Results of logistic regression of Rift Valley fever presence/absence on cumulative rainfall anomalies.

Logistic regression of Rift Valley fever presence/absence on cumulative rainfall anomalies over a 4 month period. For each region, the top row presents results for the intercept term (β0) and the bottom row (β1) for the rainfall anomaly term. Regional Rift Valley fever outbreaks were significantly positively correlated with persistently above-normal cumulative rainfall over a 4 month period (99.9% confidence, β1>0), except in Madagascar (β1