CNN  — 

The new Omicron variant has been spreading rapidly throughout South Africa, and it has now reached numerous locations around the United States. Preliminary data indicate that the vaccines may not be as protective against this newest coronavirus variant as they were against previous variants, though a booster dose appears to increase protection.

Should all this information change how we think about December holiday parties? What factors should we consider in deciding whether to attend? If you are organizing an event, how can you help to reduce the risk of Covid-19 spread?

I discussed this with our expert, CNN Medical Analyst Dr. Leana Wen, an emergency physician and professor of health policy and management at the George Washington University Milken Institute School of Public Health. She is also author of a new book, “Lifelines: A Doctor’s Journey in the Fight for Public Health.”

CNN: Should people change their holiday gathering plans because of Omicron?

Dr. Leana Wen: Not at the moment, no, at least in the United States. That’s because the dominant US variant, by far, is still the Delta variant. Omicron has been spreading rapidly in South Africa, but it has not yet outpaced Delta here; though it’s possible this could occur in the coming weeks and months.

I’m not saying that people should throw caution to the wind around Covid-19, only that the risk decision should be driven by what we are worried about right now, which is primarily the Delta variant. And there is plenty to be worried about there. Infections are on the rise, as are hospitalizations and deaths. People attending holiday gatherings should certainly be aware of the risk of Covid-19 spread whenever they are around others, in indoor settings.

CNN: What should people consider in deciding whether to attend a holiday party?

Wen: People should consider three factors. First, what is your medical circumstance and the circumstances of people in your household? If everyone in your household is fully vaccinated and boosted, that’s a very different situation than if no one is boosted and some family members, like younger children, are unvaccinated or have only had one dose.

Second, what precautions are being taken at the party? I’d feel a lot more comfortable if everyone is required to be vaccinated, and ideally is also boosted, and if proof of vaccination is asked at the door. Is the event indoors or outdoors? If it’s entirely indoors, will testing be required? Same-day home testing for all attendees will add an additional level of reassurance.

One important caveat to keep in mind is that events serving food and drink may say that they require masks, but unless you plan to keep your mask on the entire time, regardless of what others are doing, you should treat this as if the event does not require masks. That means this would be considered high risk unless some of these other measures, like required vaccination and testing, are also there.

Third, what is the value of the event to you? There may be a higher-risk event that you decide to go to not because of its safety, but because it’s so important to you. The wedding of a close friend, a memorial service, a family reunion. These might be of such high value to you that you are willing to take on the risk.

Remember, though, that risk is additive. Going to one higher-risk event doesn’t mean you should go to others. If you decide some higher-risk events like weddings and funerals are really important to you, you should consider skipping others (the office Christmas party or friend’s New Year’s get-together) because these events are not as crucial as others.

CNN: What if you don’t know what precautions are going to be there?

Wen: Ask the organizer. Depending on your relationship, you may even suggest ways to make the event safer from a Covid-19 perspective. For example, if the weather is nice, perhaps some parts of the gathering can be held outdoors. Perhaps the host is willing to consider required vaccination or testing upon your suggestion.

CNN: If you are the host, what additional steps can you take to reduce the risk for guests?

Wen: Again, I would highly recommend required vaccination and boosting with verification. For indoor, maskless events, I’d highly recommend same-day testing as well.

I’d also encourage early, clear and consistent communication. Tell your guests well in advance so that they have time to get their booster doses or procure rapid home tests. Some guests may be reluctant to ask you but will be very relieved to know that you have taken so many safety measures into account. Some may also be worried about the new variant. Continuing to communicate regularly will be important leading up to the event.

CNN: What if you require vaccinations, but you know some people who are planning to come are unvaccinated or are unwilling to share their vaccination status?

Wen: I think you have three options. First, you could try to change the setting so that it’s safer to accommodate these unvaccinated people. There are parts of the country where an outdoor event might still be feasible.

Second, you could still hold the event, but inform the other guests that vaccination is not required. I believe you have an obligation to tell guests that there are some in attendance who may be unvaccinated. That allows people to make the decision not to attend if they wish.

Third, you could continue to enforce vaccinations, which means some unvaccinated people won’t be able to participate. Whether you choose to do this depends, in part, on how many others would not come if vaccination were not required.

CNN: What if you decide to go to an event, but it turns out that safety protocols are not being followed as promised?

Wen: You have at least four options. First, you could talk to the host. If vaccination cards are not checked at the door, but it’s a small gathering and the host is confident everyone is vaccinated, that could provide needed reassurance for you. If you thought the event was outdoors but it’s actually in an enclosed tent, perhaps the host could open one or more of the sides to improve ventilation.

Second, you could protect yourself to the best of your abilities. Say that you thought this was a vaccinated-only event, but it turned out not to be. Even if others are unmasked, you could wear a high-quality mask.

Third, you could decide that you are OK with the lower level of precautions. If you go with this route, be sure to take extra care before visiting vulnerable relatives — wait a few days after the event and then get tested before going to see an elderly family member in a nursing home, for example.

Then fourth, of course, you can always decide to leave. This is about your physical health and also about your emotional and mental well-being. In some circumstances, it may be advisable to leave an event that would otherwise leave you stressed and worried.

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CNN: Do you have any other advice when thinking through holiday gathering decisions?

Wen: Stay flexible. Check the Covid-19 infection rates in your area, just as you would a weather forecast. Keep an eye on Omicron and, importantly, Delta. Be ready to modify plans, though I wouldn’t cancel on account of the new variant just yet.