Yellow Springs’ own ‘Cassandra’: An interview with Dr. Allen Hunt
- Published: June 13, 2020
Interviews in this series
This week, the News published an article reviewing the last three months of the coronavirus pandemic, “A closer look at COVID’s first wave.” According to the latest statewide data, COVID-19 cases and deaths have peaked in Ohio are on a slow decline. In addition, Greene County seems to have fared relatively well so far, with a lower per capita case rate than the state average.
However, Ohio Governor Mike DeWine shared new information at his press briefing on Thursday, showing that the virus is spreading more quickly in the Dayton area, with a reproduction rate (R0) of 1.07, than anywhere else in the state.
Also at the briefing, DeWine said that there are no longer any restrictions on test availability in the state and that anyone who wants a test can now get a test, “even if you’re low risk and not showing symptoms.” (Find a test location here.) and Dr. Amy Acton resigned from her post as director of the Ohio Department of Health but will continue to advise DeWine on the coronavirus and other public health issues.
Earlier this week, I spoke with local physicist Dr. Allen Hunt, who has published research in the field of epidemiology, along with a wide variety of fields from climate to geophysics. A professor of earth and environmental sciences at Wright State University since 2007, Hunt was formerly a Fulbright Scholar and also worked at the National Science Foundation. He was among the earliest to sound the warning of the impending pandemic in a letter-to-the-editor to the News in January.
In our interview, Dr. Hunt addressed a newly released study showing that the shutdowns prevented 60 million coronavirus infections in the U.S. (in addition, if the U.S. shut down one week earlier, 36,000 lives could have been saved.) He talks about his projections for a second wave, a potential vaccine and the problem with waiting for “herd immunity.”
The interview was edited for length and clarity.
Yellow Springs News: So, you were talking about the coronavirus pandemic and its impending impact on the U.S. pretty much before anyone else. What were you seeing that so many people, even those in our own government, weren’t?
Dr. Hunt: It was because of preliminary data coming out of China by late January. The case fatality rate, or cfr, was 2% and the reproduction number [R0] was at least 2.5. R0 is a measure of how many others one person with the illness infects. When I compared the R0 value with the flu, a little above one in winter, and the case fatality rate with that of the flu, which is about 0.1%, I became alarmed. I’ve done scientific research in the field of epidemiology. In 2014, I started compiling data daily on the West African [ebola] epidemic. In that epidemic, the number was doubling every 21 days. In China, the number of people infected increased by a factor 10 every 8 days! The article I wrote was published in Complexity. I figured out the case fatality rate and the doubling time before the WHO and CDC. An article in Science recently referred to that article because I showed that not only can you get an exponential increase in the number of cases when you have no intervention, but also when the intervention ramps up proportionally to how many cases you have; if you can only trace and isolate half the individuals exposed by an ill person, it would bring R0 from 2.5 to 1.75, but any R0 greater than one is exponential.
Yellow Springs News: So what are your thoughts on the reopening that is happening now in Ohio and other states? Are we moving too fast?
Dr. Hunt: We should stay somewhere between two extremes. The extremes are going back to business as usual, or a complete shutdown. Where exactly we stay between those two extremes will have to take into account careful observation, data collection and analysis by comparison of the models.
The study claims with modeling that the shutdown prevented 60 million cases in two months. That level of infections would have at least doubled the normal case fatality rate of between 0.7% and 1.4%, and would have meant — with 20% of the cases serious or critical — 12 million hospitalizations and several million ICU admissions. There are probably not that many ICU beds in this country, or even the world. We would have had already at least one million fatalities without the interventions. That tells you how important they were. Mathematics of epidemiology is like interest on a bank account. 5% interest over a year is like an R0 of about 1.001 where your money doubles every 14 years. It was taking eight days for cases to go up by a factor of 10. That’s why I wanted to help; if we waited another eight days until shutting down, we would have had 10 times as many deaths.
It is true, however, that this is an ongoing epidemic and you can’t do controlled studies to determine how much anything you do impacts the reproduction number. You can do comparisons across states, times, and cultures. As time goes on, the predictions get better. The main ways to reduce R0 are with testing and contact tracing or with social distancing.
Contact tracing only works if when you test somebody, you get in touch with them and you check everybody that that person’s been in contact with. You have to follow that up with isolation. Testing is still below what we need. But we have the advantage that our governor was early. As a consequence, we have fewer cases. Because of fewer cases, we can get by with fewer tests. Our numbers seem to be going down again.
Yellow Springs News: What did you think about the original modeling? Was it too optimistic or pessimistic?
Dr. Hunt: The [Institute for Health Metrics and Evaluation] were way off, they said only 60,000 deaths by August. At the end of April it was obvious that there would be 100,000 by the end of May. They do point out something that’s extremely important and that is that we have many more cases than we are aware of and as the testing goes up, you find more cases. And as a consequence, even though the number of people being infected may be dropping rapidly, you’re still finding 20,000 new cases a day. Though we are still finding 20,000 new cases per day, the fatalities have dropped to under 1,000 per day. The two reasons for that are, there are fewer people altogether getting infected and we are testing more people who did not have symptoms.
