A COVID-19 vaccination Dec. 15 at Stony Brook University Hospital.

A COVID-19 vaccination Dec. 15 at Stony Brook University Hospital. Credit: Raychel Brightman

In advance of Newsday's recent webinar with Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, our readers submitted more than 2,000 questions about the safety, efficacy and rollout of the COVID-19 vaccines.

Fauci was able to answer some of their questions during the 30-minute live discussion, which you can watch below.

Long Islanders submitted more than 2,000 questions to Dr. Anthony Fauci. He couldn't answer all of them, but he did answer a number about coronavirus vaccines and what we should expect.  Credit: Newsday studio

But for answers to many of the remaining questions, we turned to our local experts.

Below are responses from:

Polsky, Battinelli and Solomon answered reader questions during a Newsday Live webinar; Nachman, Hernandez, Pardo, Glatt, Donelan and Krilov responded in writing to Newsday to other reader questions.

Here are their answers, separated by topic, regarding everything from whether you should get the vaccine if you have risk factors to how long its protection may last.

If you have or had COVID-19 already

Theresa from Huntington Station asks: I'm a health care worker who recently got COVID from a patient. Is there a wait time for me now to receive the COVID vaccine? Will I get more of a reaction from it?

Dr. Bruce Polsky: So the people who have previously recovered from COVID who have been vaccinated tend to have a more robust kind of reaction to their first dose of vaccine than people who have not been exposed to the COVID virus previously. Kind of akin to the more pronounced reaction people get with the second dose of vaccine, which indicates that the immune system is already primed to respond. People who have recovered from COVID are getting that kind of response with the first dose of vaccine. It's not necessarily dangerous. It just means that your body has recognized the spike protein that it previously had experience with. So while not dangerous, it's to be anticipated.

The first part of the question is should she get vaccinated. And the answer is, I would say, yes. She should get vaccinated. The timing of the vaccine I don't think is particularly critical. I think once she's recovered and better, she should get in the queue to get vaccinated.

Jeanmarie asks via text message: I got vaccine No. 1 and was exposed the following day and tested positive a week later. Do I stay on track for vaccine No. 2? And Johnny asks: How soon can one take the vaccine after testing positive for COVID-19?

Dr. Susan Donelan: If someone was diagnosed more than 10 days prior, and has been asymptomatic for [at least] 24 hours, they may be vaccinated with the second dose. Since the currently available vaccines have a 21-28-day interval between doses, they can be revaccinated on time. Once one receives the vaccine, they should continue to wear a mask, observe social distancing, practice hand hygiene, etc.

A reader from Patchogue asks: I'm a long hauler. I still have a rash and breathing difficulties after having COVID and pneumonia. I have antibodies and will get tested again to see if I still have them. I work in a hospital as a nurse's aide and feel reluctant to get the vaccine. Do you think I should put off the vaccine at this time or receive it?

Dr. David Battinelli: Early on, we were talking about waiting 90 days. That was a little bit more about making sure that we were able to distribute the vaccine more broadly and not necessarily vaccinate somebody who might already have some lingering immunity, or some degree of immunity from having the disease. But with respect to the long haulers, either from having a continuous positive test as a PCR or disease that simply continues to run its course, mostly because of the secondary inflammatory effects and the organ damage that's done, we are recommending the vaccine. No question about it.

Arlo asks: If you've had coronavirus, should you wait until your antibodies are at zero before you get the vaccine?

Dr. David Battinelli: Once somebody allows you to get the vaccine because there's enough around and they've waited long enough, you should be getting the vaccine. We don't know anything about the antibody levels as to how protective they will or they won't be. And we won't know that information for many months to come.

Karen from Syosset asks: I contracted COVID in December — do you still recommend getting the vaccine? Or do I now have an immunity to the virus and, if so, for how long?

Dr. Nicolas Hernandez: As a COVID survivor myself, there is some natural immunity that can be acquired, but how well and long this will last is uncertain. Therefore, it is recommended that you get vaccinated when given the OK by your primary health provider, CDC guidelines and local health officials.

Dr. Salvatore R. Pardo: The current recommendation is to be vaccinated when eligible despite being previously infected. It is unknown how long a natural immunity lasts at this point, because something like this has never been investigated.

Gilda from East Yaphank asks: Do people who tested positive for the antibodies need the vaccine too? How long do the antibodies last?

