>> Hello and welcome, everyone, here on Zoom and on Facebook. Thank you for joining us for today's virtual event. I'm Liz McClune lead of CDC's Project Firstline and infection control training collaborative, and I'm joined here by three wonderful infection control experts here from CDC, Doctors Alex Kallen, David Kuhar, and Abby Carlson. Dr. Kallen is chief of CDC's Prevention and Response branch here in the Division of Healthcare Quality Promotion, and Dr. Kuhar is lead of CDC's Hospital Infection Prevention Team. Dr. Carlson is an infectious diseases physician with CDC's Project Firstline. She and I recently chatted just a couple of days ago about what the Delta variant of SARS-CoV-2 means for infection control and healthcare. We're going to show a recording of that conversation now, and then we will open it up for a live question-and-answer portion for today's event. While you're listening, feel free to either put questions in the comments part of Facebook or the Q&A part of Zoom, and we will do our best to answer as many as we can. And for now, let's take a look at that great conversation we had with Dr. Abby. Hello and thank you for being with us today. I'm here with CDC's infection control expert, Dr. Abby Carlson, for a discussion about the Delta variant of SARS-CoV-2, the virus that causes COVID-19 and the infection control tools and actions that can protect you, your patients, and your colleagues while working in a healthcare setting. Dr. Carlson is a physician with CDC's infection control training collaborative Project Firstline. She trained in infectious diseases and before joining CDC spent the first part of the pandemic as a practicing infectious disease doctor and healthcare epidemiologist, specializing in infection control. Glad to have you, Dr. Carlson.

>> Happy to be here, and thanks for the introduction.

>> For those of you that aren't familiar with our program Project Firstline, it helps frontline healthcare workers to understand and confidently apply the infection control principles and actions necessary to protect themselves, their facility, their families, and their community. The COVID-19 pandemic has reinforced the importance of healthcare infection control and keeping us all safe and healthy. Since we launched in October 2020, Project Firstline has released a variety of infection control resources specific to COVID-19 and healthcare, including a video series, a facilitator toolkit with guided session plans for infection control trainings, as well as short videos and job aids. Find us at cdc.gov/ProjectFirstline. Today we are here specifically to hear from Dr. Carlson about SARS-CoV-2 variance, including Delta, and the updated recommended infection control actions that will help protect you and your patients. Many of you have heard that the Delta variant is more contagious and that fully vaccinated people who become infected with the Delta variant can spread the virus to others, but how else is Delta different if at all from previous variants and the original version of the virus? And what are the updated recommended infection control actions for healthcare workers during COVID-19, and do they protect against the Delta variant? Dr. Carlson, I'll turn it over to you to start our discussion.

>> Thank you. Thank you for inviting me today. I'm happy to be here, happy to help answer your questions. Today we are going to be discussing the Delta variant of SARS-CoV-2 and what that means for infection control in healthcare, and as we start our discussion, I think it's important to remind everyone that variants are not new. Variants happen all the time with viruses, with all viruses, and new variants emerge regularly. It's why we commonly hear about different strains of the flu and why you can get a cold more than once.

>> So if viruses make new variants all the time, what makes some variants survive and become dominant like Delta while others don't? Do they spread differently?

>> So every time a virus enters a person's body and invades their cells, it makes copies of itself, and that includes the instructions that it needs to make more copies in the future. Sometimes, during the process of copying, mistakes are made, and when the instructions are copied wrong, the virus builds in a slightly new way with those mistakes included, creating a new variant. Some variants cannot survive, but sometimes a variant develops that makes the virus better at infecting people, which is what we're seeing with Delta. Even though a variant like Delta might spread more easily between people than other variants, it actually uses the same path to spread as previous versions of the virus. Delta still primarily spreads from person to person through respiratory droplets, and the way those droplets spread is the key to our infection control recommendations.

>> That's very helpful background. It's good to know that even though it is more contagious, the Delta variant still spreads the same way as previous versions of the virus, through respiratory droplets. Before we talk about what that means for infection control, do we know why Delta spreads more easily between people?

>> The available data show that Delta is more than twice as contagious as past variants. What does that mean? It means that on average, a person infected with the Delta variant will spread SARS-CoV-2, the virus that causes COVID-19, to over twice as many people than if they were infected with the original strains of the virus. How does that happen? So there a number of possible reasons. A more transmissible virus strain might survive better giving it a higher chance to get to a place in the body where it can cause infection. It also could be better at getting into and sticking to cells, and this is important because getting into cells is how the virus makes copies of itself and also how it makes people sick.

>> So we've heard that people with the Delta variant have higher amounts of virus in their noses and their throats. Does that contribute to spread, and does the amount of virus differ between people who have and haven't been vaccinated?

>> Yeah, so some studies have found that people infected with the Delta variant have more virus in their noses and throats than people who are infected or have been infected with previous variants or the original version of the virus, and it might cause more severe illness than previous versions of the virus in people who are not vaccinated. For the people who are fully vaccinated but become infected with the Delta variant through breakthrough infections, they still can spread the virus to others, and they may breathe out as much virus as an unvaccinated person. However, people who have been fully vaccinated are less likely to get infected in the first place, and if they are infected, they will likely spread the virus for less time than people who have not been fully vaccinated. Also, we do have recent data that show our approved and authorized COVID-19 vaccines continue to offer strong protection against hospitalization and death related to COVID-19 even with the rise of the Delta variant.

>> Thanks, Dr. Carlson, for reviewing that important information. We've covered how Delta spreads and what makes Delta different from previous variants of COVID-19. Now, can you tell us what the Delta variant means for infection control recommendations in healthcare settings during the pandemic?

>> Sure, so you may have heard that CDC recently updated its Infection Prevention and Control recommendations for healthcare workers during the COVID-19 pandemic. In general, these updates do not reflect substantial changes to recommended practices. They help further clarify, consolidate, and simplify existing healthcare guidance for COVID-19. That's because even with these emerging variants, including Delta, the basic structure of the SARS-CoV-2 virus has not changed, and that basic structure is what is important for infection control. So the virus still has a fatty envelope that surrounds it, and it still primarily spreads via respiratory droplets, and this means that the infection control tools and actions for those viruses still work. The recommended personal protection equipment or PPE hasn't changed. It still helps prevent the spread of the virus. Proper masking, which as we know, includes wearing a mask over your nose and mouth, keeps respiratory droplets out of the air. Keeping physical distance helps people avoid breathing in each other's respiratory droplets. Having good indoor ventilation is important for clearing the air that might have respiratory droplets in it. Washing your hands with soap and water, it removes the virus from your skin. Using an alcohol-based hand sanitizer still works to break down the fatty envelope which destroys the virus. And then disinfecting products on EPA's List N are still known to kill SARS-CoV-2 including the Delta variant.

>> The updated Infection Prevention and Control recommendations for healthcare settings include the use of source control or actions we can take to stop the spread of germs at their source. Why is source control so important at reducing the spread of the Delta variant?

>> For SARS-CoV-2, SARS control focuses on covering your nose and your mouth to keep your respiratory droplets out of the air. And as I mentioned, the Delta variant still primarily spreads by respiratory droplets. Those range in size from very large to very small, and they are pushed out of the mouth and nose of an infected person when they cough, sneeze, talk, or breathe. Masks that fit snugly around our cheeks and our chin still work effectively to keep the virus from spreading by keeping those respiratory droplets from getting into the air, and that's why our guidance continues to recommend that, in general, all healthcare workers wear their masks or other source control when they're in the healthcare facility.

>> And you mentioned PPE. Can you discuss the recommended PPE and the role it plays for infection control?

