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Photo of a woman in a USAID jumpsuit putting up a Covid-19 poster in Madagascar
Source: USAID ACCESS Program/MSH

More than 70 percent of new, emerging, and re-emerging infectious diseases originate from animals. The COVID-19 pandemic demonstrates the massive global risks that can occur when zoonotic diseases spill over to humans.

For over a decade, USAID has invested in understanding the risks presented by the spillover of zoonotic diseases to humans. USAID's extensive work has shown that outbreaks can start—and stop—at the country level and that early country-level, country-led interventions are key to preventing and reducing the impact of outbreaks.

Strategies to Prevent (STOP) Spillover, a USAID-funded project led by Tufts University, is a global consortium of experts in human, animal, and environmental health who will take the next step in understanding and addressing the risks posed by known zoonotic viruses that have the potential to spill over and cause pandemic crises.

The STOP Spillover project provides a critical opportunity to enhance global understanding of the complex drivers of viral spillover and augment sustainable national capacities in risk analysis and mitigation, spillover intervention, and behavior change.

STOP Spillover will strengthen capacity in priority countries to:

1 Monitor, analyze, and characterize the risk of priority zoonotic viruses spilling over from animals to people.
2Develop, test, and implement interventions and policies to reduce the risk of priority viral zoonotic spillover.
3If spillover occurs, mitigate the amplification and spread of priority zoonotic viral diseases.

How We Work

Human behavior drives the evolution and epidemiology of infectious diseases, and we share pathogens with species we contact most closely and consistently. Some of our shared pathogens—typically viruses—can cause outbreaks, epidemics, and pandemics that leave indelible marks on our societies. Human behaviors are fundamentally linked to planetary changes and our globalized economy and are deeply embedded in cultural beliefs, practices, and preferences.

In our approach, it is not enough to know what to do to reduce spillover and amplification risks. We must also help partners gain and institutionalize knowledge in existing local systems, adapt learning to their context, and continuously expand on newfound expertise. Our consortium’s vision is for priority countries across Africa and Asia to gain critical knowledge about their spillover ecosystems and refine and use that knowledge effectively, efficiently, and sustainably to reduce the risk of zoonotic viral spillover and spread.

We will achieve our goal through equitable partnerships with local communities, colleagues, and institutions.

Led by Regional and Local Partners

Photo of a group doing virus sampling with USAID PREDICT project
Source: Richard Nyberg, USAID

We will work through the Africa One Health University Network (AFROHUN), the Southeast Asia One Health University Network (SEAOHUN), and other excellent partners to promote national commitment, empower local expertise, and facilitate South-South collaboration.

Implemented by Local Teams

Our model depends upon grassroots Country Teams and One Health-Design Research and Mentorship (OH-DReaM) working groups that partner with high-risk communities and local stakeholders. These implementing partners are supported by Resource Hubs that offer expertise, tools, and mentorship to enable the identification of priority pathogens and the mitigation of viral spillover, amplification, and spread.

Partnered with Governments

Government engagement and partnerships are key to achieving STOP Spillover’s objectives and the sustainable reduction of country and community risk. We will work with governments to enhance evidence-based, diverse surveillance approaches for targeted priority viral pathogens. STOP Spillover will build on existing systems, including routine country-level surveillance and, importantly, collect information required to strengthen country capacity to develop, test, and implement spillover interventions.

The STOP Spillover project also welcomes collaborative relationships at all levels with existing projects, groups, governments, and other stakeholders.

Committed to Sustainability

STOP Spillover will prioritize sustainable approaches that help to ensure partner countries are well-prepared to respond to and prevent outbreaks, both now and in the future. We will integrate and institutionalize capabilities through in-country training, the creation of risk analysis and mapping tools, and by working with public health officials to strengthen surveillance and research. And while STOP Spillover will focus on priority viral threats that continue to pose the greatest public health risk—including Ebola, Lassa, Marburg, Nipah, animal-origin coronaviruses, and animal-origin zoonotic influenza viruses—the capacities developed over the life of the project will help to ensure that partner countries are better prepared to prevent the spread of these and future zoonotic viruses.