Dr. Nicolas Hernandez: It would be recommended as there is a lot of variation in antibody levels and what is needed for protection against the virus. Personally, I lost all my antibodies after six months after having natural infection. However, what my long-term immunity will look like, that I am unsure of and therefore decided to take the vaccine due to my high exposure of the virus in my day-to-day workflow at the hospital. It’s like having an extra spare tire.

Joshua asks: If I have the virus, will the vaccine help me get better faster?

Dr. Bruce Polsky: So it's not recommended that you get the vaccine. This is not a therapeutic vaccine. It wasn't set up that way, and it wasn't studied that way. This is a preventative vaccine. It's to prevent from getting COVID. So there is no thought whatsoever that getting this vaccine is going to help you get over an active case of COVID. And we don't give it in that circumstance.

Lois from Southampton asks: If I get my vaccine but I unknowingly already have the virus will I get very sick?

Dr. Leonard Krilov: If you already have COVID, there’s no evidence that receiving the vaccine will make you sicker, but it is also unlikely to provide protective response since that takes time to develop — typically 10-14 days. However, getting vaccinated should provide protection against being reinfected with the virus in the future.

Diane from East Meadow asks: If you've had COVID, can you get the new strain?

Dr. Bruce Polsky: If you've had COVID previously, we do believe that you may be immune for a period of time. How long, we don't know. But best guess, it may be for several months after you've recovered from a case of COVID. We are beginning to see second documented cases of COVID from people who recovered, say, during March and April. And so it's clear you can get a second case of COVID. So that the immunity that you get from recovering from COVID is clearly not adequate to carry you all the way through. So that's number one.

As far as the new strain, the variant strain that's received so much attention, presumably you can get sick from the variant strain as well. We don't know how much immunity is provided from having recovered from COVID at all. And then, the most important question is, should you get vaccinated if you've previously had COVID? And the answer, to my mind, is a resounding yes. I think that the type of immunity that is likely to be engendered by a vaccine is likely to be more durable. We don't know, again, how long that durability will last. But likely to be more durable than the antibody response that is produced by recovering from a case of COVID.

Possible side effects

Michelle asks: What other side effects should people anticipate with the first and or a second shot?

Dr. Philip Solomon: Well, I can tell you from the studies, we've seen that the broad side effects are arm pain, which many people have gotten with other vaccines as well. Fatigue. Some people have developed fevers. Some of those side effects can be more prevalent with the second dose, as Dr. Battinelli and Dr. Polsky alluded to, and that's a sign that your body is creating an immune response. We call it side effects, but it's actually a good effect. It means that we're having a good effect of the vaccine.

I can tell you personally, I've gotten the first dose. I had a little bit of a sore arm for about 24 to 48 hours. Besides that it was completely anticlimactic experience. I had no other side effects and I felt very well.

If you have allergies or other health conditions

Teresa from Stony Brook asks: I have lupus, asthma and other health care risks. I am a cancer survivor. My husband is 77 and a stroke survivor. We both have multiple drug allergies. Is a vaccine available or in the works that would be safe for us?

Dr. Sharon Nachman: As per current guidelines, patients such as yourselves are expected to be able to be vaccinated with the current Emergency Use Authorization (EUA) approved products, but only after discussion with your providers.

Josh from Plainview asks: I have a few serious allergies. Will the COVID vaccine be safe to get, and if so, which one(s)? How will I find out?

Dr. Sharon Nachman: We have been vaccinating adults with allergies, but often asking patients with specific and severe allergies by history to wait 30 minutes after vaccination. The only true contraindication to receiving these current Emergency Use Authorization (EUA) vaccines is an allergy to a component of the vaccine. The components are listed in the EUA approvals.

Arlene from East Meadow asks: I heard that if you have an autoimmune disease that the COVID vaccine could cause a flare up. Is this true?

Dr. Nicolas Hernandez: There hasn’t been any conclusive data on this. You should speak to your primary medical provider and/or rheumatologist on the latest recommendations with respect to your specific disorder, but generally most immunocompromised patients are being encouraged to get vaccinated sooner than later to gain protection as the numbers continue to rise.

Dr. Salvatore R. Pardo: There is no data and the current recommendation is to get vaccinated. Having an autoimmune disease is considered to be immunocompromised, which makes the individual more susceptible to COVID-19.

