RAPID CITY — With so many questions and debates surrounding the best practices to follow when navigating a world with COVID-19, it can be difficult to know if you are making the right choices to keep yourself, your family, and your community safe. The Pioneer took time to talk again with Dr. Shankar Kurra, vice president of medical affairs with Monument Health, to get back to basics and take a closer look at what this virus does, how our bodies respond to it, what scientists are doing to create a vaccine, and how we should move forward with opening schools in the meantime.
Q. “How do we contract the virus, and what does it do to the body once we do?”
A. “Let’s begin at the basics. The virus is similar to the previous SARS virus in 2003, and it’s very similar to the regular coronavirus that causes just a mild cold so the response to the current coronavirus, SARS CoV-2, is very similar to the first SARS in that the body is able to generate antibodies.
Kurra explained the process by which the human body fights off infectious invaders like coronavirus is two fold. The body’s B-cells produce antibodies to fight the virus, while T-cells help regulate the inflammatory response within the body caused by the internal battle.
“When the vaccine makers make these phase one and phase two trials, what they’re looking for in a response is a measure (of) how effective was the human body (at) mounting an antibody response and a T-cell response. So far, the four vaccine trials that are moving on to phase three have done very well.”
Kurra referred to Moderna and BioNTech, the two vaccine makers that are conducting trials on an RNA-type vaccine for the virus.
“Both of them have shown independently in separate studies that they’re very effective at least in phase two trials. Now what we don’t know is phase three, when they go on to test the vaccine in a larger population beyond the selected 18 to 50 age group. Now they’re going to older and the very young, and that’s where the real results are to be found.
The other two vaccines, one out of Oxford University and one out of China, both are what are called “vector vaccines” and these have also shown that we mount a response. So all of this points to the fact that we can mount a good immune response to coronavirus, the question is will they be able to succeed in making a vaccine that works for the general population. The other question is, ‘how long do these last,’ and the best evidence out there varies. We have a very good case study from the 2003 SARS, that showed a patient still has antibodies to the SARS 17 years later. In fact, they’re using that to make monoclonal antibodies against this SARS, because that’s being shown to be effective. So it just gives you some idea that the time duration is very variable. Some people retain those antibodies for a few months to many months and some people for years, so that’s the part that is unknown.”
Q. “You mentioned Phase one, phase two, phase three trials for vaccines. What are the bench marks for each of those trials?
A. “It’s very straight forward-phase one is basically safety, so you want to have no adverse events. Like any medication you take, the first thing you ask is, ‘what’s the safety profile, what are the side effects, will it kill me, will it destroy my organs,’ that’s phase one. Phase one is usually small (and) quick.
(In) phase two, what they do is take a larger group, usually in a safer age range, 18 to 50 (years old) typically, and then look at, ‘was it safe and is it able to generate effective response’.
Phase three is really where everything is, because you’re testing tens of thousands. Thirty thousand people is what Moderna and BioNTech’s vaccines are enrolling. This is a broad representative spectrum of age groups, races, (etc.). They’re trying to see, ‘can we extrapolate the findings in phase one and phase two truly to a wider population,’ and that’s what phase three is.”
Q. “Have there been any side effects associated with these trials?”
A. “As expected with most of these vaccines, you mount a very low pro-inflammatory response, some mild swelling, some mild fevers, all of those they were able to treat with just plain old medicine (like) Tylenol. Not a single trial participant in any of the phase one/phase two trials in all four of the vaccines had anything amounting to what we’d call serious adverse event.”
Q. “Should a vaccine pass its phase three trial, what kind of time frame could we be looking at for wide distribution?”
A. “Let’s say … the success of these trials were published in peer-reviewed journals and people in the know like virologists, microbiologists, and vaccine scientists look over it and say, ‘yeah, we accept these results,’ … it won’t be earlier than spring of next year, more than likely fall of next year; that’s the fastest.”
Kurra explained that the companies working on the four vaccines are projecting phase three to be published for peer review in September or October of this year. Once those results are studied and confirmed, the broad manufacturing process will need to be worked out.
