Many grandparents have one goal in mind this winter: Get vaccinated so they can see their children and grandchildren again. But is that safe if their younger family members have not yet been vaccinated? Older adults are one of the priority groups for vaccination. After health care workers and nursing home residents are vaccinated, the US Centers for Disease Control and Prevention has said that individuals 75 years old and older – along with other categories of essential workers – are next in line for vaccines. In an increasing number of states, seniors are already getting vaccinated or will be vaccinated soon. What happens when older adults are vaccinated, but their children and grandchildren aren’t? Can grandparents now safely visit with family, or are there still certain precautions they need to take? We turned to CNN medical analyst Dr. Leana Wen, an emergency physician and visiting professor at George Washington University Milken Institute School of Public Health, for guidance. CNN: Let’s start with timing. When does the vaccine give you protection after you’re vaccinated? How much protection does it offer? Dr. Leana Wen: Both the Pfizer and Moderna vaccines require two doses to give optimal protection. There is probably some level of immunity after one dose, but we don’t know how complete the protection is and how long it lasts. The clinical trials were run with two doses, and you should definitely get both doses. Make sure you get the second dose of the same vaccine as the first (so if you got the Pfizer vaccine the first time, get the Pfizer the second time, too). Follow your provider’s recommendations about when to get the second dose. The second dose of the Pfizer vaccine is typically given after three weeks and the Moderna after four weeks. After the second dose, it probably takes another two or three weeks to develop the optimal degree of immune protection. Let’s say you’ve received one dose of vaccine. After a week or two, you have some level of immunity, but you could certainly get Covid-19 if you’re exposed to the coronavirus. A few weeks after the second dose, studies have shown that the vaccine efficacy is approximately 95%. That’s a very high level of protection but it’s not 100%. So even after getting both doses of the vaccine, you could still get Covid-19, but your chance is much lower. And if you did get it, according to what we know from clinical trials, you’re probably going to have less severe disease than if you didn’t get the vaccine. CNN: Once an older adult has received the second dose, and it’s been three weeks, can they visit their grandchildren? Wen: Maybe. The answer is not as simple as saying that someone who is vaccinated can get back to pre-pandemic life. Here’s why. First, the vaccine is not 100% effective. There is still a chance that someone who has received the vaccine can get Covid-19. This is particularly true as there are many parts of the country that are undergoing substantial surges of infection. The rate of community transmission is very high, so there is still going to be a chance of contracting coronavirus even after getting vaccinated. Second, the vaccine has not yet been shown to reduce transmission of the virus. We don’t know if people who are vaccinated could still be carriers of the virus, even if they don’t get sick. That means you could be protected yourself if you get exposed to someone with coronavirus, but you could still be a carrier of the virus. When you get together with your loved ones, you could spread it to those who aren’t vaccinated. If your grandkids live in the area, you could definitely safely see them outside, 6 feet apart. If you want to see them indoors, there is going to be some level of risk. That risk will be much lower than if you were not vaccinated, but the risk is still going to be there to you. And you could still be a risk to the unvaccinated members of your family, as you could be an asymptomatic carrier who transmits to them. If you really want to spend time with the grandkids indoors, the safest way to do this is still for everyone to quarantine for at least 10 days and lower their risk during these 10 days. Quarantining for seven days and a negative test is an option too, but everyone also has to do the quarantine — a negative test alone is not enough. CNN: What’s the point of the vaccine if I still have to quarantine before seeing people? Wen: From what we know so far through clinical trials, the vaccine does provide a lot of protection. It will also bring you peace of mind. It reduces your chance of getting the virus and getting severely ill from it. We know that elderly individuals and those with chronic medical conditions have a much elevated risk of severe illness and death, and the vaccine will substantially reduce these outcomes. Because you do have much reduced risk as a result of getting the vaccine, it’s a personal judgment as to what activities you most value and may want to consider bringing back. Maybe it’s really important for you to hug your grandkids. If you do this, recognize that it’s not a zero-risk activity, to you or to them. It’s still best for everyone to wear masks while hugging, and to do this outdoors and ideally with faces turned away from one another. Maybe it’s really important to you to have a meal together. I’d still advise different plates, no buffet-style dinner, and to eat outdoors rather than indoors. If you live away from your grandkids, you could consider traveling to see them if it’s something extremely important to you. Of course, continue to abide by all the social distancing and masking rules. And know that you still have some risk of both acquiring the virus as well as transmitting the virus. Please keep in mind that risk adds up. Getting the vaccine reduces your overall risk, but that doesn’t mean you should now do every high-risk activity. Maybe you are now choosing to have dinner with your grandkids and to hug them. Don’t also decide that you should go to an indoor restaurant with your friends and go to a crowded movie theater. You should still be trying to reduce risk in your life as much as you can. CNN: What if I have friends who got the vaccine, too? Can I see them without my mask, indoors? Wen: It’s probably pretty safe to see others who were also vaccinated, after everyone gets both doses and waits a few weeks. In a way, you could see getting the vaccine like being in quarantine. If both parties have been in quarantine, it’s probably pretty low risk to safely see one another. In the same way, if both parties have received the vaccine, you can probably see one another relatively safely. But because we don’t know if vaccinated people could still be asymptomatic carriers, if you participate in risky behaviors, you could infect others you have close contact with who aren’t vaccinated. Let’s say that you live with people who have not yet been vaccinated. You wouldn’t want to engage in activities where you could potentially acquire coronavirus and then transmit it to others. That includes seeing other people who are vaccinated, but not wearing a mask — based on what we know now, they could have the virus and pass it onto you, and you could pass it onto the people you live with. An abundance of caution is still a good idea. CNN: What is it going to take for us to be able to socialize as we did before Covid-19? Wen: The end of Covid-19 could come once we get to herd immunity. We don’t know exactly how many people will need to develop immunity to get to this point, though experts like Dr. Anthony Fauci estimate that this could take up to 85% of the American people to be vaccinated. At that level of immunity in the community, coronavirus would have nowhere else to spread and could essentially die out. With the speed of vaccine rollout so far, getting anywhere close to that level is going to take some time. Also, clinical trials are just getting started on children, so it will take probably until summer or fall for children to be vaccinated. We have to frame getting vaccinated differently. Vaccination is not a “do whatever I want” pass, but rather another tool to reduce our risk. Wearing a mask is another such tool, as is social distancing, and we want to keep up using as many tools as we can to protect ourselves. Getting the vaccine helps our community to allow us to achieve herd immunity faster. And it does also give us license to do a few more things that we enjoy — though we must still try to keep as safe as possible. CNN: When will your children see their grandparents? Wen: We are planning summer or early fall of 2021 to have my father visit us from Vancouver, Canada. My husband’s mother is in Johannesburg, South Africa. We hope to visit her for Christmas 2021, if everyone is vaccinated by December. They haven’t seen my 3-year-old for more than a year, and it will be their first time to meet the baby — who is now 9 months old. We can’t wait —though we will be patient and keep safe in the meantime!