Multiple readers ask: Is there any medication that you take for any condition right now that says that you should not be getting the vaccine?

Dr. David Battinelli: Again, it's much more about what your state of health is and speaking with your individual physician. But by and large, with vaccines, the medications are not a contraindication to get the vaccine.

Nancy asks: I was told by a doctor that although the vaccines are about 95% effective, for people with autoimmune issues like Hashimoto's, it would be less effective. What is the efficacy for people with autoimmune issues?

Dr. Philip Solomon: From what we've seen so far, we're recommending that people with autoimmune conditions get the vaccine. We've seen broad effectiveness from these vaccines so far. Obviously, you should discuss this with your individual health care provider, but we are recommending the vaccine be given.

Karen from East Setauket asks: Which of the vaccines is best for someone 65 to 74 with comorbidities such as diabetes, obesity, and high blood pressure? And also, whether you have a choice of vaccine, or whether you should favor one vaccine over the other. What's your advice?

Dr. Bruce Polsky: The question about comorbidities and age. Both of these vaccines, both the Pfizer and Moderna vaccines, both of the vaccines that are available today, were studied across a broad range of ages and the efficacy was very similar despite age. They work in the old and in the younger adult population, as well as people with comorbid conditions. So the idea is to get it. As far as which vaccine to get, when your number is called, get the vaccine that's available on that day, at that time, wherever you're going to get the vaccine. That's my advice. I wouldn't quibble over which vaccine it is. Just get vaccinated.

Evan from Forrest Hills asks: I suffer from seasonal allergies, food allergies, sinusitis. Any concern in taking vaccine? Jill from Ocean Beach asks: How should someone with severe nut allergies go about getting the COVID-19 vaccine? And Sharon from Hewlett asks: For people that have shellfish/iodine allergy, can they take the vaccine?

Dr. Aaron Glatt: There’s no clinical evidence that people with mild allergies need to avoid the vaccine. The American College of Allergy, Asthma and Immunology released guidance stating that people with common allergies are no more likely than the general public to have an allergic reaction to the Pfizer-BioNTech or Moderna COVID-19 vaccines. Allergists point out that, in general, vaccines are incredibly safe, with only around 1.3 anaphylactic reactions per 1 million vaccine doses administered. A study by the U.S. Centers for Disease Control and Prevention researchers revealed that the risk of anaphylaxis — a severe, potentially life-threatening allergic reaction — from the vaccine is extremely low.

Based on data from people who have received the first of the two recommended doses, only about one in every 90,000 people, on average, will experience this adverse reaction. When allergic reactions occur, they are typically in response to the inactive ingredients that accompany the vaccine’s active ingredients; therefore the FDA recommends that people with a history of severe allergic reactions to any component of the Pfizer-BioNTech or Moderna vaccines should not receive them.

Allergic reactions (including severe allergic reactions) not related to vaccines, injectable therapies, components of mRNA COVID-19 vaccines (including PEG), or polysorbates, such as food, pet, venom, or environmental allergies, or allergies to oral medications (including the oral equivalents of injectable medications) are not a contraindication or precaution to vaccination with either COVID-19 vaccine. The vial stoppers of these vaccines are not made with natural rubber latex, and there is no contraindication or precaution to vaccination for persons with a latex allergy. In addition, as the COVID-19 vaccines do not contain eggs or gelatin, persons with allergies to these substances do not have a contraindication or precaution to vaccination.

Concerns about pregnancy and fertility

Laura from Massapequa Park asks: Is it true that the new vaccines can cause infertility in women?

Dr. Nicolas Hernandez: I had the same concern. However, during the study there were participants who actually got pregnant unknowingly whether they had the vaccine at that time, so it is unlikely to cause infertility. However, more data will need to be compiled to be sure. You should speak with your OB-GYN, as data and the newest recommendations and guidelines will be updated frequently on the safety and efficacy of the vaccines.

Dr. Salvatore R. Pardo: I have not heard this and it is highly unlikely. In fact, some volunteers during Phase 3 trial became pregnant after taking the vaccine.

Dr. Philip Solomon: From just understanding how these vaccines work and how they produce an immune response, it is not consistent with even having a realistic ability to have that side effect. So there's just no evidence whatsoever that these vaccines should have anything to do with fertility issues.

