Can Covid Winter Be Merry and Bright? We Asked the Experts.

Americans are headed into yet another Covid winter and holiday season. In many ways, the situation looks brighter than last year: Most adults are vaccinated, young children can now get shots and, hopefully, people can get their hands on rapid tests. But new risks emerge as more Americans are likely to try to have a “normal” holiday season.

We asked three experts from different disciplines to respond to a selection of questions from readers about how to think about risk and navigate another Covid winter. Their answers have been lightly edited for length and clarity.

The experts

• Dr. Linsey Marr, an engineering professor at Virginia Tech, where she studies airborne transmission of viruses.

• Dr. Juliet Morrison, a virologist at the University of California, Riverside.

• Dr. Jennifer Nuzzo, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health.

Who should be on the guest list?

How do you decide if you can host an event or not, like a Christmas party? Assuming everyone attending is an adult and vaccinated, can we have a big party similar to what we might have done two years ago, or should it be much smaller? Or is it just irresponsible in any event at this point?— Steve Toth, Chicago

My unvaccinated brother-in-law has had Covid-19. He was hospitalized, recovered and now claims he is immune and wants to visit us at Christmas. We are all vaccinated, but I am reluctant to host him or anybody else, and am afraid of indoor gatherings. Am I being unreasonable?— Irene LeHerissier, Catania, Italy

Linsey Marr: The safest way to have a large, indoor gathering of vaccinated people like in the before times (i.e., without masks and other precautions) is to have everyone take a rapid test before entering the event. Breakthrough infections and Covid spread can occur, and rapid tests can help catch anyone who might be infectious, thus minimizing the chance of transmission at the event. You can further reduce the risk by improving ventilation and/or air filtration.

Jennifer Nuzzo: It depends on your personal risk tolerance. I feel relatively comfortable hosting and attending small gatherings of adults who are fully vaccinated. This is in part because I feel well protected from serious illness by having been vaccinated and because if I were to become infected, I could handle a mild illness. I also feel comfortable doing this because I live in a relatively low transmission area. For people who want added safety, I agree you could use rapid tests on the day of the event. When I have people over, I open windows or bring air filtration machines into the rooms.

Help, the kids are coming inside!

If our child, 9, and a cousin, 10, have each received one dose of the vaccine two weeks prior to Thanksgiving, is it safe for us to eat indoors? There will be about 20 guests, all vaccinated, and the 65 and older crowd have all received boosters.— Julie Lewis, San Francisco

Marr: I’m glad to hear that the children and all guests are vaccinated. As the kids will not be fully vaccinated until two weeks after their second shot, I think some care is warranted, especially because some attendees are 65 and older and thus at greater risk of more serious breakthrough infections. You could have the kids wear masks, eat quickly and stay away from the older adults when eating.

Nuzzo: This Thanksgiving, we will be gathering with friends under similar circumstances. All of the adults will be fully vaccinated. The only attendees who aren’t fully vaccinated will be my young children who will each have one dose. It’s not zero risk, but I feel relatively comfortable with this scenario, particularly because we live in an area where case numbers are relatively low. But if you are gathering somewhere where community prevalence of infection is high, that increases the chances that someone at the gathering will be infected. Rapid tests and masks would further reduce the risk in all scenarios.

Do I really need a booster?

I’m fully vaccinated (two doses of Pfizer) and am contemplating getting a booster shot. My only concern is whether it’s ethical for me to do so while so much of the world is still not vaccinated. Would I be grabbing a dose that could have been put to better use, or would my dose simply go to waste if I didn’t use it? I’m a healthy middle-aged man with no high-risk factors or underlying conditions. I also work mostly from home and still wear a mask when I go to my workplace and when shopping, as a courtesy to front line workers. — Robert Sinkovits, San Diego

Juliet Morrison: Since you work from home, have no underlying health conditions and are below 65 years old, you do not need to rush to get a booster. Your two doses of Pfizer should protect you against the Delta strain and other variants of concern. However, if you are still worried and are eligible for the booster, you should absolutely go for it. They may soon be recommended for more people. Your rejected dose is unlikely to end up in the arm of an unvaccinated person because of the logistical and structural limitations of our health care system.

When should I mask up?

