Infectious disease expert Dr. Lisa Barrett answers viewer questions about COVID-19: Part 3
HALIFAX -- The information surrounding COVID-19 can be overwhelming and, at times, hard to understand.
Many Maritimers have had questions about the virus itself and how to deal with it. Particularly, when some of the messaging continues to change, as the science community learns more about the disease.
Dr. Lisa Barrett sat down with CTV News Atlantic anchor Steve Murphy on Monday night to provide answers to the ever-changing questions about COVID-19.
Dr. Barrett is a medical doctor and clinician scientist with expertise in infectious disease and human immunology.
In addition to a PhD and MD from Memorial University, an internal medicine residency at Dalhousie University, and an infectious disease fellowship at the University of Toronto, her training includes post-doctoral training at the National Institute of Allergy and Infectious Diseases in Bethesda, Maryland.
During her training at the National Institute of Health in Maryland, Dr. Barrett worked with prominent American physician and immunologist, Dr. Anthony Fauci, who is a member of the coronavirus task force in the United States.
Below is a transcript of the interview:
1. Is the COVID-19 testing able to tell if someone has had the virus and has already recovered? Wondering if the virus was here before we knew, or before the testing was available.
- Nicole McLearn
Dr. Barrett: To answer the question about whether or not somebody has been recovered, the current tests that we do at the moment, that are available and the most reliable ones in Canada right now, are ones that tell you if you are actively infected or not. To a certain extent they detect the actual genetic fingerprint of the virus, and it’s a yes or no.
However, it doesn’t tell you if you’re protected or if you’ve had the virus before, and so those tests are being developed and will hopefully be available soon.
Certainly lots of us wonder if this virus may have been around a couple of months before we realize it, many people come to me and say, "I’m sure I had this in January or February," and we don’t know the answer yet, but it’s certainly something that’s on a lot of our researchers minds, and hopefully something we can look back at afterwards.
2. Why are Canadian health officials not using the COVID-19 test kit that uses a drop of your blood, gives results in 3 minutes, and is about 1/5th of the cost of the test being used now?
- Sandra Boudreau
Dr. Barrett: The test we use right now is a direct test that looks for the genetic fingerprint that tells you if the virus, or its genetic material, is present or not. This particular blood test that she’s mentioning is not yet approved in Canada, and it looks for antibodies, so your body's response to having seen this virus before. While it can tell you if you’ve been exposed to the virus, it can’t tell you if you’re actively infected, and it’s not truly approved yet in Canada.
One new test was approved today or yesterday by Health Canada, but it does not detect the antibodies, it’s not a blood test, it’s still a swab and we do not have access to it here yet.
3. There’s a lot of talk in the U.S. about the use of the malaria drug called hydroxychloroquine as a possible treatment. What are your thoughts?
- Several viewers
Dr. Barrett: So there are two related medications, very similiar in name, so chloroquine, which is the malaria drug, and hydroxychloroquine, which is a newer version of the medication chloroquine, which has fewer side effects and is most often used in rheumatologic conditions.
The two are supposed to potentially have some direct effects on inhibiting the SARS/CoV-2 virus, which causes COVID-19-related disease, however, we’re not certain yet. In addition, it may also down-regulate your immune system, which is what causes that late lung disease that we see that is so damaging in COVID-19-related disease.
So, hydroxychloroquine, we don’t know if it useful in treating or preventing people from getting worse if they are infected with COVID-19, and that’s why we are doing studies, both in Canada and around the world to assess whether or not it’s actually useful.
4. How long after exposure does testing turn positive? There are cases of people who are initially negative and then turned positive.
- Kathy Walker
Dr. Barrett: We don’t exactly know the answer. Does that make everyone mistrust a negative swab? It shouldn’t. Most of the time, when you are infected and you have mild to moderate symptoms, if you do a swab and it is done properly, that test will become positive.
However, sometimes if you’re very, very early in your infection and barely have symptoms, the test may not be able to pick up your infection, or in points where your disease has progressed to very late, it moves down into your lungs, and at that point the swab may miss it.
Do we know exactly how long it takes to go from a negative to a positive? Not exactly. But by symptoms, which is a much more practical way of thinking about it, we know that the vast majority of the time, when you have mild to moderate symptoms, that test will be positive. If it’s negative up front, and you get worse symptoms over time, then you could go from negative to positive in several days.
We don’t have exact numbers yet, we’re still waiting for those to become available as we do this testing in this country.
5. If you have recently recovered from COVID-19 are you immune? Could you still transit it to someone else?
- Margo Spreng
Dr. Barrett: We don’t know for certain how much of an immune response you develop, and how much your body fights this off, how protective that is about every infection yet. We’re not certain, we just don’t know the answer. The suspicion is that there will be some protection, that if you ever run into this virus again you will not get as sick, but whether it will completely prevent you from getting a repeat infection is not clear yet -- that’s work to be done.