Dr. Bruce Polsky: There's not even a theoretical basis from what we know about the way these vaccines work that there would be any effect on fertility, either short term or long term. It's just not the way these vaccines are set up.

Expanding who is eligible for the vaccine

Pam asks via text message: When can we expect people under age 65 and without pre-existing conditions to begin getting vaccinations? Early announcements, of course, said March. But now with such a dire shortfall and appointments booked through April just to cover those 65 and older, it seems that anyone who is younger will not be getting vaccinated much before July-October.

Dr. Susan Donelan: It is unknown what the current production capability is at this juncture [for the Pfizer and Moderna products], but one goal of the new administration is to produce and deliver 100 million doses of vaccine in the next 100 days. Dr. Fauci, who one would expect has further information regarding productivity potential, has stated that this is a doable goal. That said, the New York State Department of Health determines vaccine eligibility, allotment of vaccine supply to Point of Distribution sites across the state, and scheduling when appointments will be made available on the state eligibility site. It is also important to understand that we do not know when new vaccines will become available; should additional COVID vaccines be approved under an emergency use authorization, that will expand access.

Vaccinating children

Jen from Northport asks: When do you project the vaccine being available to children, and for what age ranges would it be safe?

Dr. Sharon Nachman: The clinical trials for ages 12-18 are enrolling from both Moderna and Pfizer. Other trials are ongoing. It may be a matter of weeks to months before we possibly have other opened studies in those age groups. Following that, all of the companies will need to open studies for younger children, eventually going down to children in the first year of life.

Dr. David Battinelli: In the studies that were conducted to date, in the Pfizer the cutoff was 16 years old and Moderna was 18 years old. So we don't have data on those younger age groups. We will have data emerging in the coming months about that, and we'll make recommendations to that. It's going to take us so long to get the vaccine distributed to all the other groups who are at the highest risk, and this is a group that is at a lower risk. So that's simply the way it's going to be. Certainly within the childhood ages, those patients who have underlying immune conditions, et cetera, once the vaccine does become available, will be the first to receive the vaccine.

Wendy from Syosset asks: Will the COVID vaccine be mandatory for children to go to school? For example, measles vaccine is mandatory. Why isn’t the flu vaccine mandatory for school children?

Dr. Sharon Nachman: This will be a policy question that each state will need to answer. I expect that discussions about mandatory vaccines will take place once we have enough supply of COVID vaccines and approval for several different products across the ages. It may be that next fall, college campus attendance will include a mandatory COVID vaccine, but only after supplies are available.

It's important to know that vaccines help prevent disease outbreak and deadly illnesses. And, community protection works, as we have seen with the recent measles outbreak, and the only way to combat these outbreaks is by protecting all the children in our community.

Alex from Holbrook asks: You have said we need at least 70% of the population and as much as 90% to achieve herd immunity. Since children whom the vaccine is not approved for make up 24% of the population, it seems even if 100% of the over-18 population received the vaccine we would not be able to achieve a level of normalcy. And since we know 100% won’t get it, and most parents won’t rush to get it for their kids even once approved, are we expected to continue life like this forever? Or what is the real outcome?

Dr. Sharon Nachman: I believe that when we have a vaccine in hand for all ages, and adequate testing of both symptomatic and asymptomatic populations, it will be much easier to understand exactly what is the number we need to hit to get sufficient community protection and be able to go back to "no masks needed.

Dr. David Battinelli: Yeah, it's going to take a little while to get us up to the numbers. And Fauci, others, I think everybody is sticking to the same numbers. You're going to need a minimum of 60% and preferably 70%, 75% immunity in order to do that. Since the children are not as susceptible to the disease, et cetera, they'll be less of a reservoir of the disease in that age group. So that's not really going to be as big a factor as it might sound. If there was another particular age group, slightly older, for some other reason, that couldn't be vaccinated upwards of 30%, then that would be an issue. But because this disease is not as prevalent in kids and therefore can't be passed around to others, it will not be as big a problem as you might anticipate.

The vaccines' effectiveness

Richard from Middle Island asks: How long does it take before the vaccine is fully effective in your system?

Dr. Leonard Krilov: It typically takes 10-14 days to build up immunity from virus vaccines. You need two COVID vaccine doses for the full effectiveness of approximately 95%, though some initial protection is expected following the first dose.