I know for a fact that not one person from either family gathering my wife and I are attending on Thanksgiving will be wearing a mask. Most people in my extended family are vaccinated, but my wife may be the only one in her entire family. We have received our Moderna booster shots. Do we have to wear masks? If no one else is wearing them, will it even do any good? — Scott P. Erskine, Ohio

Marr: It sounds like you will probably be spending several hours indoors with numerous unvaccinated people. This is a risky situation in terms of transmission, especially if guests are coming from areas with high transmission. If you’re willing to accept the risk of minor illness and a smaller risk of a more severe case, then you do not need to wear a mask. If you wear a mask, it will provide some protection, even if no one else is wearing a mask. A high-performance mask such as an N95, genuine KN95, or KF94 provides excellent protection. Other ways to reduce your risk are to spend as much time as possible outside, or turn on the kitchen and bathroom exhaust fans and sit by an open window. Even just a few inches will make a big difference.

Nuzzo: In navigating risks, so much of what is involved is personal risk tolerance and judgments about benefits. Though I’m generally more comfortable in social gatherings where the adults are vaccinated, if the event were important to me, I may be willing to assume some additional risk from being around unvaccinated people. In this scenario, I’m much more worried about the unvaccinated people contracting the virus from other unvaccinated individuals at the gathering because they will be less protected from the consequences of an infection than vaccinated people. You could use rapid tests, particularly for the unvaccinated individuals, to increase safety at this gathering and you could also wear masks.

I really need to get out. Or do I?

Is it safe for me — 74, vaccinated, boosted and in generally good health — to travel to a state with a lower rate of vaccination than my own? I’d love to go somewhere warm this winter, but not at the risk of my health.— Barbara Sloan, Conway, S.C.

Covid deaths in October in our nine-county area were the second highest (monthly total) since the pandemic began. Vaccination rates are around 60 percent. Should I stop going to restaurants and go back to self-quarantining again?— Robert Palmer, Le Sueur, Minn.

Nuzzo: People in public health tend to avoid using the word “safe” because it’s really relative — some things are safer than others, but nothing is zero risk. Since you are vaccinated and generally healthy, I think it’s perfectly reasonable for you to travel. If you want to be safer while doing it, pick somewhere to go where the community prevalence isn’t accelerating. You can also mask in indoor spaces and avoid crowded places to further reduce your risk. But the beach is a great place to relax in the winter because you get to spend more time outdoors where the risk of transmission is quite low. Have fun!

Morrison: Whether you choose to self-isolate depends on your level of risk. If you are fully vaccinated, in good health and do not work or socialize in areas with high case numbers and low vaccination rates, you are at low risk for infection and disease. You can feel comfortable traveling if you take some additional precautions. The safest thing to do if you are in situations where you don’t know the vaccination status of those around you, is to wear a mask and distance. It’s even safer if you socialize outside. If you are planning to travel on a plane, bus or train, keep your mask on while in those enclosed areas.

What do I do with my unvaccinated kids?

I have unvaccinated twin infants. Should we be taking the same precautions now as we did before we were vaccinated? — Jess Greco, Dobbs Ferry, N.Y.

Marr: The answer really depends on your own level of risk tolerance. I wouldn’t recommend taking your babies into a risky environment, such as a poorly ventilated indoor space with other unvaccinated people, but you could reasonably ease up on some of your own precautions — if you ever have a moment away from your babies — since the vaccine means you are less likely to become infected and transmit the virus. When thinking about risk for kids this age, a good comparison might be how you respond to other respiratory viruses they are at risk for.

Nuzzo: I agree that risk tolerance is important here, as is your infants’ particular health situation. But I do think your being vaccinated makes things a lot easier for your family because it lessens (though does not fully remove) worries that you’ll pass something along to your babies. The most important thing you can do to protect your infants is to make sure that the adults in their lives are vaccinated. If you’d like to further reduce risks, you can also avoid or wear masks in crowded indoor spaces. I personally felt comfortable doing more activities once my husband and I got vaccinated, despite having two unvaccinated children. But we prioritized activities that were particularly beneficial to our family and avoided potential exposures that we didn’t think were worth it. If our children had underlying health issues, I would have made those risk/benefit decisions diffe

What should I do if I’m higher risk?