The next question, about whether or not people who have recovered could still have the ability to affect other people, and again, not exactly certain yet, but the evolving evidence says that after you’ve recovered and your symptoms are gone, because the time when you’re symptomatic, coughing and sneezing is when you’re most infectious, it’s very unlikely that you’re very contagious, even though some studies report that the genetic footprint may still be detectable in the back of your nose or throat, it’s very unlikely that you are very contagious to another person after you’ve recovered.
6. Why are they saying a mask will only work if the wearer is positive to keep everyone safe? Why does the mask not work in keeping the wearer safe? Basically it should work both ways.
- Sherry and Creig Veinot
Dr. Barrett: When we say "works," what we mean is, what is the most effective thing that a particular mask does. And the mask I’m talking about would either be a procedural mask, so those standard surgical masks -- which, by the way, I am hoping only those involved with the healthcare system, either as a healthcare worker or patient are using at this point -- or a mask that people seem to be fashioning or buying themselves.
The reason we say that it only works to keep droplets in, so not even if you’re just positive, but mostly if you have droplets, that those will be caught definitely by the mask.
The masks that we have, the procedural ones or the handmade ones, likely don’t have the same ability to have that very special fabric that masks like the N95 or others. That special fabric prevents teeny-tiny droplets and viruses from being able to get in. And that’s why droplets are prevented from getting out, but viruses may still get in through a procedural mask or a handmade mask.
That’s not to say there may not still be some benefit from keeping you from touching your nose or your mouth, but for the most part, that very special fabric layer that’s inside special masks is not present to prevent virus particles from getting in.
7. Is there any chance that COVID-19 could be transmitted by insects?
Dr. Barrett: Not to our knowledge at this point.
8. I hear a lot of people say that dogs can get the coronavirus. I have two small dogs and would like to know if this is true?
- Jeanie Walsh
Dr. Barrett: Although this is not SARS, it is a virus related to the SARS virus, and we know that during that period of time, when that coronavirus was around, there were some small animals including cats, and maybe some dogs, that did seem to be able to shed some of the virus. However, they did not seem to get a clinical disease that made them sick, even though they may have had some virus in them.
So, at this point, the general answer is that your animal may get a virus or two from it, but probably isn’t going to get sick from it, as far as we know right now.
9. Is it safe to go outside and clean the yard and plant flowers? Should we wear a mask?
- Wayne LeBlanc
Dr. Barrett: So, if you’re in your backyard or frontyard all by yourself, with no one else around you, and you are an excellent hand washer and non-face toucher, then you should be OK.
We know that this is droplet-born from one person to another, from droplets made when a person is coughing or sneezing, and if there is no one around you, and the last time you were around someone or a surface that may have been contaminated you washed your hands, and you don’t touch your face, then there is no way for those respiratory droplets to be around you, or to get in from your hands, and therefore you should be pretty safe if you’re on your own.
10. Will it be OK to open up swimming pools and use them this summer?
Dr. Barrett: Swimming pools have different types of water, chlorine or salt water, or the like. The point is that’s still not the way we transmit this virus, which is person-to-person through respiratory droplets.
Whether or not there’s a little bit of virus that can get into a pool is likely to be pretty irrelevant at this point. So, I’m guessing that it’s going to be OK to open your pool this summer, but honestly that’s not a question I have come around to thinking about, considering the 4° weather right now.
11. After shopping for groceries do we need to clean everything before putting them away, and is soap and water enough?
- Marilyn Woodworth
Dr. Barrett: This comes back to how you spread the virus, which is through respiratory droplets from person to person, or if somebody had sneezed or coughed on one of your groceries. That may or may not survive for very long -- the estimates are between three hours and 72 hours that a virus could be present and be able to move on to another person.
Do I wash my groceries? I don’t. I do make sure I am impeccable about my hand-washing and not touching my face. If people feel the need to give something a wipe down with some soap and water, this virus is surrounded by a fatty layer that will be disrupted by regular old soap, and therefore it should inactivate the virus on the surface.
But, quite honestly, the key, key part of anything in this world, is stay away from others, wash your hands and don’t touch your face.
12: Does putting things in the freezer kill the virus?
- Stephen Cassidy
Dr. Barrett: We’re not actually certain. Some coronaviruses can live for a long time, but then that comes back to the question of, does coronavirus on a piece of food actually cause infection? And we don’t have any evidence that has happened yet, from cooked food or otherwise, so I would suspect that either way, it is very low risk.
This is the third interview in a series of COVID-19 Q&A's with Dr. Lisa Barrett: