Infection of Wildlife Biologist Highlights Risks of Virus Hunting

Infection of Wildlife Biologist Highlights Risks of Virus Hunting

The illness was mysterious. A 25-year-old graduate student had been hospitalized with a high fever, muscle and joint pain, a stiff neck, fatigue, sores in her throat, and a metallic taste in her mouth. She soon developed an angry rash. To make the diagnosis, her doctors had an important data point to consider: Days earlier, the woman had returned to the United States from a field expedition in South Sudan and Uganda, where she had been capturing and collecting the blood and tissue of bats and rodents. That information proved critical — and is newly relevant given concerns that the pandemic may have come from a research accident. Three days after she was admitted to the hospital in 2012, tests determined that the student was infected with a novel virus that infects a type of fruit bat that lives in the rural areas of Uganda.

The graduate student recovered and left the hospital two weeks later. But the incident, which was written up in the journal Emerging Infectious Diseases in 2014, proved scientifically important. Not only did it allow for the identification of the Sosuga virus — a paramyxovirus named for Southern Sudan and Uganda — and the knowledge that the bat virus can infect and sicken people, the woman’s infection also pointed to the dangers posed by the kind of research she was doing: trapping, manipulating, and dissecting animals suspected of being infected with novel disease-causing viruses.

Biosafety experts have long worried over the possibility that scientists seeking dangerous viruses in the wild could inadvertently become infected in the course of either capturing or coming into contact with the saliva, urine, or feces of the animals. The case of the Sosuga virus shows that those concerns are well founded.

Virus hunter Michael Callahan, an infectious disease doctor who has worked for federal agencies on global disease outbreak and the tracking of wildlife pathogens, has vividly described the high risks faced by field researchers. “Squirming, clawed and toothy animals bite and scratch during collection of body fluids. Teeth and talons easily penetrate the thin gloves required to maintain dexterity when handling fragile wildlife,” he wrote in Politico in 2021. “The fact that researchers are not infected every time they do a field collection is a question that continues to stump us.”

With more than 6 million people now dead from Covid-19, the catastrophic potential of a researcher becoming infected with a wildlife pathogen has become inescapable. While the origins of the current pandemic are still unclear, it remains possible that virus hunting could have been the cause. Rocco Casagrande, a biochemist who was hired by the National Institutes of Health’s Office of Science Policy to assess the risks of gain-of-function research, thinks a natural spillover of the virus from animals to people, a lab accident, or what he calls a “prospecting based accident” are equally likely potential causes of the initial outbreak. He imagined the prospecting scenario as “the researchers in Wuhan looking for bat viruses found one and got infected outside of the lab.”

Even as the very real chance remains that the search for new viruses led to this cataclysmic event, scientists hoping to prevent viral outbreaks continue to seek out new bat coronaviruses and other potential pandemic pathogens around the world.

Ask the Bats

The search for pathogens that infect animals is driven by the desire to prevent and prepare for their possible transmission to people. But that work, which spans the globe and is funded in large part by the U.S. government, can sometimes result in human infection — exactly the outcome it is meant to prevent.

Virus hunting — or wildlife disease ecology, as DeeAnn Reeder prefers to call it — is a field that has come under increasing scrutiny during the Covid pandemic. For Reeder, a professor of biology at Bucknell College who led the 2012 expedition on which the graduate student was infected, one of the central purposes of her research in Africa on bats’ immune responses to viruses is to understand how humans might react to the same infectious agents, knowledge she says can protect us if the pathogens jump from animals to humans. “If you want to understand how to survive a coronavirus, or if you want to understand how to survive a filovirus — Ebola fits within that context — you need to ask the bats because they know how to do it,” said Reeder.

Reeder, who put up her first bat net in South Sudan in 2008, continues to do wildlife research in Uganda. No one has previously reported her connection to the work. “I’ve never been contacted by a reporter on that particular story,” Reeder said, after being asked whether the Sosuga virus infection occurred during research on one of her projects. “I’ve always been surprised about that.” Reeder would not confirm the identity of the researcher on her project who was sickened, citing privacy concerns.