>> When PPE is used correctly, it can help stop germs from spreading between you and other people in your facility, including patients, visitors, and of course your coworkers. The recommended PPE when caring for patients with suspected or confirmed COVID-19 are still effective for the Delta variant. This includes N95 respirators; eye protection, so face shields or goggles; and gowns and gloves. And that's because N95's an eye protection, still block SARS-CoV-2 as they always have, and gowns and gloves still help remove any virus you may have picked up from the patient or from the environment.

>> Thank you, Dr. Carlson, for providing this important background information on virus variants and what we need to know about the Delta variant and infection control actions recommended for healthcare workers. Those are all the questions I have today.

>> Of course, glad to be here for this important discussion. I'd also like to take a moment to thank all of the healthcare workers for their dedication and their resiliency during the ongoing pandemic. Each and every one of you is playing a crucial role in saving lives and fighting COVID-19, and we recognize that no one has faced the realities of the pandemic in the same was as those of you in the frontlines, so thank you for staying vigilant. And if we leave you -- if one other takeaway today, we want you to remember that together we do in fact have the power to stop infections. We know that infection control actions for COVID-19 work, and so keep doing what you're doing.

>> Absolutely, and thanks again for joining, and remember to connect with Project Firstline for the latest healthcare infection control training and educational resources. You can find us on the CDC website, in social media, by searching CDC Project Firstline. Thanks, again. I want to thank Dr. Carlson again for taking the time to walk us all through that and about what Delta and infection control, how they relate to one another, and how the actions still work. Now I'm going to make sure we get right started with the Q&A event. First, we'll cover a selection of questions we got during the registration process, and then we'll finish by taking as many live questions as we can. So I'm happy to go ahead and start with the first question. So the first question we have: Are N95s needed for nebulizer treatments? What about for crying babies?

>> I'll take this first question. I'm David Kuhar. Ultimately, so N95s, you know, crying babies, etc. A crying baby or, let's say, a yelling adult, assuming that you don't suspect that they have any disease that requires an N95, an N95 isn't necessarily recommended specifically for that situation. So you wouldn't preferentially choose an N95. You would just choose whatever your selected source control device is. As for nebulizer treatments, which I think is sort of more important to discuss, this gets into aerosol-generating procedures, and whether a nebulizer treatment is in fact considered an aerosol-generating procedure. So on our website, we actually have a list of what procedures we consider aerosol-generating, and I'm actually going to say that the terminology even used [inaudible] what is commonly considered. Believe it or not, for almost all aerosol-generating procedures, the science overall is fairly undeveloped, and I think that this is really important to know. There just isn't a lot of work that has been done to characterize [inaudible] aerosol-generating or not. So the feeling was that the list that we put out that includes things like cardiopulmonary resuscitation, which is commonly considered one of these, are procedures that we erred on the side of -- I would say -- being conservative in deciding what those are. There were some that some studies have indicated there may be increased risk of transmission through -- that includes nebulizer treatments, but this has not always been consistent. A nebulizer treatment by itself generates aerosols of medication so that it can be inhaled by a patient, but it is not creating an aerosol of patient-derived materials, and hence logically it doesn't make complete sense that this would necessarily do that. So I would say, at the moment, the science is not there to really definitively say, yes, a nebulizer treatment is an aerosol-generating procedure or that it's not. And so I would say we wait for more information. I know that there are those who are out there working on it currently. At the moment, we do not consider this a procedure for which you need to take aerosol-generating procedure precautions when doing a nebulizer treatment. Of course, that doesn't mean that people can't do this if they have the means and wish to do so. Anyway, thank you.

>> Thanks, David, and agree. It's good to know where we are with the science and how those decisions were made. For our next question, if you're caring for a patient from a county with high or substantial transmission, but your facility is located in moderate to low transmission -- for example, if the patient was traveling and got hurt and ended up in your facility -- what level of PPE and source control do you recommend, Alex?

