Understand the spread of animal infections and prevent the next pandemic

BViruses can spread from animals to humans, and bats are an example of a host animal.

ImageJohnér Bildbyrå AB, Jens Rydell

Zoonotic spillover means that a disease or infectious agent is transmitted from animals to humans. Viruses, bacteria or parasites that previously only existed in animals can infect humans through changes or opportunities for contact. It occurs through direct contact with animals, through food or through vectors such as mosquitoes, ticks, or bats. The process is central to the emergence of many new infectious diseases, including pandemics such as influenza, SARS, MERS and COVID-19.

"Within PANDASIA, we investigate the socio-ecological mechanisms behind viral zoonotic spillover. The goal is to identify strategies to reduce the frequency of spillovers and the risk of pandemics through better knowledge, preparations and preventive targeted efforts," says Henrik Sjödin, researcher at the Department of Public Health and Clinical Medicine at Umeå University.

Special focus on Thailand

PANDASIA stands for "Pandemic Literacy and Viral Zoonotic Spillover Risk at the Frontline of Disease Emergence in Southeast Asia to Improve Pandemic Preparedness" and is mainly funded by the EU through Horizon Europe and by UK Research and Innovation. It is a collaboration between several research institutes in Europe and Thailand, and is led by researcher Hans Overgaard at the Norwegian University of Environmental and Biosciences.

"The project is concentrated in Southeast Asia, with a particular focus on studying preliminary stages of disease outbreaks in high-risk environments in Thailand, where data collection and field studies are combined. We want to understand the risks along gradients from natural environments to rural and urban areas, where human activity meets natural ecosystems," says Henrik Sjödin.

Mathematical models of spillover

Henrik's research group in Umeå plays a central role in modeling and analyzing the complex processes behind zoonotic spillover. To understand these mechanisms over both time and space, the group uses mathematical and quantitative models.

"We study ecological, evolutionary, sociological and epidemiological factors from a One Health perspective, which connects the health of people, animals and ecosystems."

Specifically, Henrik and his colleagues develop models based on data and empirical observations from the other research groups in the project.

"Our models function both as a tool for understanding the processes and as a platform for simulating scenarios and testing different strategies to reduce the risk of zoonotic spread."

Starting to achieve results

The Umeå group has been involved from the beginning and participated in the work of designing the application for funding from Horizon Europe. The project has been in the upstart phase, but now the researchers are starting to see concrete results. Among other things, they have identified several interesting research tracks that they are now delving into.

"For example, we investigate how socio-ecological factors affect the distribution of important host species in relation to anthropogenic activities within tropical regions, how stress levels in ecosystems and species can increase the risk of pathogens, as well as how viral properties develop evolutionarily to enable spread between species - including to humans. At the same time, we look forward to the next project phase, where we expect more and clearer results."

Collaboration requires communication

Collaboration is essential in a multidisciplinary project like this. It requires good coordination, open communication and a willingness to learn from each other.

"It is incredibly inspiring to work together with experts from different fields and combine our knowledge to reach common goals. We hope that the research within the project with joint efforts can contribute with concrete tools and guidelines to identify and prevent future potential pandemics."

Henrik Sjödin has a background in ecology and theoretical ecology. Several of the processes within infection research, the project and especially within one-health have clear ecological aspects. It is about how pathogens, such as viruses or malaria parasites, interact with their environment, to how socio-ecological systems work – including the interaction between wild hosts, disease vectors (such as mosquitoes), humans and human activities. 

ImageMattias Pettersson