Jonathan from Oceanside asks: Are you ever going to be immune with this vaccination?

Dr. Philip Solomon: When we look at the studies, there are some subtle differences between the two vaccines, Pfizer and Moderna. But generally, what we're seeing is that immunity should be about 14 days after the second dose, is a safer way to look at it. And as we said before, 95% is a great number. It's not 100% So immunity does not mean that it's a get-out-of-jail-for-free card, that we stop physical distancing, that we stop masking. But in the trials, that's the data that we're seeing, that after the second dose, within two weeks.

Jill from Huntington Station asks: If a person takes the vaccine and does not get any reaction from it (no flu-like symptoms), does that mean that the vaccine will not be as effective for that person? Will he or she not get the necessary protection from it?

Dr. Nicolas Hernandez: No, everyone’s immune response is different with respect to initial doses and their respective reactions, but this does not disprove level of immunity. Just like the flu shot, some years you don’t feel anything and other times you have mild symptoms, but the immunity will still be there regardless and you should have protection against the virus regardless.

Dr. Salvatore R. Pardo: My understanding is that less than half get ‘reaction’ despite developing immunity. It doesn’t seem to have any correlation. For Moderna, in the FDA report published in December, the most common side effects were pain at injection site (91.6% of patients), fatigue (68.5%), headache (63.0%), muscle pain (59.6%), joint pain (44.8%), and chills (43.4%). And for Pfizer, the report said the most common reactions were injection site reactions (84.1%), fatigue (62.9%), headache (55.1%), muscle pain (38.3%), chills (31.9%), joint pain (23.6%), and fever (14.2%).

Fred from Huntington asks: How will I know that I am protected after vaccination, that I'm among the 95% for whom the vaccine proves effective? Without knowing, how will I then be able to live with less fear?

Dr. David Battinelli: You won't have specific information to say that you're absolutely in that 95%. Those are just the odds. So it is that leap of faith. That said, one of the other important features to this is, of the patients who were vaccinated in the trials, even those patients, those few patients, who in fact did get COVID, got a much, much less severe form of the disease. Very similar to other people who would be vaccinated and occasionally still get the disease. So that's the good news. But you do not have 100% certainty that you're going to necessarily not get the disease.

Dr. Bruce Polsky: I think it's also important to point out that in the clinical trials, the people who were participants who got the vaccine were sent back out into the community where there still was a fair amount of COVID going on, and there was more opportunity to get infected with the virus, and that's how we got the data. In the circumstance where everyone is going to be vaccinated, and we develop levels of herd immunity, whatever that percent ends up being, there will be less opportunity for the virus to find people to infect. So there will be less virus around, is the expectation based on other viral diseases. So that 95% number even becomes more significant once we have good vaccine coverage in the community.

Several readers ask: What happens if I don't get the second dose?

Dr. David Battinelli: The data so far — and again, we don't have huge amounts of data on people that didn't get the second dose — but it looks like you'll probably get about half the protection.

Andrew asks: If I get the vaccine, could I still carry coronavirus in some way, shape or form and give it to somebody else?

Dr. David Battinelli: We're not entirely sure. That is theoretically possible. As with other people who have been successfully vaccinated against other diseases, it's highly unlikely and extremely unusual. So we still think that that's the case. But we're not entirely sure. We are going with the belief that you will not likely be carrying the disease. But again, until herd immunity, until we get all the facts straight, we're not sure. But it's very, very unlikely.

Jerry from Old Westbury asks: I’ve gotten the vaccine twice, how likely is it for me to transmit the virus to my granddaughter if I’m exposed?

Dr. Nicolas Hernandez: Vaccines aren't perfect. Look at it as a second layer of protection. The chances are less once vaccinated to contract, but not impossible. Therefore, proper protective measures should still be taken until greater evidence-based medicine data can be sought.

Dr. Salvatore R. Pardo: It is unknown. My educated guess is that it is much lower than if you do not get vaccinated. We do know that the grandparent is typically more vulnerable than the grandchild, assuming both have a good baseline of health. That is why older persons have priority over younger persons. Congratulations on getting vaccinated! Tell you friends about your experience!

Cindy from Glen Cove asks: How long should the vaccine protect us from COVID?