>> Thanks. Hi, I'm Alex Kallen. Yeah, this is a tricky question. I think, in general, though, the way that the guidance is framed is try and make it simple and easy to implement, and that's why we base it on the county where the facility sits. So I think in general, you know, we would recommend that that person -- if you're in a low to moderate community transmission area that use low to moderate transmission PPE. Now, again, if you are faced with a person, though, who you do feel is at a higher risk for being infected, generally, asymptomatically infected with SARS-CoV-2 transmission, you certainly could up your PPE. Generally, what that means, right, would be moving from using a face mask, which everybody -- you heard Dr. Carlson say -- should be using in a healthcare setting right now, to adding eye protection, and there's very little downside to doing that. I think the challenge basically is identifying those people to be able to implement that type of a recommendation. So, in general, we'd use the county where the facility sits as a general guide to guide your infection control precautions.

>> Got it, thank you. And the next one is for David. We're going to toggle back to you. When should the N95 that you're using be discarded when used for contact with the SARS-CoV-2 patient, for example, if you're in a COVID unit?

>> Got it. So, in general, your respirator should be discarded after each patient interaction, when you leave a room, for example, along with all of your other disposable personal protective equipment, and this would be pretty standard. I'm going to add a however in here. There is a lot of donning and doffing that happens, especially in SARS-CoV-2 patients that has been recognized as incredibly burdensome, and so our personal protective equipment optimization strategies that have initially been aimed solely at shortages also acknowledge when there is high burden of doffing and make an allowance as a contingency strategy. We don't consider this a standard practice, and we don't consider this necessarily as safe as doffing every time, but to allow people to do extended wear of their respirator, it actually also includes eye protection when they are working in an area with large numbers of SARS-CoV-2 patients such as in one of those units itself. And the idea is you would wear it until you have to take it off for the first time, and then you would discard it and get yourself a fresh one, so potentially going between several patients before actually doffing it. However, again, this is considered a contingency capacity strategy. It is not necessarily as safe. It's really, I would say, just unclear whether it could be just as safe or not necessarily as safe. I suppose it could even be safer. There's just not data to inform this, and so you have that option for extended wear in a SARS-CoV-2 unit if you feel it's something that's really needed. That's it. Thanks, Liz.

>> Got it. Well, and stay off mute because I got a follow-up question for you. Would you recommend wearing an isolation mask with a PAPR? Why or why not?

>> Ah, yes. So, in general, there's not a lot of data around PAPRs and using them for source control. So a PAPR, often a giant hood that you wear that, you know, attached to a belt pack or somewhere else that blows air through that filters the air that you breathe and your -- is blown kind of over your face. It all depends really on where the exhalation valve may be with a PAPR. So many of these are large hoods that cover down to your chest, and the air can just blow downward. And I would say in that circumstance, what it seemed like you needed to wear a face mask under to contain your secretions so you're not exposing other people around you -- And I would say it doesn't seem like that would necessarily be necessary. However, there are also PAPRs that are designed with an exhalation valve sometimes right where your mouth is where you could literally just be blowing out, and the air could be blowing straight onto something else, and those are situations where you probably would want to wear a face mask. In general, because there's a lot of different design variability in PAPRs, if you really want to err on the safe side to make sure that you're, you know, you're doing everything you can for source control, you can always wear a face mask underneath it. But like I said, the need really could be model dependent, and it's just not clear. There's not a clear set way to manage this.

>> Thank you. The next one is for Dr. Kallen. Alex, is eye protection still recommended and why?

>> Yeah, the dreaded eye protection. So CDC still recommends eye protection in two situations -- one, where you're caring for a patient who is known to be infected with SARS-CoV-2, or, you're, you know, suspected to be, so that's part of the full PPE, N95 mask, gown, and gloves. We also recommend eye protection in what we call the universal PPE situation which was similar to the first question I had where you're in an area with substantial to high transmission in addition to source control or a mask, we recommend eye protection. That still is in place. We don't anticipate that changing anytime soon, and basically the bottom line is it's there because to protect your eyes from potential droplet spread of SARS-CoV-2 infection. There are some data that suggest that people with eye protection do have a lower risk of transmission, and so [inaudible] we recommend that. We continue to recommend that for healthcare personnel.

