COVID-19 Update 7/8: Airborne Transmission, Immunity, Antibody Treatments, and Football
Another week, another COVID-19 update from Dr. Steven Bishop. This update is jam-packed of information based on questions from viewers. Watch the full video and read on for a recap on airborne transmission, the risk of infection at colleges and schools, immunity and antibody treatments, the likelihood of football, and much more.
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Airborne Transmission of COVID-19
This is something that we've been talking about for the last several months. There does appear to be some component of airborne transmission with COVID-19, as opposed to droplet transmission. Droplet transmission would be when someone coughs and within 6 feet or so, there can be spread of the viral droplets before they fall to the ground.
There is some data that air samples are containing some viral particles beyond 6 feet. There have been case reports where some people may have gotten the virus either through a ventilation system or being in poorly ventilated areas, etc. There does seem to be some airborne component, as opposed to just the droplet transmission within a few feet of someone. It's probably less of a threat than droplet transmission and contact, but it does seem to be an issue.
The biggest thing with this is, when you go out to places, make sure they have good ventilation systems. I know a lot of doctor's offices and dentist's offices are using special UV-light cleaners in their ventilation systems and things like that. Being outdoors seems to cary some lesser risk of transmission, so a lot of the outdoors activities people are doing are fine.
Being indoors and in crowds is definitely a higher-risk situation based on this information. But a lot of places have good ventilation systems, so the risk in those places would still be fairly minimal.
Risk of Infection in College Dorms and Schools
As kids go back to school, for those that will be doing classes in person, there will be increased risk of transmission. Whether they consistently wear mask and wash hands or not, there is going to be some risk of transmission when getting large groups together.
The overall thing with this virus relates to the mortality of the group that is school-aged, or basically 40 and under. The under-40 group's mortality rate is very, very low and is comparable to the seasonal flu. My personal opinion and my medical opinion is it doesn't make a whole lot of sense to prevent people from going to school or college for a virus that is no more dangerous to them than the usual flu would be. I think it is reasonable to resume those activities as much as they possibly can.
Now, of course, that doesn't address the risk to staff, teachers, etc. But managed well, if people wear masks, if enhanced cleaning occurs, I think the risk can be minimized and the risk to students themselves is pretty minuscule compared to people older than 40. They will spread the virus around, but the risk to young people in general to have bad outcomes is not high.
How to Balance Ongoing Treatment Needs vs. COVID Risk
This question related to cancer treatments and how patients should cope with managing ongoing care being rescheduled versus the risk of contracting the virus. Many are facing this issue, and not just cancer patients, but pretty much anyone with a condition that requires ongoing care.
There are no easy answers. I would recommend talking to your oncologist to try and figure out how to minimize the number of times you have to go out to get medical care. Anything you can do via telemedicine should be done, and you should make sure whatever facility you are going to, whether to get transfusions or something else, is following the utmost in cleaning protocols and being as safe as they possibly can.
In general, I would continue to minimize outings in public and ask your doctor to check into the healthcare facility to see what they are doing to clean before you go. After all, doctors are supposed to be advocates for their patients and a simple call to ask questions about what they are doing to clean can speak volumes and lead to positive change if there are problems.
What's the most important metric to follow for coverage of the virus?
In my opinion, it's hospitalizations and deaths. To me, those have always been the metrics. Back in early March, the whole idea was to "flatten the curve." It wasn't to stop spread of the virus; it was to spread out the spread so the hospital systems would not get overwhelmed.
To me, the most important metrics are how full are hospitals and how many hospitals beds are there available, both ICU beds and regular beds. The part where this gets tricky is that you'll constantly hear about hospitals being 90% full or something. If you dig into the weeds of that, most of those patients are not COVID patients. The reality is that most hospitals are almost full all the time and have been for many years. We are short on ICU and hospital beds almost all the time, especially during flu season all the time.
So for me, if hospitals are sitting at 98% or 99% capacity, especially the ICUs, for many days and they are having to turn sick people away, then that's the time where we would need to do something different and reintroduce restrictions so we can slow down the spread and reduce hospitalizations.
Have the protests made the spread of the virus worse?
The short answer to this is that we have no idea. There's been a lot of competing articles coming out that saying one thing or the other, but in reality, no one has any idea. It takes time for the data to come out. A lot of how they figure out how virus is spread is through contact tracing. And I don't think we'll ever know one way or the other if the protests actually worsened things or not.
What we do know is that the protest started the end of May and the number of cases has gone up through June. And that also coincides with places reopening aggressively. So it is difficult to know the impact of the protests vs. reopening vs. both together. That being said, even though the cases has skyrocketed through June, the number of deaths is basically at a low from when these things began.
It does make me suspicious that the spread in these new cases is mostly among the young and the healthy, which would be people who are protesting or who could be out and about in general.
Any updates on immunity?
Yes, some maybe not good news. There's some data coming out showing that the antibodies may not last very long. This may or may not mean anything. Just because antibodies aren't detectable doesn't mean you don't have some immunity. Antibody levels can be low. They may just be too low to be detected by the current tests.
But we all carry something call memory cells in the immune system. There are both Memory B cells and Memory T cells. Memory B cells are the ones that remember how to make the antibodies for certain illnesses. They can stick around for a lifetime. Even though your antibody levels may go very low, those Memory B cells might still be hanging around. They are tougher to find and are not something you can figure out in a simple blood test.
Same thing with Memory T cells. Memory T cells are basically hunter-killer cells that go around and destroy infected cells. You can't really test for those either. So while people may have had antibodies that are now gone, people may have Memory B or Memory T cells that are hanging around and still have some immunity to the virus even though the antibodies are no longer detectable.