Dr. Leonard Krilov: We don’t yet know. In more typical clinical trials, researchers would track vaccine patients for several years and have more certainty as to the long-term effectiveness of the vaccine. We do expect the COVID vaccine to have lengthier protection than the type of protection you get from an annual flu shot. The flu is a new strain every year, whereas with COVID, the world is seeing ‘mutations,’ rather than entirely new strains.

Elaine from Garden City asks: With new strains of the COVID virus coming out, how do we know that the vaccines being implemented now will work against the new mutated strands?

Dr. Nicolas Hernandez: Various statements have indicated that the vaccines currently provide protection against the majority of strains, new and prior, as the molecular defense of the vaccine helps break down the structure of the virus from a multifaceted aspect. More can be seen with respect to the efficacy of the vaccines as more get vaccinated and we see the lasting effects in the coming months to years.

Joan from Huntington and Diane from East Meadow ask: Will the COVID-19 vaccine that is available now be a preventive measure for the new strain of COVID-19 coming from the UK? And do you need to know which strain you have in terms of trying to figure out whether or not you need a vaccine?

Dr. Philip Solomon: Certainly, I think that's been on a lot of people's minds over the past couple of weeks as we've heard about different mutations. The simple answer is that as far as we know right now, the vaccine should be effective at preventing even these new strains that we're seeing as they're emerging for coronavirus. Now, certainly we are concerned and we need to be on the lookout as this virus continues to mutate. And it just underlines the importance of getting as many people vaccinated as quickly as possible. But the evidence we've seen so far is that both of these approved vaccines in the United States should be effective at preventing this new mutation and this new strain that emerged from the UK.

Louise from Oyster Bay asks: In the study following the vaccine, will people be tested frequently for antibodies to see how long the vaccine will protect the individual?

Dr. Sharon Nachman: In all of the clinical trials that have enrolled or are enrolling to date, everyone will be followed for 2 years with prespecified testing intervals looking at antibody titers. This allows for long-term safety assessment, and participants may also learn more about their own health as part of being in a study.

Joanne from Smithtown asks: Will the vaccination for COVID be effective as the virus mutates year to year or will we be at risk again and again?

Dr. Nicolas Hernandez: It is hoped that it will offer long term protection but only time will tell as we follow the original vaccinated cohort in the study. The experts who helped create this vaccine, however, carry decades of experience in vaccination production, research and immunity science.

Dr. Salvatore R. Pardo: This is an interesting question, because we are exposed to many different types and strains of viruses over our lifetime. The coronavirus is a common virus most associated with the common cold. However, the mutation of coronavirus, which resulted in COVID-19, was found to be much more contagious with a higher chance of death or significant long-term effects. So this vaccine is specific to this mutation, which should cover any small variances like the ones being reported.

Lori from Bethpage asks: I believe I will be getting vaccinated in either February or March as I am 65 and have an underlying condition. I will be attending a wedding in Colorado in June. I don't think there will be socially distant seating and it might be held indoors. I also don't know how many people will have been vaccinated. Will I be protected even if somebody should unknowingly have COVID? I will wear a mask and use hand sanitizer, but I am concerned.

Dr. Phillip Solomon: I want to just break that down to a couple separate issues that are kind of being addressed with that question. The first is, she's kind of asking, is the vaccine effective? The answer to that is, definitively, yes. We know that we're having 95% efficacy for broad age groups, including over the age of 65.

Now having said that, what we don't know is can you still be an asymptomatic carrier of this virus after you get the vaccine? Can you still have viral loads that transmit it? And the other piece of this is that 95% is not 100%. So when we see virus loads that are as high as they are right now, not only in Long Island but nationally, that's a big concern if you're going to events that are not going to be physically distanced, that are not going to be masked and that have high-risk exposures like eating, dancing, singing. So that's a long answer, but it's in the short way of saying: I would be very, very cautious with attending these type of events until we've reached a level of herd immunity. And until we've really decreased the prevalence of this virus across not only the country, but in these specific areas.

How clinical trials were conducted

Christopher from Garden City asks: How did the clinical trials take into account the behaviors of their participants? A participant who self-isolated and always wore a mask would automatically be less vulnerable to a contagion than one who attended parties and spent more time without a mask.

