As summer winds down, the highly transmissible delta variant of SARS-CoV-2, which is now dominant in the U.S., is prompting questions about everything from when it will be safe to return to work to how to keep children safe in schools.
For many people, summer travel plans are also in limbo.
On Tuesday, the Centers for Disease Control and Prevention changed its guidelines for fully vaccinated people, advising that they wear masks indoors in places where there are high or substantial rates of transmission. The counties that meet that criteria make up about two-thirds of the U.S. population, according to a CNBC analysis of the agency's data.
"We are dealing with a different virus now," Dr. Anthony Fauci, White House chief medical advisor, said about the delta variant in an interview with NPR on Tuesday.
So is it even safe to travel? The answer completely depends upon your own individual circumstances, including your risk profile and tolerance, Dr. Ashley Lipps, assistant professor in the division of infectious diseases at The Ohio State University Wexner Medical Center, tells CNBC Make It.
Here are some questions you might have approaching summer travel plans:
No travel is completely safe, and how safe it is depends on individual circumstances.
But the best thing to do if you're planning to travel is to make sure that every person in your travel party who is eligible is fully vaccinated, including all adults, Lipps says. The CDC recommends that you delay travel until you are fully vaccinated.
Rules for unvaccinated people who need to travel are stringent: The CDC says unvaccinated people should get tested one to three days before traveling and again three to five days after returning, plus quarantine for seven days upon returning home.
Both vaccinated and unvaccinated people have to wear masks on planes, buses, trains and other forms of public transportation, as well as inside transportation hubs such as airports and stations.
Everyone should self-monitor for Covid symptoms.
Travel is tricky for families with young children, because vaccines are not yet available for children under 12. "If your kids are old enough to be able to wear masks on a plane, that certainly would help reduce the risk a little bit," Lipps says.
You can also take steps to minimize your exposure to other people, such as driving in car versus flying on a plane and stick to outdoor activities at your destination, she suggests.
But Kullar says it's best for families with young children to "wait until this surge has come to a plateau" to travel.
Planes are inherently a little bit riskier, because you're inside and close to many other people whose vaccination status you may not know. Make sure that you're fully vaccinated before getting on an airplane.
Because delta is more transmissible than other variants, "there's a higher probability, especially in those airport settings which are indoors, of putting you at risk and potentially, transmitting it and spreading it," Kullar says.
Everyone wearing masks, which is required on public transportation by federal rules, can reduce the risk of transmission, Lipps says. "Taking the precautions outlined can certainly reduce your chance [of infection]," she says.
Kullar says that while masking is mandate and typically enforced by flight attendants while aboard the plane, you should also be careful while at the airport, where it's more crowded and mask-wearing may not be closely monitored by staff.
"The airport is probably the riskiest," Kullar says.
According to the CDC, short road trips with members of your household or fully vaccinated people with only a few stops along the way is a safer choice.
The bottom line is that no destination is zero-risk.
"Covid is just widespread everywhere, so there's going to be some risk regardless of if you're in a high transmission area versus a lower transmission area," Lipps says.
Knowing the transmission rate at your destination is just one factor that can help you consider the overall risk for your trip, Lipps says. For example, if you're going to a state that the CDC has classified as high or substantial transmission, you'll need to wear masks in public indoor settings whether you're vaccinated or not. Some places now have mask mandates.
The CDC has a map that shows you the level of community transmission by county. You can also check the state or local health department's website for specific information about your destination.
Also be mindful of the people you're traveling with and how their individual risk factors play into your decision, Lipps says.
"If you're planning on going somewhere where there's very high rates of transmission and you have either unvaccinated children or adults who may be immunocompromised or otherwise for high risk, it may be helpful to avoid that kind of travel or travel somewhere where there's maybe less community transmission," she says.
The CDC suggests that you refer to its travel recommendations by destination before traveling internationally.
Certain countries don't have as much access to Covid vaccines, "so you may be traveling to places where there's far less people vaccinated than here in the United States," Lipps says.
And "in most places other than the U.S., delta is just as much of a concern, if not more in some of the Asian countries," Kullar says. "I would put a hold on international travel until we're out of the thick of this."
Additionally rules and regulations are shifting as situations change around the world.
On Wednesday, the U.K. announced that travelers from the U.S. and E.U. no longer have to quarantine upon arrival to England or Scotland. And Canada will allow fully-vaccinated Americans to enter the country starting Aug. 9 for the first time since March 2020.
"You have to be careful if you're planning international trips because there may be changing travel restrictions coming up that we just can't predict at this point," Lipps says.
Testing requirements, stay-at-home orders and quarantine requirements also vary from place to place.
Take the Caribbean Islands, for example: Bermuda requires that unvaccinated visitors quarantine for 14 days upon arrival. Vaccinated people also have to quarantine in Bermuda until they receive a negative PCR test. But in the Bahamas, fully vaccinated people don't have to get tested or quarantine for entry.
Another thing to keep in mind if you leave the country: The CDC requires any passengers coming to the U.S. to have a negative Covid test result (or documentation showing you've recovered from Covid) before they board a flight to the U.S.