“Chances are it’ll probably be a year or two before we actually get a vaccine. The fastest we’ve done is closer to 10 years. The safety thing is the thing that’ll get everybody’s attention, right? You want these to be absolutely sure before you go ahead and give it to a broader population. Manufacturing is a challenge as well, not if it’s an RNA vaccine. If it were the Vector vaccine, which (is) actually a virus that you introduce, that’s the harder one because you go to the traditional vaccine making, but the RNA vaccines are really quick. We’re talking about just making a synthetic protein really quick. So we don’t know which one will be successful. Going by history, so far there has not been a truly successful RNA vaccine, not because they’re bad; it’s just never been tried because it’s a newer technology. Now that we have the ability to make nucleic acid in a simple lab, hopefully the future is bright for that because that would be really quick.”
Q. “What is the difference between an RNA vaccine and a Vector vaccine?”
A. “A Vector vaccine, basically think of it as you take another virus, in this case adenovirus; a common cold virus, and in that virus you put in genetic material that resembles the coronavirus itself. So when the body recognized the cold virus, it extracts that little piece that is strange, or foreign and builds antibodies to that. So in that way you’re safely giving a common cold virus that does not replicate to someone. The most successful case (study for Vector Vaccines is in) Ebola, the Ebola vaccine was basically an adenovirus-based vaccine. But RNA is much simpler, you’re taking the basic genetic building block of a virus; for (Human beings) its DNA, for the coronavirus it’s RNA.”
Kurra explained the outer shell of the coronavirus; with its jutting spikes that give it its distinct crown-like appearance and help protect the virus from antibody attack. The spikes are what allow the virus to latch onto the receptors of a cell. An RNA vaccine introduces a modified version of the virus without that outer shell, which allows the human body access to the basic genetic blue print of the virus.
“You just give it to the human body, and the body processes it and then develops antibodies to that RNA. It’s basically very clever engineering to make our bodies recognize a virus. What you’re basically doing is, you’re feeding the human immune system a blueprint of the viral protein.”
Q. “So for those that do not develop antibodies, are their immune systems just not able to crack that code?”
A. “What we do know from best clinical evidence … these are studies done with a case control so you take groups of people, those that had the virus, and you follow them for at least 28 days and in some cases up to 30 days; 100% of them develop antibodies and T-cell response to the virus. So what we know from these studies, the best evidence is, we all develop antibodies in response to the virus; just the timing of it might be the difference.”
Kurra said there are anecdotal reports of people not developing antibodies, but those reports are unsubstantiated by research.
“All of the studies that have been well-designed show that we do develop antibodies 100% of the time. The question is, ‘how long do they last.’ … There are some folks, within a few months, they don’t have antibodies so if you test them a few months out, you might say, ‘oh, well they never developed antibodies,’ which is not true.“
Q. “What does this virus actually do to the body?”
A. “It’s a respiratory virus, just like the flu in that specific sense and the analogy stops right there, but it affects mainly the lungs. It causes pneumonia, … and what we have come to know is that most deaths occur because of a run-away inflammatory response. The virus itself, strangely, causes the human body to overreact. In the few cases that died and (that overreaction did not occur), it has other things it does. It causes blood clots to develop in blood vessels causing strokes, causing heart attacks, causing injury to the heart muscle. It pretty much affects any place where there are blood vessels, which is basically every organ of the body. This is a novel virus, (new to the global population). If you look at influenza it’s been around over 200 years.”
Kurra said that although the influenza virus has been around for so long, it was a new mutated strain, which struck the U.S. in 1918, which is what made the virus so deadly at that time.
“So when the 1918 flu pandemic occurred and a lot of people died, it was new because for generations no one had seen that specific mutation. The same 1918 flu is still around, (but) none of us have a run-away inflammatory response because generations of us (have developed antibodies to fight it). When it’s novel, the body tends to (overreact), but over time, 10 years from now if this virus doesn’t disappear and continues to stay endemic, then we probably won’t mount an immune response like we’re doing right now.”
Q. “Is that where the term, ‘herd immunity,’ comes in?”
A. “Yeah, that’s exactly right. So if it’s not new, just like influenza we’ve seen it for over 150 years, as long as it’s not a new mutant form of it. … In 1918, even though 100 years prior to that there was an influenza virus, the 1918 mutant strain was unknown. So yeah, we’ll develop herd immunity but not if there’s a complete change in the virus.”
