Huffington Foundation Professor in the College of the Environment Fred Cohan studies the origins and diversity of bacteria, and is currently in the process of writing a book based on his favorite course: “Global Changes and Infectious Diseases.” In February of 2020, he wrote an article in the Conversation about the novel coronavirus disease (COVID-19), and the clue to stopping it. In March of 2020, Cohan posted a letter urging students to support the shutdown to keep our communities safe in response to the Wesleying article against University closure. The Argus followed up with him to discuss the origin of the virus, his connection to the infectious diseases, and the ways to stop the spread.

 

The Argus: I know you said you couldn’t really give advice, so I was hoping to get more of a biological perspective. What is the coronavirus, where did it come from?

Professor Fred Cohan: Well, this coronavirus, like pretty much any emerging pathogen that comes into humanity from nowhere apparently, is actually coming from a wild species of animal. And bats, unfortunately, have been the perpetrator of almost all of the recent emerging infections. So we go back a little bit, and we have two other coronaviruses that have come to humanity and they’ve both come either directly or indirectly from bats. But anyways, it appears to have come to us from a bat species in China, which kind of makes sense because it was in China that humans got first exposed to it. These emerging viruses are almost entirely spillovers, that is infections that are passed from another species to another. 

A: Is it an RNA virus or a DNA virus and if so, how is it transmitted?

FC: All of the coronaviruses, that family, are RNA viruses. Almost all of the viruses that infect humans are RNA viruses. Exceptions are HIV—it is actually a retrovirus which alternates from RNA to DNA to RNA. A couple of examples of DNA viruses are herpes viruses, and smallpox and cowpox and monkeypox and related viruses. So how are they transmitted? I’m not sure exactly how they come out of the bats. It’s mostly a respiratory virus in humans, but in humans it does get into the gut and if it were to get to the gut of bats, it would probably be passed through their feces. And that might be how we got it. There’s not really a lot of information about how we got it from the bat. I assume it’s from poops. Have you seen the movie “Contagion?”

A: No, my family recommended I watch it now though!

FC: Highly recommend it. It came out in 2011, and what I like about it is it gives an entirely plausible scenario of how we got this particular virus in the movie from bats, which is pretty pretty similar to how we got other things. In these wild animal markets, these different species of animals are kept one cage on top of another on top of another. So the feces of one could just move on down to another. And if there are bats in the area—which is not unlikely as there’s also food in these markets—and if the bat defecates on top of the cage another animal could eat the feces along with the food that its caretaker is giving it. 

A: To your understanding, how does the test for the coronavirus work?

FC: It’s a PCR [polymerase chain reaction] test. I don’t know more about it than that. 

A: Many people have been relating this to the flu, and saying that as it gets warmer it may disappear. Could you touch on that, and if it’s realistic?

FC: I’ll tell you one thing. Anthony Fauci, who is the director of one of the National Institutes of Health [NIH], which is the National Institute of Allergies and Infectious Diseases [NIAID], no one can pin him down as to whether this will kind of fade out in the warmer months because we don’t know this virus. But the one thing I can tell you is that it’s transmitting just fine in Australia, which is having summer now. I’m not all that hopeful, but honestly I have not heard comparisons of the transmission rates between the Northern Hemisphere and Southern Hemisphere right now. Maybe the R0 [a statistic scientists use to measure the average number of people each contagious person infects] is lower in Australia. I just haven’t seen that yet.

A: I read your article featured in the Wesleyan Connection from early February, and it seemed like back then you had an idea about what could happen with the coronavirus. Do you think that epidemiologists are surprised at how bad it is getting or figured it might happen?

FC: So this disease was named before it was even in humans. It had a disease called Disease X. And virologists who study emerging diseases knew that there had to be another emerging infection and reserved the name Disease X for that virus in the future that would have all the properties of this one. It transmits easily, it transmits asymptomatically, it’s confused with other diseases, you don’t really know that you have it. People knew that there was this thing coming, and they named it Disease X. I want to tell you something about this global virology program that’s been set up to anticipate this and anticipate viruses in the future, if you want to hear about it.

A: For sure. 

FC: There’s a thing that was proposed and it’s an informal consortium of scientists called the Global Virome Project. What this project aims to do is to discover, characterize, and genome sequence every virus on the entire planet that could possibly infect humans. And that’s a really ambitious project, though what makes it kind of manageable is that we know those virus families that have infected humans. And we know those orders of mammals, of birds that have been most likely to transmit their viruses to humans. So those are the orders of bats, primates, rodents, and artiodactyls [cloven-hoofed mammals]. Mostly the ungulates that we use for food: cattle and camels and so on. So they’re doing this, they’re out on the prowl in the jungles and deserts wherever, to try and sample the saliva, the feces, whatever, of wild animals of the right mammalian orders and just checking for viruses. They’ve done all sorts of clever things, like they’ll put some sort of candy on a string and an animal will eat it and then salivate on it and they can find out what species it was from the saliva. They can also sequence the virus. So things like that that you could do to find out about viruses that you’ve never even seen. 

A: I should have asked this earlier, but what is your connection to virology and the coronavirus? 