Dr. Nicolas Hernandez: From my understanding, the participants were randomly selected to add more validity to the trial. Therefore, as human behaviors would indicate, some were probably more lax on their interactions with the community versus others. The 100-day mark, however, is what impressed me most on those who were vaccinated versus those not, in [terms of] infectivity and antibody production. However, as mentioned before, we should all, vaccinated and not vaccinated, do our part to follow recommendations in wearing our masks and following protocols set by our health officials to help expedite the end of our current global health crisis.

Dr. Salvatore R. Pardo: You are correct, they did not make any recommendations. However, there were two groups, vaccine and placebo, and the administrators and recipients were blinded to which they got. The designers made an assumption that any and all behavior would be present in both groups and, as a consequence, cancel each other out. There was still a significant difference between the groups regardless if they wore a mask or not.

The different vaccines

Jeanne from Albertson asks: Is it recommended that the second dose be the same as the first? If a person takes Pfizer for the first, can the second dose be Moderna?

Dr. Philip Solomon: It's really important that people know they need to stick to the same vaccine they got the first time. That is what the science dictates. That's what the trials dictate. So if you have your first dose of Pfizer, you're locked into that second Pfizer dose. If you get the first dose of Moderna you're locked into that second dose of Moderna.

Carol asks: What are you guys hearing about the AstraZeneca vaccine? Is that going to be coming down the line? What are you guys hearing on the inside?

Dr. Bruce Polsky: We expect that it will be coming eventually. We know that it's more advanced in other countries at the moment. It's not been formally reviewed yet. I mean, it's certainly hoped that it will come along. But again, these things require the kind of rigorous review that the Pfizer and Moderna vaccines went through, with the FDA, with the independent advisory panels that made the recommendations for the emergency use authorization. And we're certainly hopeful that not only the AstraZeneca, but the Johnson & Johnson and other vaccines will be coming along. But it's going to require all of the steps that brought us to this point with the vaccines that are currently available.

Donating blood post-vaccinations

Don asks: Can people give blood after being vaccinated? Would that be effective in treatment as well, since presumably we'd have antibodies?

Dr. David Battinelli: Yes, sure. So that relates to the idea of convalescent plasma that we had early on. That we would get plasma and pool it together to get certain types of antibodies together. And then perhaps give it to a patient who was sick, and would that help. Unfortunately, it does not help. And it wasn't a bad idea to try. We didn't really have, and still don't have, very effective antiviral therapies. So that's actually not going to be something that we'll be moving forward with, especially now that we have vaccines. Much, much more effective to be vaccinated.

Returning to normalcy

Lorne from Massapequa asks: Will it ever be safe to not wear a mask in public in the U.S.? In a foreign country?

Dr. Leonard Krilov: Masks may become ingrained in our culture for the foreseeable future, and that may be a couple of years — or possibly longer. If masks are no longer needed to protect us against this strain of COVID, people may continue to wear them because they’re effective against other viruses like the annual flu.

Harvey from Old Bethpage asks: After I get the vaccine, can I go to the gym and eat inside a restaurant? I am 80 years old.

Dr. Philip Solomon: Harvey, I think that his question and what he's missing is the same thing that so many of us have been missing over the last year. The good news is that there seems to be a light at the end of the tunnel here, as we've said. If we can reach herd immunity and we can really decrease the amount of virus in the community, that could be a reality, hopefully, by the end of this year. But I would not say that getting the vaccine would mean that you have a get-out-of-jail-for-free card and start doing these activities without needing to take the proper precautions. So Harvey, I would not recommend doing high-risk activities like indoor dining and going to the gym just because you're vaccinated yet.

Denise from Lindenhurst asks: Will the virus permanently impact our social behavior post-vaccination?

Dr. Nicolas Hernandez: There definitely is an impact already, but how it evolves will determine how the curve becomes reflattened with herd immunity and public health guidance going forward in the coming months to years.

Dr. Salvatore R. Pardo: It is hard to know what the future will bring, but my guess is that we have been so affected by this pandemic, it will be hard to ignore any feelings towards new biological threats moving forward. I firmly believe us returning to normalcy will not be a matter of IF, but WHEN. This is why a successful mass vaccination effort will be the key to a return to normal socialization.

Ken from Plainview asks: Being that many of us have been living in a bubble since March, is our general immunity to other bugs severely diminished, so that when we start to re-socialize, our chances of getting sick from many, many viruses and bacteria will elevate?

Dr. Bruce Polsky: Well, I think the answer to that is most likely no. That once we emerge from our bubbles, we'll have the same immune endowment that we started with when we went in.

