Stop Spillover

Originally published as a digital essay for a university course April 22, 2020.

U. S. Agency for International Development Emerging Threats Program launched the infectious disease surveillance program PREDICT in 2009. It included teams from more than 60 countries that would survey the world for unknown viruses in animals and assess their risk of causing pandemics. The program regularly suffered funding cuts and the insurmountable task of identifying thousands upon thousands of virus species. Virologists estimate at least 600,000 viruses can spillover into humans. Bat coronaviruses, the most expected time bombs, alone number 5,000.

In September 2019, USAID ended funding for the program. It cost $200 million over a decade. Compare that to the trillions the world has lost over a few weeks of a pandemic. Early in the pandemic, researchers used information from PREDICT-funded to classify, isolate, and globally-distribute data of SARS-CoV-2 in absence of samples and government cooperation from China and the WHO.

“We are in an era now of chronic emergency. Diseases are more likely to travel further and faster than before, which means we must be faster in our responses. It needs investments, change in human behavior, and it means we must listen to people at community levels.”

Brian Bird, research virologist, University of California, Davis School of Veterinary Medicine One Health Institute

Disease researchers travel to expected spillover locations like recently deforested areas, exposed mines, wet and bushmeat markets, and farms near these areas. They sample common host and intermediate species like monkeys, bats, and rats, and analyze the surface of the viruses for structures that might fit like a key to human cells.

How the Smithsonian’s National Zoo and other partners in One Health investigate wildlife for pandemic potential.

Researchers also look at cultural activities that decrease the risk of outbreaks. For instance, completely banning wet markets will likely lead to more direct sales to restaurants and create black markets with even less regard for records, crowding, and hygiene. Governments could enforce the separation of animals, limit the distance animals can be shipped, and proper containment during travel.

Poor travel containment is another plausible explanation for why the current pandemic had 13 of the first official 41 cases with no ties to the local wet market, and the first was of those 13 and hospitalized a week before the others. However, law enforcement will likely fail in poor regions.

“These markets are essential sources of food for hundreds of millions of poor people, and getting rid of them is impossible.”

Delia Grace, senior epidemiologist and veterinarian, International Livestock Research Institute in Nairobi, Kenya

Global supply and demand influence the high-risk zones for pandemics. Many developing regions compromised their self-sufficiency in favor of massive monocultures for exports. Natural resources used in the developed world degrade the developing world’s environment. Some people believe that wild animals have medicinal properties. These customers encourage bushmeat sales in regions, particularly cities, far from the animals’ native range. Poaching often accompanies the industry. Corporations moved manufacturing to these already high-risk outbreak regions and worsened local sanitation and increased urban density. Problems that scientists, environmentalists, and philanthropists have called out for decades also increase the risks of disease outbreaks.

Many of the high-risk countries also have corrupt governments and poor scientific infrastructure that make detection and reporting unreliable. Some of these regions also give vague diagnoses and treatment with broad-spectrum antibiotics rather than investigating infections. Programs like PREDICT also had little communication with local hospitals.

“We must think about global biosecurity, find the weak points and bolster the provision of health care in developing countries. Otherwise, we can expect more of the same.”

Kate Jones, chair of ecology and biodiversity, University College London

PREDICT’s old partners have continued their work. Health and veterinary companies, ecology departments and veterinary schools, research institutes and natural history museums, and federal agencies contribute to the EcoHealth Alliance in some form. Global Virome Project worked closest with PREDICT and communicates more with international partners. Founded in 2016, it has an annual $400 million budget and PREDICT’s intensive sampling in the field and genetic sequencing in the lab.

PREDICT might also have a successor called Stop Spillovers, though it would have to start over many investigations and no one has announced a budget.

These groups have several limitations to overcome before they are effective. Besides the given financial problem, public health workers and research ecologists lack communication. Also, American organizations make up the vast majority of these global efforts. Some other countries probably have their own networks, but that still shows that current pandemic prevention is decentralized, uneven between countries, and lacking in communication.

Still, compared to J. S. Koen’s day one hundred years ago, we have ridden quite the learning curve in viral ecology.

EcoHealth Alliance trailer.

Feature image: Once-active PREDICT regions. Crowded Makola Market, Accra, Ghana. Photo courtesy of Erin Johnson.


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