>> Great, thanks, and the next question is also for you. Do nonclinical, meaning those that are in a healthcare facility that are providing direct patient care, need to wear the employer-provided face masks, or could they use a cloth one, or ones that, you know, follow different standards?

>> Yeah, so, again, would recommend that you, you know, follow what your facility is currently recommended. Per our current recommendations, you could use any of those for source control in a healthcare setting. I think we generally try and shy away from the cloth-face mask for people in a patient-facing situation just because you might need PPE and have to change between the cloth-based mask and a medical face mask is just extra challenging, requires you to touch your face, etc. So for patient-facing people, we generally prefer that you use a medical face mask. The other folks could use a cloth-based mask.

>> Got it, thank you. And next one is for David. Because there's an increase in testing just in general in the community, are healthcare workers and -- no longer advised to quarantine while awaiting their test results? What would you recommend?

>> Ah, so we actually do address this in our guidance document, the Interim Guidance for Managing Healthcare Personnel with SARS-CoV-2 Infection or Exposure to SARS-CoV-2, and the bottom line is it really comes down to a healthcare worker's vaccination status. So after an exposure, a fully vaccinated healthcare provider, there is a testing recommended afterwards, but not necessarily quarantine with some exceptions that are actually laid out in there. For unvaccinated healthcare personnel what we consider quarantine in healthcare which is actually restriction from work is recommended along with testing as well. And in general, we have people with unvaccinated healthcare providers who have a higher risk exposure are excluded from work for 14 days after that last exposure as well as tested on a schedule in between.

>> Got it, thank you. This one is also for you. Should an interpreter helping with a known or suspected COVID-19 patient so in the same room also wear an N95 during a dental procedure or any other aerosol-generating procedure, or could they be wearing a face shield or a face mask?

>> Yeah, that's a great question. So, in general, for aerosol-generating procedures, we consider these to be higher risk than normal, meaning that we are artificially doing a procedure that is artificially creating small particles that could be laden with lots of virus potentially and that this could pose more risk than a normal situation. So when that's the case, we almost want all people who aren't absolutely necessary out of the room entirely. We don't want them present at all. So I would say for an interpreter, if there was any way they could not be present for it, that sounds great. However, an interpreter is often someone you would see as essential. Communication with your patient is key, and if the feeling is, you know, look, that we need to have them there, that's fine. You do what you have to do. If they are to be present, they should absolutely be offered the same standard personal protective equipment that you would use for anyone else. It would include a respirator, eye protection, as well as a gown, and gloves while they were there for the procedure.

>> Got it. I just wanted to clarify quickly because of the question asks face masks or face shield as if those were interchangeable, but is the face shield and face mask interchangeable, or is -- are they not?

>> Good question. They are not interchangeable. A face mask is obviously covers the mouth and nose. For SARS-CoV-2, we really want people to wear respirators as their protection so it actually filters what they inhale as opposed to a face mask which just doesn't do as good a job at this. A face shield is actually eye protection, and it one version of eye protection like goggles, etc. But a face shield that extends down below your chin, you know, it's still going to hit what people exhale, but this has actually been tested in a lab. Face shields do not provide source control even close to what a face mask can do. They let tons of stuff fly around them. They are just not a substitute for a face mask for source control.

>> Got it. Thank you for that. And the next one is for you, Dr. Kallen. What data, if any, is there to support this continued focus on environmental cleaning and cleaning of surfaces?

>> Yeah, I think most of those recommendations are based on data that show that SARS-CoV-2 can contaminate surfaces and be picked up after even, you know, extended periods of time. You know, it's hard to show that that then goes on to subsequent transmission, but I think the first part is enough for us to consider it important protect yourself against that. I think, certainly, there's been an overemphasis on the contact with surfaces as a mode of transmission for SARS-CoV-2 [inaudible]. It's really short-range aerosols and droplets probably -- not probably -- definitely more than surfaces, but, still, there are other respiratory viruses that are spread this way, things like RSV, etc., for which we recommend the use of contact precautions, and so for that reason, we still recommend a gown, and gloves, and environmental cleaning for SARS-CoV-2.

>> Got it. So to think broadly beyond just the pathogen-specific things, but more into context of other things [inaudible].

>> Right.

>> And then a follow-up to that then, what is kind of best practice, the best way to decontaminate a room at a primary care outpatient setting when you've cared for a person that is suspected or confirmed COVID-19? Sorry, Alex, you're on mute real quick.

>> Sorry about that. Yeah, not huge differences to how you would do that from how you would normally cleaning, probably with just two exceptions. One, you want to use a product that is active against SARS-CoV-2. There's a list that you can look for products on called List N from EPA that gives you a list of products that have been approved against that particular virus. And the second thing is you want to take into account the potential residual virus in the air. So again, if a patient's in a room, they've been in there for a while, and you're going to go right in and clean it right afterwards, you want to make sure that that person's protected with the PPE that David had said that you would use if you were caring for a person with SARS-CoV-2. So those are probably the two big things. If you'd like, there's some information that you can look at based on how many air exchanges, etc., how long you would have to wait, and you could take a look at our guidance for that, but if you weren't going to use full PPE, but generally that's, you know, a fairly extensive amount of time, sometimes 20, 30, or 40 minutes. So just keep in mind the need to protect the cleaner coming in after the patient to clean the room.

>> Great. Thank you for that. The next one is for you, David. The return to work guidance seems to say that unvaccinated healthcare personnel exposed to someone other than a patient, or a visitor, another healthcare personnel, they don't have to be excluded for work. So can you help clarify? Does it matter when or where the exposure happens?

>> Yeah, this is a really important point and important to clarify. So that guidance without a doubt focuses on how to manage exposures in healthcare, but the bottom line is an exposure in healthcare, an exposure somewhere in the community, an exposure which we define as, you know, a close contact that is considered prolonged within 6 feet for greater than a cumulative 15 minutes over 24 hours that any exposure no matter where it happens is an exposure, period. So if you have a healthcare provider that has an exposure in the community, and they're calling their occupational health clinic wanting to know what to do, you would treat them the same as if they had an exposure that happened in healthcare. If they're unvaccinated, they should be restricted from work, tested as recommended, etc.

>> Got it. Thank you for that. The next question is for you, Dr. Kallen. If your community has low transmission but your facility is having an outbreak, should you still continue masking residents and staff?

>> Yeah, so, again, not 100% sure if this is talking about the old guidance or the updated guidance, but so, in general, everybody should be using -- in a healthcare setting should be using a face mask for source control, patients, residents, visitors across the board. If you've looked at the updated guidance, there's a few exceptions to that which include residents in areas with low to moderate transmission or healthcare personnel in non patient-facing areas in areas of low to moderate transmission, which again is not [inaudible] United States if any right now. So in those situations, if you're in an outbreak, that is one of those things that trumps that recommendation, and we would still recommend using source control in that setting for everybody regardless if you meet one of the exceptions that I just mentioned.

>> Got it and a secondary question related to nursing homes as well. If a resident has contact with a staff member that ultimately tests positive for SARS-CoV-2, but that staff member was in an N95 during their interactions, does the resident need to quarantine for any amount of time?

>> Yeah, so good question. So the bottom line is if both parties are wearing something over their nose and mouth, the resident as well as the staff member, then that's probably a fairly low risk exposure, and in general -- there's exceptions that you can certainly use your judgment for -- but, in general, that's probably not a close contact [inaudible]. So an unvaccinated person wouldn't have to go into quarantine. Obviously, a vaccinated resident doesn't have to go into quarantine even if they're a close contact based on our updated guidance. However, if only one party is wearing it, although, you know, even if it's N95, that still is probably a close contact, and so an unvaccinated resident would still be placed in quarantine.