Dr. David Battinelli: It was a relatively short time, but picking up on what we're talking about, we shouldn't forget we have not seen flu this year. We at Northwell haven't had a single hospitalized patient with the flu the entire time. And other places in the world where the flu normally moves, you know, from west to east, similarly. So for these types of infectious diseases, especially for diseases you don't have any immunity to, these practices work really well.

A reader asks: Are older people in nursing homes going to be better able to handle reintegrating with their family members, reintegrating with other people from outside of the nursing home as these vaccines go in? Are they going to be better off?

Dr. Philip Solomon: Well, I think there's no doubt that when we can start having increased socialization, increased activities and just increased engagement for our older adults, particularly those who are in long-term care facilities, it's going to be an improvement in overall well-being. It's certainly something that we've seen throughout this pandemic. Mostly, even for patients who never contracted COVID but still had a significant decline in functional status from that lack of social engagement. And I know that all of us are ready for that, when the time comes.

What we know about the virus

Brittani from Lake Grove asks: Is blood type O less likely to get COVID over those with other blood types? Are O at a lower risk?

Dr. Leonard Krilov: We don’t yet know why, but statistically those with Type-O blood are experiencing less severe cases of COVID disease. We suspect it could be that there are different antibodies associated with different blood types. Type-A and Type-AB are seeing higher correlations to more severe cases of the disease.

Linda from North Woodmere asks: If you have had COVID-19, can you still get the new strain of the virus?

Dr. Leonard Krilov: Yes. Technically, there are "mutations" of COVID-19, rather than entirely new strains as we see every year with the flu. While there is likely some cross-protection from one COVID-19 virus to another, you can get a repeat case of COVID — and that probably includes the newer mutation.

If I'm vaccinated and I have it on my hand, can I pass it to somebody?

Dr. David Battinelli: It's not likely that this is carried successfully on environmental surfaces in the first place. But if in fact you were to touch somebody who had the disease actively, with a wetness or something, and then were to touch somebody's eyes, yeah, you could transmit the disease, probably, that way, even though you might not catch it yourself. So all the more point that the other doctors have mentioned, which is, keep the mask on. Do as best you can on distancing, careful hand hygiene, until this thing goes away.

Jeannine from Levittown asks: Does chlorine in pool water kill COVID?

Dr. Leonard Krilov: Probably. Chlorine kills many viruses and likely would inactivate SARS-CoV-2 in the water, but the bigger question is ‘What are you doing at the pool?’ If there are crowds, chlorine in the pool may not limit your exposure to COVID.

Ken from Cedarhurst asks: Is a prayer service that's held in outdoors safer than one that is held indoors, assuming that in both cases people for the most part socially distance and wear a mask? And if so, how much safer?

Dr. Philip Solomon: Well, I think, first of all, we do know that indoor activities certainly carry higher risk than outdoor activities. I think that we've seen that. … Despite the lower risk outdoors, we do know that some of these activities can still carry a lot of risk. And especially something like a prayer service, where people might be singing, we're not sure how well distancing always can be. There's still a certain level of risk there. I think we need to be aware that whether you're indoor or outdoor, there's a certain level of risk that probably is carried by going to a religious service.

A reader from Babylon asks: My husband is being treated with radiation for cancer of the prostate. If he came in contact with a person who a few days later tested positive for COVID and both of them were wearing masks, should we be concerned?

Dr. David Battinelli: If you've come in contact with a known COVID-positive person and have had a substantial exposure, you should be isolating for the appropriate amount of time and potentially testing yourself somewhere around day seven or so, to see if it's been transmitted. If both people had masks on, there was no touching, you were socially distant, the likelihood is lower. And we know that proper precautions should be taken.

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LIers submitted more than 2,000 questions to Dr. Anthony Fauci for a Newsday Live conversation earlier this week. He couldn't answer all of them, so local doctors pick up where he left off. Sign up for COVID-19 text alerts at newsday.com/text. Panelists include Dr. David Battinelli, SVP, Chief Medical Officer Northwell Health; Dr. Philip Solomon, Director of Geriatric Education and Clinical Integration and Associate Program Director for the Geriatrics Fellowship program at Northwell; and Dr. Bruce Polsky, Chairman of medicine at NYU Langone Hospital-Long Island.