Chris Woods has spent decades studying infectious diseases — how to diagnose them, how to treat them, and how to predict who’s going to become infected. Now the Duke professor of medicine and global health is putting that knowledge and experience into answering those same questions about the new coronavirus and the COVID-19 illness it causes.
When the pandemic first erupted earlier this year, Woods, who is also co-director of Duke’s Hubert-Yeargan Center for Global Health, spent a lot of time coordinating and training teams of scientists to work with the wily and sometimes deadly coronavirus. They began collecting samples from a group of infected Duke students who had just returned from traveling abroad. In the last couple of weeks, Woods has shifted his focus to generating and analyzing data that will help increase an understanding of how the virus acts in different populations around the globe.
He says one of his biggest goals is to develop diagnostic tests for COVID-19 and other diseases like it.
“We’ve been interested in emerging infectious respiratory diseases in particular for several years and have been working on coming up with better diagnostics,” he says.
Woods, a medical microbiologist and clinical infectious diseases physician by training, spent a chunk of his early career as a Centers for Disease Control and Prevention epidemiologist. He comes at the pandemic with what he calls “an outbreak response approach” that brings together his clinical and laboratory perspectives. But he’s also relying on the knowledge of scientists with other types of expertise, including colleagues at the Department of Medicine’s Center for Applied Genomics and Precision Medicine and the Duke Human Vaccine Institute.
Woods says that one of the trickiest things about studying viruses is that they’re not like other pathogens, or each other.
“We respond differently to influenza than how we respond to this new coronavirus compared to how we respond to the common cold virus,” he says.
To figure out those distinctions, he and colleagues have set up studies in a couple of different ways.
“The first way is by evaluating humans’ basic response to viruses. We’ve been doing that by actually giving virus to people over the years — using human rhinovirus and different strains of influenza,” he says, pointing out that they don’t give people viruses that could be deadly.
This research approach has allowed them to understand the timetable of human response to infection "from inoculation through resolution" and then "harness the human molecular response" to infection to develop diagnostic tests.
From that experience, the team implemented uniquely designed index-cluster studies, conducted on college campuses and in family units, that have helped Woods and his colleagues predict when people are going to get sick — when they’re infected but before they develop symptoms.
“We can do that usually two days before meaningful symptoms come about,” Woods says, noting that they’ve run studies like this in the United States, Sri Lanka, Nicaragua, Kenya and Tanzania, all looking at different populations and how they respond to viruses.
“We’ve made this a very comprehensive program,” he says. One that allows scientists to enroll not just sick people, but also those who are in close contact with them.
Now they’re running a similar study with coronavirus patients in the Duke community with the hope that it will help them figure out how to identify COVID-19 patients before they show symptoms so that they can isolate and avoid infecting others.
“We have been able to enroll 40 subjects in the study who were all part of a large travel group. They had a remarkable attack rate [of COVID-19] in this group,” Woods says.
While most had mild illness, a couple had moderate illness, and only one person required brief hospitalization. It is interesting, Woods says, that among the infected individuals—all young adults—early symptoms really varied, ranging from persistent fever to typical respiratory symptoms to gastrointestinal symptoms.
“Some had a cough, but a cough was not universal and for some it was persistent while for others it was not. I’ve been saying, ‘If you’ve seen one case of COVID-19, you’ve seen one case of COVID-19,’” says Woods.
While the entry funnel is full of variety, once admitted to the hospital, many COVID-19 patients have a more common, similar progress.
His study will act as an umbrella study that will serve as a feeder into other COVID-19 research going on at Duke, such as the work happening with the immunology group and scientists at the Duke Human Vaccine Institute.
“We are sharing special samples, blood cell subsets, and serum samples, to help other researchers further develop their diagnostic assays to create vaccines and therapeutics,” he says.
Part of the reason they’ve had success collecting and studying COVID-19 in the Duke community, says Woods, is that, “everyone is all on board with trying to pursue knowledge here… people have been receptive to helping. We are very thankful to our subjects who’ve been so willing to participate and offer their time.”
In addition to studying how to identify and track COVID-19, Woods hopes they can help find a treatment. One approach is to learn from people who’ve been infected and survived — those who’ve developed an immunity. One theory is that the blood plasma — the liquid part of blood that carries red and white blood cells and platelets through the body — of recovered patients could be used in sick patients, but it’s early yet to know if this will work.
Woods’ work includes more pragmatic tasks, as well, including making sure all regulatory issues are in place: permissions from individuals participating, training on how to put on and take off personal protective equipment, and arranging visits using safe protective practices.
“We’re taking nasopharyngeal, blood, and stool samples, focusing primarily on nasopharyngeal. We also have approval to collect from pets,” he adds.
He is also working on a research program looking at the physiological response to the virus using data collected from wearables, including Fitbits and Apple watches, with colleagues at Duke’s Pratt School of Engineering.
“For me, at the end, it’s not all that different than what we do with influenza. Normally, we work with 20 different pathogens. This makes 21. We’re incorporating COVID-19 research into our current research programs.”
On a personal note
When asked about his own feelings about working with a potentially deadly pathogen, Woods says, “Fear and panic become just as dangerous as the pathogen itself.”
He adds, “Having a good understanding of how infections work in general — even though this specific one is very distinctive — and understanding who’s at risk, that helps me stay sane. That said, we are having a big pollen season and there are days when you wake up stuffy and say, ‘Oh my gosh, is something going on.’”
Woods and his family did have a long conversation early on because they knew theoretically that they were at greater risk for infection due to his COVID-19 work.
“We’re living a relatively normal life,” he says, explaining that he has a very deliberate procedure when he comes back from the field. His clothes go immediately into the laundry, he walks right into a shower on his home’s first floor, and he’s sleeping in a guest room.
Woods also makes time to get out in his yard, where pulling weeds, mulching and enjoying the fresh air help him find balance and a little peace during these uncertain times.