Environmental changes help predict disease outbreaks

A team of researchers has come up with a model to predict the outbreaks of zoonotic diseases using environmental changes, allowing communities to be prepared for the epidemics.

The model, developed by UCL researchers, is based on changes in climate, population growth and land use.

More than 60 perecent of emerging infectious diseases are zoonotic, those originating in livestock or wildlife, and although, Ebola and Zika are well-known, there are many other diseases including Rift Valley fever and Lassa fever which affect thousands already and are predicted to spread with changing environmental factors.

Lead author Kate Jones said that the model can help decision-makers assess the likely impact of any interventions or change in national or international government policies, such as the conversion of grasslands to agricultural lands, on zoonotic transmission. Importantly, the model also has the potential to look at the impact of global change on many diseases at once, to understand any trade-offs that decision-makers may have to be make.

Co-author Dr David Redding added that the new approach successfully predicts outbreaks of individual diseases by pairing the changes in the host's distribution as the environment changes with the mechanics of how that disease spreads from animals to people, which hasn't been done before. It allows researchers to calculate how often people are likely to come into contact with disease-carrying animals and their risk of the virus spilling over.

The researchers said that the model could be refined to consider zoonotic disease transmission within human populations by including the impact of travel infrastructure, human-to-human contact rates and poverty.

The research is published in Methods in Ecology and Evolution.