Predictable growth, expanded risk: West Nile virus in Italy, 2025

In 2025, the West Nile virus shifted from the northern areas to a nationwide threat in Italy. Severe cases and deaths were higher than every previous wave; however, the outbreak’s increase still followed a predictable growth pattern that we can model with a Richards growth model. The problem is not analytics—it is using them fast enough. We propose three low-regret moves: set automatic early-action triggers everywhere, publish weekly, plain-language forecasts, and make prevention routine.