the odds of those outcomes. p-values for the risk factors for the odds of wild bird sightings are 3.07 × 10−6 (model intercept), 6.88 × 10−10 (Euclidean distance from roads), 0.001 (elevation in meters above sea level), 0.001 (distance from the sea in meters), 6.90 × 10−5 (maximum temperature of warmest month in °C), 4.68 × 10−9 (precipitation of the wettest month in mm), 0.094 (distance from bush forest in meters) and 0.01 (distance from old forest in meters). p-values for the risk factors for the odds of H5N1 binding are as follows: 0.018 (normalised differential vegetation index), 3.93 × 10−6 (elevation in meters above sea level), 1.67 × 10−6 (distance from the sea in meters), 4.79 × 10−5 (mean diurnal range in °C), 4.85 × 10−7 (minimum temperature of coldest month in °C), 0.04 (precipitation of the wettest month in mm), 0.084 (precipitation seasonality), and 0.027 (distance from irrigated farmland in metres). Source data are provided as a Source Data file including mean posterior estimates, odds ratios, and confidence intervals.