The Sosuga case shows that concerns about viral transmission from wild animals to researchers are not just theoretical. It is still unclear exactly how the infection occurred. While the graduate student only occasionally used protective gear when working with animal specimens, when she visited the bat caves she wore a paper Tyvek suit that’s become the hallmark of virus hunters, gum boots, bite-resistant gloves, and even an air-powered respirator known as a PAPR that looks like an astronaut’s helmet. The researcher did not report being bitten or scratched by any of the animals she encountered.

“Maybe outside the cave before they put the respirators on, she leaned against a rock that had been peed on, because we know that it could be in the kidneys of this particular bat species,” said Reeder. “But that’s just conjecture, which is the scary part.”

CDC scientists approach Bat Cave in Queen Elizabeth National Park on August 25, 2018, Uganda.

CDC scientists approach Bat Cave in Queen Elizabeth National Park on Aug. 25, 2018, in Uganda.

Photo: Bonnie Jo Mount/The Washington Post via Getty Images

Cowboys and Cowgirls

Reeder carries a card in her wallet she hopes medical professionals will read should she herself wind up in the emergency room with a mysterious infectious disease someday. “It says, ‘Attention medical personnel: I study wildlife disease. Here’s all the things you should test me for should I present to you in the emergency room,’” she explained.

Reeder describes herself and other researchers in her field as “a little bit like cowboys and cowgirls — we go to a foreign place and we catch exotic things.” Yet she’s grown increasingly cautious during her years in the field. “When I first started this work, nobody was wearing PPE. It just wasn’t a thing,” she said. “I thought we were good if I didn’t have my coffee cup on the same table when I was doing dissections.”

Despite her growing concern about biosafety, Reeder has still had a few worrisome interactions with bats herself. “I had one bite me. That big canine tooth went right into my knuckle, and for like two years, whenever it was cold, my knuckle would hurt,” she recently recalled. And in 2017, Reeder was stuck with a needle that had just come out of a bat that she knew could have carried the deadly Ebola virus.

“I was like, wow, OK. So I make notes in my notebook, started counting 21 days, which is the incubation period for Ebola,” said Reeder. “I’m mostly kind of flippant about that. But I can tell you I knew when that 21 days was up.”

Yet even after these experiences, Reeder said there are rare times when she still eschews personal protective equipment: “If I’ve got a live bat, I can’t go into a village and show up in my space suit.”

Most interactions with bats don’t cause disease. But the risk of viral infections remains — and many professional scientists and hobbyists don’t even take the basic precautions to protect themselves from it, according to a study published in 2021 in Biodiversity Data. The authors, who include Reeder, analyzed 759 of the more than 43,000 photos of people holding bats taken that were uploaded since the 1980s to iNaturalist, a popular biodiversity tracking app. While the percentage of the app’s users who wore gloves when they held bats has increased over time, even in 2021, less than half of the people holding bats, both dead and live, were wearing gloves.

“This lack of adherence to even minimal biosafety practices may jeopardize both the safety of the bat and the handler,” the authors concluded.

Reeder said those who continue to openly flout the recommendations to wear protective gear are increasingly met with disapproval within her scientific community. “If somebody is at a conference and they show pictures of themselves in the field not wearing a face mask, and not wearing gloves, even latex gloves, there’s a little bit of criticism,” she said. “A sort of public shaming.”

Ongoing Risk

As a recent report from the World Health Organization makes clear, there is still no definitive proof of how Covid-19 originated. And an infection that occurred during the collection of dangerous new coronaviruses from bats is among the possible explanations for the initial coronavirus outbreak in Wuhan in 2019. There is no question that the National Institutes of Health, which indirectly funded bat coronavirus research at the Wuhan Institute of Virology in China, is still struggling to fully understand the biosafety precautions taken around that research. Yet the U.S. government continues to support similar research around the world, with grants to numerous organizations including EcoHealth Alliance, the NIH grantee that worked with the Wuhan institute.

EcoHealth Alliance, a nonprofit research group based in New York, received a $3.1 million grant in 2014 from the NIH, some of which was spent on the collection of novel bat coronaviruses in rural China. Specifically, the organization awarded a subgrant of some $750,00 to researchers at the Wuhan Institute of Virology. In April 2020, at the request of President Donald Trump, the NIH suspended that grant. But four months later, the NIH awarded EcoHealth Alliance another, larger grant. (The Intercept obtained the grant documents via a Freedom of Information Act lawsuit with the NIH.)