The reason the reopening scares me is that part of the decision is made on an economic basis. If you make it based upon an economics where you will run out of money due to unemployment, you are not making the decision based solely on epidemiological models. This is a problem because the U.S. Senate would not agree on a second bailout of the states. I believe all the states are rushing things a little bit. The University of Washington model suggests we’ll have a slow decline through about August, with potential increases after that. Then the kind of decision being made is one that works if the model is actually overestimating the danger, but will get us in trouble if we are underestimating it.*
Yellow Springs News: Greene County Public Health officials have said they have been able to do contract tracing from the beginning of the crisis. Does that give you some comfort?
Dr. Hunt: Yes, and I think it’s good that we have a competent public health system. But it’s very important that we have a national policy on this. Ohio, Kentucky and Indiana are closely linked. If one of us has sufficient social distancing but the others don’t, we have a problem. We can import more cases.
Yellow Springs News: There is a lot of talk about a possible “second wave” coming in the fall. Do you think that is possible, and can you speak about the timing?
Dr. Hunt: It’s possible to not have a second wave. It’s also possible to have a second wave in June, and then another in August and in November. There is no evidence whatsoever that it is seasonal. There is no comparison to the flu in that regard. Flu and more traditional coronaviruses have been around for many hundreds of years, and as a consequence, people and the virus have co-evolved to be at a very near equilibrium. There are some factors such as the fact the virus lives longer on cold, dry surfaces, that people spend less time out-of-doors, etc. These small changes can change the reproduction number between 0.9, in summer, and 1.1, in winter. The problem here is we actually have a reproduction number of 3.5 [for the coronavirus] without social distancing. If you make little changes, it doesn’t matter much. We are still desperately susceptible to it. There is no hope of a seasonal advantage. What is keeping our transmission low enough now is the intense social distancing, and if we let up too much, the number will rise. The differences is we’ll be starting out with 20,000 known cases per day rather than 100 known cases per day in early March. But nobody knows for sure what too much relaxation is.
Yellow Springs News: So what can we do to prevent future waves?
Dr. Hunt: What other people say — staying away from each other, six feet minimum in open spaces. But whether adequate distancing can be done at work is highly heterogeneous. While some people can distance, especially those who are retired, or work at home, we can only protect ourselves if we have that option. It all depends upon what everybody else is doing. Some social distancing will be maintained if the economy opens up, but I’m seeing a lot of people who don’t do it. That turns out to be okay right now because we have so few cases in Greene County, but that won’t be okay where the reproduction number is already close to 1.0 and where the number of cases is still high.
The question is, do we have the government will to keep track and react accordingly? If we’ve got to clamp down again, will they do it? And will the federal government put in the money on an ongoing basis? If so, we can get along in the next year or so until the vaccine is, hopefully, developed, with on the order of 100 to 500 deaths per day, 15,000 per month, for 12 months. That would be up to 180,000 deaths, so 300,000 deaths total. That’s bad but it’s not three million deaths, which is the potential.
Yellow Springs News: Can you speak more about the issues around vaccine development? When can we expert it?
Dr. Hunt: How do you figure out when the vaccine is coming? There is no way except to listen to people like [Dr. Anthony] Fauci. He says as soon as early next year, but other experts consider that too optimistic. The problem is that we just had a period of weeks where we did not hear from Fauci at all. Why is he now so much more optimistic? What we have is a situation where the fastest vaccine against a virus, an RNA virus, was four years, for the mumps. That’s the record. We have about seven of those vaccines. But we also have an incredible transmission of scientific data, we have tools that no one had before, like gene sequencing and editing. But there are so many things that can still go wrong.
Yellow Springs News: What about those who say we should let it run through the population to develop herd immunity?
Dr. Hunt: No one knows how long coronavirus immunity lasts. The evidence from other coronaviruses is you can pick them up every year. So immunity lasts, at most, a year. You can go through herd immunity once, then you have to do it again next year. Maybe there is some element of immunity that remains, and the second time, maybe 80% or 90% doesn’t get it. That would be lucky.
The basic point is that herd immunity is not something to want to develop first. We have 20,000 new cases per day, there might be 20 million who have been infected. In that case we will need 10 times more infected people to develop herd immunity. Even at a slow pace, that would take one million deaths.
But with 60 million cases by the end of the May, you could have four million deaths because of exceeding hospital capacity. That kind of calamity produces an economic catastrophe way beyond what we’ve seen. Instead, if you spread them over a year or two, or five years, it’s better, because then you might get a vaccine, though you might still have to administer it every year. You can’t predict the future, but we can’t be under 100,000 deaths anymore. That’s passed. We could have kept it under 100,000, and all we would have had to do is act one week earlier. With the same social distancing level, we would now be seeing 2,000 cases per day nationwide per day and not 20,000. This is why the government should act swiftly and resolutely when the alarm bells are all ringing with the epidemiologists.
*After the interview, Dr. Hunt sent the following email update related to his comments about some states opening too rapidly:
California, Texas, South Carolina, Arizona, and Utah all had their highest number of new COVID cases yesterday [June 9.] Florida did on Thursday. Wednesday, Thursday, and Friday saw three of the five largest new cases in Florida up to now. California is similar, having broken its record twice in the last week or less.
[President] Trump and the stock market have effectively declared the pandemic over, but it requires the mask, distancing, and adequate testing. How well are we doing on those? Time and statistics will tell…it only takes one sick customer without a mask and dozens can be exposed. Then the cat is out of the bag again.
Read about the spike of cases in some states this week in the Washington Post.