Researchers believe that they have developed a way to predict how animal diseases spread in humans. It is important to develop such methods since more than 60% of emerging infectious diseases originate in animals. Their model of study was Lassa fever that is spread by rats, and they predict that human cases of disease will increase up to twice as many as now in Africa by 2070.
Similar methods can also be employed to predict the outbreak of other viral epidemics like Zika and Ebola.
Lassa fever affects individuals ranging from 0.1 to 1 million people a year in western sub-Saharan Africa. Rats found in those locality can spread virus to humans.
Professor Kate Jones from Centre for Biodiversity and Environment Research at UCL looked at 400 known outbreaks of Lassa fever between years 1967 -2012. He, along with his team, developed a model that can calculate how often people can come into contact with this zoonotic disease (disease that spreads from animal to human). The result was astonishing as it showed that West African countries are more at risk of Lassa spreading events than previously estimated.
Dr. Jones and his colleagues from University of Cambridge and Zoological Society London reported in the journal Methods of Ecology and Evolution that, “Our model suggests that in future, it is likely to become a greater burden on local communities spreading to more areas with approximately twice as many spillover events predicted by 2070”.
The method takes into account the change in population growth and the way humans dwell in that region. They believe that the projected increase is mainly due to climate change that enables rats (M. natalensis) to pass the virus to humans living in hot and humid conditions. Also, a rise in population means more people coming into contact with the rodent.
“Our 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, ” said co-researcher Dr David Redding of UCL to BBC.
They conclude that the model could help communities prepare and respond to disease outbreaks. The model could also be refined to include diseases such as Ebola and Zika that may give better insights.
Study source: BBC News