>> Got it. And the next one is for you, David. I [inaudible] last two are for you, and then we'll go to our live QAs. Is there an amount of time for when you're looking at community transmission levels and trying to identify if you can go down to that moderate or low different PPE recommendations? Is there an amount of time you should wait to see that your community stays in that level? If you could provide some clarity, that'd be great.

>> No, we don't actually, you know, we don't recommend a certain amount of time or a waiting period per say before kind of you could necessarily switch. I would say, you know, if your community seems to be hovering at that -- for a little while -- And I would say most of the country has -- had, you know, been at higher levels. These have been falling. If you're hovering at that, you know, point, maybe keep the precautions for a little while longer until it seems that you're settled below it for a little while. How long would that be? It's really difficult to say. I'd say that's probably community dependent. The bottom line though is we don't have a set amount of time before you would necessarily decide when to step it down.

>> Got it. And the last one is for you too, and it's negative pressure room. Is it required for taking care of a patient with suspected or confirmed SARS-CoV-2 in an outpatient setting?

>> Yeah, a good question. No, negative pressure is not something that is required, outpatient setting or inpatient setting. The only time that we do recommend that is for aerosol-generating procedures and when that's happening SARS-CoV-2 patient and in that context, yes.

>> Got it. Thank you. Thank you both for answering those questions. We got through registration. We'll take the rest of the time to answer those live questions we're seeing coming in, so I'll turn it over to you, Dr. Kallen, and see you in a little bit.

>> Great. Thanks, Liz. So we have a lot of questions which we're definitely not going to get to all of them, but we'll do our best to be brief and get to as many as possible, hint hint, Dr. Kuhar. So I don't know if Abby is around, but it looks like maybe the first one is for her if she's able to answer. If not, maybe David you could weigh in. There's questions here about the vaccines who were developed for COVID-19 and some questions about how -- whether or not they are effective to prevent the Delta variant. So I don't know, Abby, if you'd like to weigh in on that.

>> Sure, yeah, absolutely. So, absolutely, there is data to suggest that not only do they prevent people from getting sick, they also prevent people from dying and being hospitalized. And so, you know, it's not that the vaccines have gone from 100 to 0. There is slightly less ability of the vaccines to prevent infection than compared to previous variants of the virus, but in general, the protection for Delta from the vaccines remains quite good. It's just not as high as it used to be. And again, the key point for us as well is that it really does prevent hospitalization and death, so the severe consequences of illness are still mitigated by vaccines.

>> Great, thank you very much. David, question for you about breakthrough infections. For fully vaccinated folks who get a breakthrough infection, what are the recs about return to work?

>> Yeah, and so when it comes to infection control, you know, it is true that someone who is fully vaccinated who becomes infected might not shed virus as long, etc. Regardless, you're going to treat them in terms of work restrictions the same way if they have, you know, if they're one who tested positive, but who had no symptoms. You want to at least 10 days having passed since the date of their positive viral test. You know, mild to moderate illness, at least 10 days passing since that viral test and at least, you know, 24 hours since last fever that they're having improved respiratory symptoms. So I'd say it's not different than how you're treating other infections at this time.

>> Great. Thanks, David. Looks like a question from Facebook that I could answer quickly. Question is about the FAQs on the CDC COVID-19 healthcare website. So again, this is about the healthcare personnel. What FAQs are they going to be updated as the guidance as the answer to that is yes. They are currently in our clearance process, and though we expect those updates to be made fairly shortly. Not huge changes to those but just to kind of align them and make them a little clearer. Next question, David, is about people who are in -- who are infected with SARS-CoV-2 and Delta in particular who may shed virus for more than 10 days. Can you envision a formal recommendation from CDC to extend -- In this case, I'll say the use of transmission-based precautions for people or any thoughts on when that would be appropriate, thanks?