FC: There are two connections. One is the connection to the theory that we’ve developed about how to discover newly divergent species of microbes. And we’ve been doing that with bacteria for decades, and we just recently started doing that with viruses. The other connection is that, for the last decade or so, I’ve been teaching “Global Change and Infectious Disease,” and it’s become my favorite course to teach. I feel like every year becomes more and more important to get this information out there. I’m writing a book that’s based on the course, and every year I teach it, I give the students a draft of chapters as far as I’ve gone. I’ve learned a lot about this, and I’ve kind of reviewed the ethics that are important in the age of pandemics. It’s important to contribute both a biological and ethical point of view from the studies that I’ve done to prepare for the course.

A: When you say we, do you mean your lab at Wesleyan? 

FC: Yes. There’s actually two projects I’m working on now, they’re both with my students at Wesleyan. One is the “Global Virome” part that deals with ecological diversity…. But what I’ve been doing on my own is really working on the book, and trying to work out—basically what the course and the book are about is all the ways that the demands that we put on the environment have come back to bite us in giving us infections. The demand we put on the environment is in categories of procuring food, using land, transport, travel—so energy in the case of global warming, and healthcare in the case of antibiotics. So the book is all about that, and how all those things contribute to diseases, emerging diseases and why it is that we really have this unending parade of new plagues. And then I have a whole chapter on what we should be doing to prevent this from happening. I’m very excited about trying to help in the fight against this coronavirus, and helping our students understand it better.

A: What exactly are you doing to educate students and help with the fight? 

FC: I’ve written a couple op-eds that deal with this. So there’s an op-ed that I wrote…that dealt with how fear of infections might be the gateway to making us all environmentalists. The idea is that the ways that we disturb the environment give us new infections, so maybe if we could understand that we could kind of renew our enthusiasm for environmental protection that was such a big deal earlier in my lifetime. I think that putting in the connection to infections will make us all sensitive to the need to lessen our impact on the environment. In fact, it’s so true right now. It’s applicable in the case of the new coronavirus because this comes out of, presumably, our bushmeat hunting. Our hunting of wild animals, trading animals. If there hadn’t been that wild animal market, there wouldn’t have been that opportunity for bats to pass on their diseases by way of the animals that we’re buying. I’ll just mention one thing that upsets me a lot—in contrast to the case of SARS, back in 2003, the Chinese government unfortunately destroyed all the forensic evidence from that animal market in Wuhan. So we really don’t know, in fact we’ll probably never know, who the intermediate animal species was. Because it’s not something that’s out there in some other species because it was just the individual animals that were there at the market and exposed, for all we know. It’s all a mystery.

A: So just to clarify, you think this is something connected to human actions?

FC: Right, that’s the important thing. To give you an example…there’s another article I want to point you that I published in the Arcadia, Wesleyan’s political review. I wrote a pretty long piece called something like, ‘what we can all do to fight disease.’ And it really looks at the really big picture. 

A: In your opinion, what do we need to do to limit the spread?

FC: We need to first off, keep our germs to ourselves. And this is something that has changed a lot. [Before], the typical apple vendor, street vendor, would spit on their apple and polish it with their hands. That is now seen as totally disgusting, and any vendor who does that will be seen as a pariah. Our ethics and expectations of people we do business with totally changed over time. 

So this is the business of keeping our germs to ourselves—and social distancing is part of that, of course. If we should be exhaling and expelling viruses unknowingly, we can at least be sure we’re not going to infect anybody. 

The next thing was keeping ourselves healthy. If we are not infected, we cannot infect somebody else. That is kind of a public responsibility, to look out for ourselves and make sure we don’t become sick. So this hunkering down thing is actually a big part of that. So those are the first two points.

Then after that is the socialism of the microbe idea, which actually has three levels. The original meaning of the socialism of the microbe was invented at the turn of the 20th century, early on in the germ theory era of disease. What people meant by that at the time is that we must care for others that are infected, or else their infections will become ours. And that was really a big part of the inspiration of the progressive movement in the early 20th century where people realized TB was an infection of poverty—so people asked, what do we need to do? We need to fight poverty and we will thereby prevent tuberculosis. When we do that, we and our families become less likely to become infected. So it’s not just altruism, it’s an altruism that has a payback to keeping us healthy. That’s kind of the traditional socialism of the microbe. What I’ve been thinking about is how to extend that idea, what are the other ways that we should be making investments and sacrifices for other people’s health, that will come back to benefit us. 

One idea has to do with contributing to the public health of other countries that are too poor to take care of themselves. In this regard, there is a lot of worry about what’s going to happen when the coronavirus reaches the poorest countries of Sub-Saharan Africa. We don’t want these countries to be an amplifier of the disease. In my mind, it would clearly benefit all of us if we could stop that from happening. And more generally, I think that we can invest in public water supply, that will also be something that will come back to help us. For example, if we’re dealing with a poorer country that at least has some regions in it that don’t have secure water, that means there will be a lot of fecal-oral transmissions going on of salmonella, E.coli, cholera, and such. The problem with a lot of sick days [for those people], and that’s an awful thing. But it’s also beneficial for us to help the people in other countries develop their public health infrastructures because what happens is, when people get sick from an antibacterial infection, they’ll take antibiotics which will add to the worldwide burden of antibiotic resistance and that will tend to give us, in the developed world, superbugs that we can’t control. 

Finally, the last part of the socialism of the microbe is that we need to invest in environmental protection, here and elsewhere, so that it becomes less likely that there will be emerging viruses coming out of nature. We talked about forest fragmentation and bushmeat hunting and so on. Those are things we should invest in trying to prevent and will make it much less likely to have to suffer from a pandemic in the future. 

 

Hannah Docter-Loeb can be reached at hdocterloeb@wesleyan.edu.