There is still no guarantee that the immunity we get from these antibodies is going to last. It's going to take a long time to figure that out.
More Questions. More Answers.
- Can you catch the virus by just walking by someone?
No, walking past someone is not a high risk activity. The risk for airborne transmission comes in an enclosed space with others, even if you are more than six feet away from them, there is still the possibility of transmission.
- Is information from Dr. Fauci more reliable than that from the pandemic task-force? I think he is more practical about what’s going on, but the task force seems to be treading carefully so as not to step on political toes. (I hope this is a question you can comfortably answer. )
By and large, most people involved — Dr. Fauci, the task-force, etc., — are trying to balance competing needs and interests. Dr. Fauci, and any physician advising political leaders, is in a difficult position because they are trying to advise an elected official on the pros and cons of various courses of action. That's the task-force's job, too. Then, ultimately the elected official is the one who has to make the decision about what to do.
A lot of other people — the media, state politicians, senators, etc. — pressure Dr. Fauci and the task-force to tell them "we should X" or "we should do Y." I don't think its fair to ask Dr. Fauci or the task-force to make proclamations about what we should and shouldn't do. Their job is to give advice on the pros and cons of "if we do X, this is likely what will happen" and then the president or governor, or whoever it is, takes that information and balances with competing needs from legal needs, economic needs, and all the societal inputs.
Overall, I think the information from Dr. Fauci, the taskforce, and the CDC is roughly reliable. The WHO has not been reliable throughout this pandemic.
- It’s great that deaths are way down! But what about Dr. Fauci’s comment that “touting the mortality rate is a false narrative”?
To a certain degree, I agree with that statement. That's why, when you're tracking this, it's important to track hospitalizations in addition to deaths. The death rate is something that is good to know about and that we need to keep an eye on, especially as it makes its way around the younger population.
I think what Dr. Fauci is talking about with the mortality rate piece is — yes, say right now most of the spread going around is with young, healthy people, so they are not dying, and that's a good thing. But if we get too casual about the whole thing, then people will stop social distancing from our grandparents, our elderly neighbors, etc., so the pandemic could go back into the more at-risk populations where the mortality rate is horrifyingly high — 30% in the 80+ group.
That's the message he's trying to send. Don't be flippant about the death rate being low, because the virus could spread back into vulnerable communities. We need to continue to aggressively protect those populations, even as we try to get back to some sense of normalcy in the broader world.
- I don't understand, from a medical standpoint, why antibody therapies are only a bridge to immunity, rather than a cure. Wouldn't somebody who receives antibody treatment still be independently building their own antibodies to the virus, as well as T- cell immunity? Why wouldn't those immunities carry forward?
There are two ideas. If you are using antibodies as a prophylactic treatment, that's a bridge to a vaccine. One of the companies is developing the "COVID shield," which is a cocktail of three antibodies as an injection you give someone every week or two to prevent the illness. That's not going to stimulate them to produce their own independent antibodies, so as soon as those antibodies degrade and leave the system, there is no long-term immunity conferred.
If you are using antibodies in someone who is sick with the virus, and they have it, then yeah, that would be an adjunctive treatment and they should be developing their own B and C cell immunity while the passively given antibodies do their work to give the body time to create a better immune response.
- What do you think about the news reports of possible widespread T-cell immunity?
It's very interesting. I hope it's accurate. It makes a lot of sense. There are two main ways the body controls viral infection. One is to prevent infection to start with and the other is, once infection has set in, to go in and destroy infected cells so they can't be used to replicate the virus. B cells and antibodies try to prevent infection and then the T cells are the assassin cells that go in and destroy the cells that do get infected.
It is certainly probable that people have Memory T cells for coronavirus, just like they do for many other viral infections. That's a little bit of what we talking about earlier with Memory B cells and Memory T cells and how that's not something that is easily measured with a simple blood test.
- When the first vaccine is released, do you run immediately out to get it? Do you wait for others to come out to see which is more effective?
I would say we're going to have to see what the data shows. Before I get anything or recommend anything, I'm going to want to see the safety data, see how well it works, if it prevents deaths, hospital stays, severe disease, etc. And then we'll have to test the risks and the benefits.
And it will depend on if the first vaccine that goes on the market is a new technology that has never been used before. Such as the one from Moderna that is an MRNA vaccine, which has never been used to create a vaccine before. So I will be scrutinizing the data on that one a little more seriously versus a vaccine made on technology that we've been using for decades.
Because of what will probably be limited supplies at first, I doubt anyone will be able to run out and get it immediately. It will probably be released in phases. I saw a report this week that there are committees being convened to lay out the sequence of people getting the vaccine.
My suspicion is it will be available to healthcare workers first and then high-risk people (60+ age range and chronic diseases), and then they'll work their way down to the rest of the population.
- Last I heard the antibody treatments were still anticipated to be available, potentially, in the fall. Is that still the expectation?
I think so. That being said, some of the early studies I've seen have not shown positive results from using the convalescent antibodies. Now, I have not seen anymore trials from the COVID shield, so I don't know. But possibly. I think we will see something come out in the fall, because it's simple and old technology and people will probably get through the safety trials quickly because of that.
But that last I saw the data on giving people antibodies from people who had recovered, the results were pretty mixed. These commercially produced products might be a little different, because they have neutralizing antibodies. A person who has recovered might have a mixed bag of antibodies that combined aren't potent enough, while a commercial product will have all neutralizing antibodies that could be more effective.
- Will there still be football?
That's an interesting one. It might have to be like the NBA, where they have to find some place to quarantine everybody.