Kurra explained that every 50 years or so, viruses can mutate and change so much that our bodies can’t recognize it as the same virus, so a completely new set of antibodies needs to be developed.
Q. “If herd immunity is the natural course of letting a virus spread through a population to develop antibodies, why are we taking such measures to prevent it from happening such as wearing masks, and social distancing?”
A. “Great question, so here’s what we have to recognize-there’s a cost. And that’s the question that people have a hard time understanding. What’s your risk aversion, what’s the amount of risk we’re all willing to face? My answer is always, if we can stave off any spread at all, until we can get to a vaccine or a treatment … that would be great. … That’s a core part of (being an internist): you want to prevent and then control and then find treatments. That’s what we did with Ebola: they have a vaccine that’s successful right now, and that stopped that spread of Ebola in the continent of Africa.
The cost to developing herd immunity and having this spread unchecked is more devastating to the human body even in those that survive. We have seen devastating effects to their internal organs that, in a way (are) preventable. It’s like drinking dirty water and recovering after having some diarrhea from it, even (the specific strain of E. coli that causes diarrhea) can damage kidneys. So what we want as people who care about the health and well-being of the community is to figure out a way to live with this virus while protecting the most vulnerable, which means slowing down the spread so it doesn’t get to vulnerable people like the older folks, people with COPD, diabetes, hypertension, and cancer. For some reason we want to see everything sped up in time. In the natural world, if you let it go over time a slow spread (is ideal). Think of it almost like a controlled burn: it’s better and it actually has huge impacts as far as the quality (of life for) the people of this country and the world at large. You want a healthy population that learns to develop (antibodies) over time rather than just burning through. Burning through leaves people scarred, if it doesn’t kill people.”
Q. “People are recommended to wear a mask to help prevent the spread of the virus. What about coming into contact with the virus through other means?”
A. “I think this is the part that gets a lot of attention (but) people don’t understand it. (Wearing a mask) does not protect you. What you’re doing is, it takes five days for people to present symptoms; you have five days to spread it around your community. What we’re doing with the mask is basically preventing your droplets from coming into contact with another person, and it’s the most simple and the most efficient, and most effective, profound way of slowing the spread of the disease.”
Kurra said the virus is carried on droplets, which can enter the body through many ports, such as the eyes, mouth, and nose.
“That’s why we say stay six feet (apart). … If you wear your mask, and keep your six-foot distance, when you talk, those droplets have nowhere to go but the back of your mask and they stay there. And you kept your six-foot (distance) so you’re not getting them in anyone’s eyes either.”
Kurra explained that in a hospital setting, doctors and nurses who see patients with known exposure to the virus will wear masks and full face shields to prevent the patients’ droplets from coming into contact with any vulnerable port of entry, but that kind of covering is not necessary for everyday activities.
“As long as you don’t touch your face, wash your hands, (wear a mask), and keep your six-foot distance, you actually are doing a mighty service to human kind because you are slowing down the spread by these very simple acts you have changed the world-we wouldn’t be seeing what we’re seeing today, and it’s hard to convince folks of that. It sounds a little bit not important, but the compounding factors; you’ve seen the numbers, the run-away spread, what we call the exponential curve of infections, is very, very frightening. If you don’t have anyone that you know who has the disease, then your job and mine as well is to wear that mask and keep that distance.”
Q. “Studies are being quoted saying that children are less likely to transmit the virus even though they can still carry the virus. What is the science there, how does that work?”
A. “T studies out of Europe: what they showed was children under the age of 10 don’t transmit it as effectively, they do transmit it; their rate of what we call attack rate, or transmission rate is about 3.5%. Children between (ages)10 and 20, those folks transmit about 15% to 18%, so they are approaching what we would call ‘adult rate of transmission.’”
Kurra said although more research is needed to definitively prove what the reason is for the discrepancy, there is no evidence that suggests children are physiologically less likely to transmit the virus. Instead, Kurra pointed to the behavioral differences between younger and older children.