>> Yeah, sure. You know, at the moment, I would say that the duration of work restrictions remains the same, and, you know, so in general, we focus on that 10-day point. However, for people who have severe, you know, critical illness, these people are known that they can shed longer. The language I think that we've had has been, you know, that they're, you know, maintain precautions for at least 10 days. You can do it up to 20 days after they were, you know, first diagnosed or symptoms first appeared. And the other group that we often, you know, think about extending for are people who are, you know, moderately or severely immunocompromised, and these people might shed for longer. And when that's the case, these are people who might stay in precautions, and instead of waiting for a clear period of time, you may use a test-based strategy, which comes with a lot of sometimes challenges in interpretation but that you would serially test them until having two negative tests before lowering those precautions. So in those circumstances without a doubt, I think you do longer than those 10. For Delta, specifically, not at this time. I don't know that I necessarily see that coming, but we shall see what happens with the science.

>> Right, thanks, David. A question for you that is wondering about CDC's recommendations for COVID patients. Is that just for N95s when caring for the COVID patient?

>> And is that a CDC recommending N95, so the care of all COVID patients?

>> Yeah.

>> Ugh, so, ultimately, yes, CDC recommends using an N95 as a part of the whole personal protective equipment ensembles for caring for all patients with known or even suspected SARS-CoV-2 infections. So if you think they have it, use the appropriate precautions until you prove that they have something else, and if they prove that they had SARS-CoV-2, you were wearing the right equipment. And, remember, that is like Dr. Carlson had said earlier, a respirator, eye protection, gown, and gloves.

>> Right. Thanks, David. Also, another question for you about is there a preference for a PAPR over an N95 with a face shield for aerosol-generating procedures?

>> Yeah, this is a good question. So, ultimately, CDC is not differentiating using an N95 versus a PAPR, another type of respiratory protection device for an aerosol-generating procedure, but I understand why that question was asked. And for the group, a PAPR actually filters more of the air than an N95 respirator. It actually provides a higher level of respiratory protection. However, CDC isn't indicating a preference for that extra higher level of respiratory protection. [inaudible] an N95 is adequate.

>> Great. Thanks, David. We probably have time for a couple more. So, Abby, one for you. The person is asking about how do we protect non-COVID patients from staff?

>> Yeah, that comes back to source control, although I think that there's multiple layers to that, right? Some of it is about how you're screening your staff as they come in. Some of it is about, you know, having a culture amongst your staff that encourages people to stay home when they're sick. Some of it is, you know, making sure that you have policies and procedures in place to allow that to happen. But once the staff is in the building, the biggest thing you can do is have everyone wear a good, well-fitting mask, and obviously our preference is a medical mask, especially when interacting with patients, as Dr. Kallen had previously said, but that, you know, it keeps your respiratory droplets out of the air. And with that, it -- once those respiratory droplets are out of the air, they can't be breathed in by patients, and if they can't be breathed in by patients, then they're not, you know, going to get sick. So is it a perfect, you know, source control 100%, no droplets come out? No, that's really just not feasible, but the use of masks is quite good, and that data that we've seen in the lab is that it's quite good at blocking those droplets as long as it fits well.

>> Thanks, Abby. Liz, I think we're at time, so I think I will turn it back over to you.

>> Thank you all, and I wish we would go on for another hour and another hour more. The questions are so fantastic, but I want to take a moment to thank Doctors Kallen, Kuhart, and Carlson for joining us today and for you all for joining us as well. We appreciate you spending any time with us. We know your time is valuable. I do want to note that if you're interested in more information, feel free to see -- find out Project Firstline on our social media pages. You can search Project Firstline or checking us out on cdc.gov/projectfirstline. And a note to our folks on Facebook or those who are on Facebook themselves, a recording of this will be available and immediately on the Facebook page, and we'll work to get that on our website too as soon as we can. So thank you all for joining us today, and I hope you have a great rest of your week. Thank you.