Like the first grant, the second grant — titled “Understanding the Risk of Zoonotic Virus Emergence in Emerging Infectious Disease Hotspots of Southeast Asia” — pays for the collection of what it calls “high zoonotic potential viruses” from remote locations in Southeast Asia. It also funds experiments involving the infection of humanized mice with hybrid viruses created from the new viruses, which are designed to gauge the threat those viruses pose to humans. The grant is funded through 2025.

Other branches of the U.S. government also continue to fund the collection and study of novel viruses that could infect humans, including DEEP VZN, a $125 million project funded by the U.S. Agency for International Development, and the Ecology and Evolution of Infectious Diseases Program, which is jointly funded by NIH, the U.S. Department of Agriculture, and the National Science Foundation.

“Everybody has been just kind of winging it.”

Despite concerns about biosafety lapses in U.S.-funded research in Wuhan and a lack of oversight from both NIH and EcoHealth Alliance, there are no agreed-upon standards for ensuring the safety of ongoing research.

“There is currently very little biosafety guidance specifically for this kind of biological fieldwork,” Filippa Lentzos, a biosecurity expert who works at King’s College London, wrote in an email to The Intercept. “This is a major gap in biorisk management that urgently needs to be addresses both nationally and internationally, not least because this kind of fieldwork is on the rise.”

During the pandemic, David Gillum, assistant vice president for environmental health and safety at Arizona State University, began meeting with a small group of experts over Zoom to discuss biosafety practices for researchers working with bats in the wild. “It’s guidance on what to wear as personal protective equipment, what vaccinations should you have before you go to a certain area, what medications should you bring,” said Gillum. The group’s recommendations are expected to published soon in the journal Applied Biosafety. Up until now, he said, “Everybody has been just kind of winging it.”

While Gillum and other biosafety experts say they hope national and international field work guidelines will ultimately be put in place, they expect the process to take years.

In the absence of such clear recommendations — and with institutions coming up with their own varied approaches to biosafety — a range of researchers face the risk of infection from pathogens in wildlife, according to Casagrande, the biochemist. “And that includes people specifically trying to find viruses but also people who aren’t,” he said. “Plenty of biologists who work with wildlife also don’t take precautions. And many times they get infected by things.”

Researchers, from the Thai Red Cross Emerging Infectious Diseases Health Science Center, take a saliva swab from a bat caught at Khao Chong Pran Cave, inside a makeshift lab set up nearby during a catch and release program in Photharam, Ratchaburi Province, Thailand, on Dec. 11, 2020.

Researchers from the Thai Red Cross Emerging Infectious Diseases Health Science Center take a saliva swab from a bat caught at Khao Chong Pran Cave, inside a makeshift lab set up nearby during a catch and release program in Photharam, Thailand, on Dec. 11, 2020.

Photo: Andre Malerba/Bloomberg via Getty Images

A Fine Balance

While the pandemic has sparked a debate about the safety of studying dangerous viruses, most scientists agree on the need for at least some viral surveillance. To Reeder, the emergence of SARS-CoV-2 has made the value of her work only clearer. “Our understanding of the extraordinary diversity of SARS-related coronaviruses in bats in Southeast Asia is really critical for our pandemic preparedness, for our ability to predict what’s going to bind to human receptors,” she said. “We need to understand what’s there.”

As she sees it, that benefit is worth whatever risk it entails. And, in the case of the graduate student infected with the Sosuga virus, the cost wasn’t great. The virus didn’t kill her — and, critically, it didn’t spread from her to other people. Looking ahead, Reeder said, improved adherence to protective gear should protect against future viral jumps from animals to researchers.

“I think you just do your best, right?” said Reeder. “You try to look for those gaps. You put your gloves on, then you put your Tyvek suit on over those, and then you take Gorilla tape, and you wrap your wrist with Gorilla tape to make sure that you don’t have a gap as you move your arms,” she said, noting that colleagues in the field tend to help one another. “You can call each other out on stuff. You know, ‘Hey, it looks like your mask has slipped.’ But it’s never perfect, and this case just sort of illustrates that for us.”

The case of the woman who was infected working with bats in Uganda also taught Reeder how, at least that time, luck was on her side: “This could have been really, really ugly.”

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