“Imagine the difference between what a less-than-10-year-old can do and an older kid (can do). The older kid is almost acting, from a sociological and behavioral angle, like an adult, while a less-than-10-yaer-old is not behaving like an adult. … How many kids go out to the grocery stores, or bars, or restaurants, or any of these? … So in a kind of way, it’s our own social and the growth and development reasons that a 10-year or younger (person) is unable to transmit it effectively. It’s not because they don’t; because we know they do. There was a very robust (study) done in Denmark and another one out of France, … it has to be tested, but it make sense that (younger children) don’t act and behave like adults. For schools reopening, that’s the problem. There have been a lot of debates around these things, but what has been clearly evidenced across all countries, all states, across the globe, the foundational aspect of preventing transmission is keep your distance six-feet, don’t gather in crowded places, no close contact, wear the mask, wash your hands, do not cough or sneeze openly, and then of course don’t touch your face. In every single instance, when these are followed, you can almost completely stop transmission of this disease.”
Q. “What should we be thinking about when we talk about opening schools?”
A. “When you look at successful school openings in other countries, there are lessons to be learned. ... Finland, Germany, and Denmark have been great examples of very successful openings, the number one thing is, you want to have very low levels, vanishingly low levels of community-based transmission. All the places I mentioned successfully did that because they had less than three new cases per hundred thousand per day. When you have sustained transmission like right now in the South, and the southern states and Western states that’s a bad time to be opening schools. (Finland, Germany, and Denmark) did it well because they brought their numbers down … Other things that they did very well is they only had 10 kids per room. In fact they even made concessions and opened up museums, libraries and banks to hold classes because the classes were small … not only that, they had to wash their hands, students and teachers, every two hours, they had at least once a day cleaning of all the school areas, they had no gatherings larger than 10 at a time, and so all these are very, very, important measures. (They sound) like impossible to reach standards in order to keep that down, (but) if we want to reduce transmission, we need to do (those) very things they did masking as well. It’s fascinating when you look at all these countries that did well, and then those that did not do well did the opposite or pretty much did not do most of the things (the others) did. A good example is a study published in Israel. They opened high schools, and they had two large outbreaks in the first 10 days of open school. They opened school May 17, they had a heat wave and asked the commissioner, and they said, ‘OK, you have three days; you don’t have to wear your masks,’ and exactly five days after those three days the two index cases, what we call the cases that started the outbreak in the schools, developed COVID-19. So it just goes to show, the basic infection control practices remain the same universally; it doesn’t matter where you are and those are the kind of things you learn from. You want to practice very strict infection prevention practices.”
Q. “With South Dakota’s numbers being where they are now, do you think we can open schools safely?”
A. “That question is a very difficult one, because yes you could, but you have to do all the other things also that go with that. I wish it was a simple, ‘yes, the numbers are low, you open schools and everything will be all right.’ You saw that in Camp Judson, suddenly you have 32 and the next day you had 62 positive cases. The same thing happened in Indiana, two schools … within two days they had an outbreak. And the reality is, numbers are one thing, you still have to do the hard things, which are the infection control practices, and if we do that right, even at a larger scale, we could open schools sooner because we would have low transmission rates. But that’s not what I see if you look up at the map today. It is rampant, it’s spreading, it’s unmitigated spread, and that’s the problem. And if we do this, not just schools, but each of us adults have to take that ownership and do it right for our vulnerable and help our people. I don’t think we are forever destined to live isolated lives; that’s not who we are. Human beings have come through other diseases as well. But what we need to do, the common sense thing and the epidemiological thing is to slow down the transmission by doing safe practices, infection prevention practices.”
Q. “With major events taking place, and schools opening, what should we be doing?”
A. “Don’t lose sight of the simple things that have kept South Dakota and West River really fortunate because I believe the community has come to its own aid by doing the right things. Wear your face mask, wash your hands, don’t touch your face, keep your distance-six-feet in grocery stores and anywhere, do not gather in close spaces. I’m sad to say this because the economy does get hurt when I say this, but that’s our way out of this and get back to a healthy economy is to not gather in close crowds and confined spaces. If that is done even for a month, things will turn around. Even with the Rally coming, each of us in the community, since we live and breathe and work and enjoy life here, that’s what we need to do and when we do that, despite the Rally, we’ll be fine. This is the way you stop something like this from spreading.”
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