My husband and I have had three doses of Moderna, the last one being the booster. My husband had a heart attack and six bypasses five years ago. We eat healthy, are trim and exercise daily. Is it safe for us to go to the theater, movies or concerts? Should we wear a mask? — Bonnie Popdan, Lancaster, Pa.

Nuzzo: If I were immunocompromised, I would probably continue to avoid crowded indoor spaces in areas where community transmission is high. I would speak to your provider to understand how much your husband’s health history puts him at risk, despite his current vaccination status. But generally speaking people who aren’t immunocompromised would be well protected from serious illness after receiving three doses of vaccines. But if you want to reduce the chances of your becoming infected, you should wear masks in these settings.

How do breakthrough cases fit into the picture?

I am curious about how the timeline for breakthrough cases and cases of those unvaccinated varies, if at all. I’m trying to figure out levels of risk to come up with the best time and method of testing before family gatherings. — Lee, Brooklyn, N.Y.

Nuzzo: These days I recommend that people use rapid tests because lab-based tests have been so unpredictable in terms of when you will get test results back, especially before the holidays due to demand. While the performance of rapid tests is improved through repeated testing, even a perfect test is only an assessment of your status at the time the test was performed. So it is most important that you test on the day of the gathering. But you can also test a couple of days before to improve the reliability of your test results.

Morrison: Even though the vaccines are highly efficacious, a subset of fully vaccinated people will get infected and develop Covid-19. The good news is that the majority of breakthrough cases are mild and resolve more quickly in vaccinated people because their immune system is set to respond quickly and clear the virus faster. In my social circle, everyone is vaccinated (except for those who cannot be), and we mask indoors and in crowded areas so we are at very low risk to contract the virus. Before we gather as a group, anyone who has potentially been exposed to SARS-CoV-2 takes a rapid test a day or two before the event. If they test positive, they stay home.

Is another variant coming?

How much concern should there be about a new, more dangerous variant, given that most of the undeveloped world is being neglected and a sizable proportion of U.S. citizens have not been vaccinated yet? — Michael James Wilson, Pennington, N.J.

Nuzzo: It’s a real and reasonable concern. Improving access to and uptake of first and second vaccine doses is essential for ending our worries about this pandemic. Aside from being in our pragmatic best interest, it’s also the morally right thing to do, as increasing the number of people who are vaccinated helps to limit the number of preventable deaths that this virus will cause.

Morrison: Viruses can only mutate when they replicate, and they can only replicate inside cells — unlike microbes such as fungi and bacteria. As such, if there are unvaccinated people in which SARS-CoV-2 can replicate, this virus will continue to acquire new mutations. It’s not a matter of if, but instead when, a new variant will arise. That’s why we need to stop transmission in its tracks. We are currently failing to do so. Less than 5 percent of the people in low-income countries have received at least one vaccine dose. We need to vaccinate the whole globe if we are to prevent the emergence of new variants. It is the moral and scientifically sound thing to do.

Are better times coming?

What would be a low estimate of infections going into the winter? Is there any good news on the horizon? — Veronica Hansen, Bellingham, Wash.

Marr: The number of new cases has leveled off, and with winter and holiday travel and gatherings coming, I fear that we may be stuck at this stage for a couple of months. The good news is that kids ages 5 to 11 can now get vaccinated. That will not only help protect them, but it will also help reduce community spread of the virus. That said, the trajectory of the pandemic has been hard to predict, so we need to be prepared for the unexpected.

Morrison: There are new Covid-19 vaccines and therapeutics that are close to being approved. For example, Novavax has filed for emergency use authorization for its vaccine with the World Health Organization and other countries. This vaccine may be more appealing to people who were hesitant about taking the newer technology vaccines, since Novavax’s vaccine is based on more “traditional” vaccine technology. That means that more people will get vaccinated and transmission will decrease. Additionally, new studies are coming out that show efficacy for several new and repurposed drugs. Pfizer recently reported that their new drug reduced the risk of hospitalization or death from Covid-19 by 89 percent.

Nuzzo: While I think we may see a rise in cases in the coming weeks, I don’t expect that the post-holiday surge of cases will be nearly as bad as it was last year. The really great news is that we have more tools to protect ourselves. Vaccines are now widely available for teens and adults and they will become increasingly available for children ages 5 to 11. There are likely to be more rapid tests available to guide our decision making about whether and when to gather. I really do feel that we are in a much better place now then we were this time last year.

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