Editor's Note — There are few no-risk activities during the Covid-19 pandemic, but there are ways to reduce risks. Fully vaccinated people are, of course, at much lower risk of contracting and spreading coronavirus than unvaccinated people. CNN Medical Analyst Dr. Leana Wen advises approaching your decisions with that in mind. This story has been updated to reflect the US Centers for Disease Control and Prevention's new guidance on mask-wearing issued May 13.
(CNN) — If you're wondering whether an amusement park is a safe place to have fun after more than a year of pandemic struggles, know that the answer isn't black-and-white.
And the safety measures in place at US amusement parks are evolving and may vary based on the state where the park is located. Disneyland in California and Disney World in Florida, for example, have different rules for their guests.
Coronavirus spreads through exposure to respiratory droplets carrying the virus, virus accumulated in or flowing through the air or, to a lesser extent, surfaces contaminated with the virus. Because of that, the risk levels of amusement parks depend on the safety precautions they take to reduce Covid-19 transmission, according to the US Centers for Disease Control and Prevention's guidance for traveling amusement parks and carnivals.
Employees sanitize roller coaster seats at Six Flags Magic Mountain in Valencia, California, on April 2 -- the second day that the park reopened after more than a year of being closed because of the pandemic.
Mel Melcon/Los Angeles Times/Getty Images
That can apply to permanent amusement parks, too, said CNN Medical Analyst Dr. Leana Wen, an emergency physician and visiting professor of health policy and management at the George Washington University Milken Institute School of Public Health.
"If the amusement park is entirely outdoors and you're going at a time when it's not a bunch of people packed into a very small space, if you can keep some pretty good physical distancing, and if masks are required, I would feel pretty good about going," Wen said. "That changes if any of those factors are not there.
"If it's outdoors, there's going to be very good air circulation. We now know that surfaces are not the major issue."
Fully vaccinated people don't need to wear masks nor physically distance unless they're on public transportation or required to by local laws or businesses, the CDC announced May 13. Fully vaccinated people who are immunocompromised -- or living with immunocompromised people -- should still be careful, since immune-weakening conditions make someone at higher risk for serious disease and death if they contract coronavirus.
Risks for unvaccinated people
Unvaccinated children and adults are still at high risk for Covid-19, Wen said.
"Indoor, crowded settings should be avoided, especially if there are others around them who are unvaccinated and not wearing masks. Outdoors, the risk is much lower," she said. "If amusement parks are really important to the family, they could consider going but try to stay distanced from other individuals and limit their time in indoor settings. Try to stay outdoors as much as possible."
This weekend, Disney welcomes guests to Avengers Campus, a new themed land inside Disney California Adventure park at Disneyland Resort in Anaheim, California. Until June 15, only California residents may visit Disneyland theme parks in groups no larger than three households.
Right now, Disneyland is requiring that guests and cast members ages 2 and older -- including vaccinated people -- wear face masks at all times, except when eating, drinking or swimming. But rules could change starting June 15, when California is expected to fully reopen, dropping capacity and distancing restrictions for most activities and businesses in the state. At Disney World in Florida, however, things are a bit different: Disney World's rules say mask-wearing is optional in "outdoor common areas" and on pool decks. Mask-wearing is still required in entrances, throughout all attractions (including in lines), in all indoor spaces and on transportation.
Before you go to an amusement park
By calling or looking online, check whether the park has been complying with CDC guidelines for traveling amusement parks -- or with similar precautions regarding cleaning frequently touched surfaces as much as possible, physical distancing and mask-wearing. If you don't live in the same state or country as the amusement park, call the park or check its website to know whether the park is allowing out-of-state visitors. You may need to make reservations since some parks may be limiting capacity. Look for advance ticketing options so that you and your group can enter the park using contactless check-in.
Also, look at online review forums and navigation apps to see what the experiences of recent guests have been, Wen suggested. "Does it seem like masking is enforced? Also, what are the most crowded times, and what does it look like when it's crowded? Are you able to maintain physical distancing? If not, you may want to reconsider the trip."
If you do go to an amusement park with unvaccinated children, set their expectations for what the trip may be like.
"Discuss with the family, in advance, about what to do, including if you show up and it's too crowded and you may need to leave," Wen said. "Kids may otherwise be very disappointed if that were to occur."
And the vaccination rates of states can make a big difference in terms of safety or risk level, said Dr. Ada Stewart, a family physician with Cooperative Health in Columbia, South Carolina, and the president of the American Academy of Family Physicians.
Nearly 80% of Vermont's vaccine-eligible population has received at least one dose of a Covid-19 vaccine, for example, whereas 45% of South Carolinians have received at least one shot.
While you're at the park
While there have been few documented cases of surface transmission of coronavirus, "there are also other pathogens that can be transmitted through high-touch surfaces," Wen said.
"Make sure to bring hand sanitizer and, if you see your child touching surfaces that others have also likely recently touched, squirt some hand sanitizer on your kid and use it throughout your visit." Adults, too, should use sanitizer before and after they touch things such as ATMs, handrails or food.
"We don't know how frequently they're wiping down those rides," so bring sanitizing wipes as well, Stewart said.
When you're on rides, "a lot of times you're screaming," said Regina Davis Moss, the associate executive director of health policy and practice at the American Public Health Association. "These are also potential opportunities for droplet spread."
Choose rides that allow for enough space between groups from different households -- and remember to keep your mask on if you're unvaccinated or if the park requires mask-wearing regardless of vaccination status.
Carry more than one mask in case one gets wet, which can make it less effective and complicate breathing. For unvaccinated people, bringing your own food and eating at least 6 feet away from people who don't live in your household -- or finding a restaurant with outdoor seating -- is safest. Many businesses have closed public water fountains, so you may need to bring along a water bottle as well.
Avoid touching shared items, such as gaming equipment, if you haven't seen park staff clean it between guests. If you're unvaccinated and play arcade games, make sure that only your group is at the booth.
Overall, unvaccinated people will need to pay closer attention to social distancing and other measures to avoid Covid-19 infection.