CHICAGO, Ill. — Canceled last year, Lollapalooza made its return this week. The annual four-day music festival is expected to draw 100,000 people. It’s one of the first giant events in the country since the pandemic began. More are planned in the coming months including Bonaroo, the Governor’s Ball, and Summerfest.

Despite health checks, some in public health are watching this event closely, concerned a head-on collision with the delta variant could turn the outdoor concert event into a super spreader event.

Still, following months of isolation, tens of thousands have flocked to Chicago’s Grant Park to escape the pandemic and enjoy outdoor music.

“It's my second time out at Lollapalooza,” said Kevin Metras, a Lollapalooza attendee. “I'm so excited. It's nice, hot. You know, I'm trying to sweat and stay hydrated.”

It’s the first major music festival in the U.S. since the outbreak began. But it comes at a time when COVID-19 cases are surging in parts of the country.

“You know, I got my vaccine, I'm young, I'm healthy, I think I should be OK,” said Ishi Nagpal, a Lollapalooza attendee who chose not to mask.

Yet, guidelines to attend Lolla were recently loosened.

At first, proof of full vaccination or a negative COVID-19 test 24 hours before entering each day was required. That was downgraded to within 72 hours of arrival.

“No, we're all going to die either way,” said Lollapalooza attendee Kailee Parker

Masks are mandated for all unvaccinated attendees, but it’s unclear how that’s going to be enforced once you get past the gates.

“Yeah. You know, probably when I’m within the groups of people I probably might wear it a little bit,” said Metras, who is wearing a mask. “It just makes us all feel good. I'm vaccinated but, you know, gotta take that extra step sometimes.”

“The Lollapalooza organizers haven't really made good on their promise to use electronic apps to track vaccination and testing. And so far, ticket holders haven't had to upload those things,” said Dr. Emily Landon, an infectious disease specialist at the University of Chicago Medicine.

A busy Fourth of July weekend resulted in a cluster of COVID-19 cases in Provincetown, Massachusetts. There were more than 830 cases. About 74% of them were reportedly breakthrough infections among vaccinated visitors who became symptomatic.

“I can't promise that there won't be any COVID cases associated with Lolla when you're having this many folks who are coming through,” said Dr. Allison Arwady, commissioner of the Chicago Department of Public Health. “Almost certainly there will be some cases.”

City public health officials admit there are risks of COVID-19 spreading even outdoors at massive gatherings like Lollapalooza, but remained confident that they’ve taken proper precautions.

“I'm certainly hopeful that we won't see a significant problem. And I certainly know we're being a lot more responsible than many other settings,” said Arwady.

But unlike barriers and fencing, what happens on these grounds can’t be contained.

“The one thing that will make Lollapalooza into a really dangerous event for the rest of this country will be if people leave Lollapalooza, go back to their unvaccinated communities and ignore the symptoms that they have afterward,” said Landon.

Some infectious disease experts recommend getting tested after attending massive outdoor festivals, especially if you experience any symptoms.

“We're planning on getting tested a few days after just in case, you know, you can never be too careful,” said Cassie Cabanas, a Lollapalooza attendee who is wearing a mask even though she is vaccinated.

But some experts say there’s only one real way to side-step the threat.

“If you don't want to get COVID, don't go to Lollapalooza,” said Landon.

Experts say contact tracing across state lines will be key in assessing the ripple effect of mass gatherings like Lollapalooza. The results could also set the stage for health protocols at other major festivals.

CHICAGO — Thousands of fully vaccinated people have contracted the coronavirus, but experts say these breakthrough cases are rare.

“The total number of individuals who are vaccine breakthroughs is pretty low compared to the number of cases that are out there,” said Dr. Emily Landon, an infectious disease specialist at the University of Chicago Medicine.

But according to Dr. Landon, that risk can easily go up and have far-reaching impacts beyond the person infected.

“The more contact and close contact you have with people who are unvaccinated, the more likely you are to have a breakthrough infection,” said Landon.

As of July 19^, the CDC documented nearly 6,000 cases of fully vaccinated people who were hospitalized or died from COVID-19, and 74% of them were 65 or older.

But the agency acknowledges those numbers are under-counted.

In Massachusetts, for example, where 63% of the residents are fully vaccinated, 5,000 breakthrough cases have been reported with 80 deaths.

“Every time someone gets COVID, whether they're vaccinated or not, it gives the virus an opportunity to spread to someone else or to mutate inside their body,” said Dr. Landon.

It’s why vaccination rates matter.

More than 160 million people in the U.S. have already been fully vaccinated, but that’s less than 50% of the total population.

“The more people that are vaccinated, the fewer cases of COVID we're going to see in general and the fewer variants we're going to see emerge,” said Dr. Landon.

And with the more contagious delta variant twice as transmissible, experts warn the more the virus can circulate among the unvaccinated, the more likely the chance of breakthrough cases and potentially vaccine-resistant mutations, which could lead to more spread.

“Any individual who is symptomatic, whether they've been vaccinated or not, should consider themselves to be contagious.”

In the end, experts like Dr. Landon say vaccination is key. But being fully vaccinated doesn’t mean someone is fully protected.

“For people who aren't willing to follow the science, it turns out it might be better for all of us to just wear a mask so that we know that everybody's protected," Dr. Landon said.

Nearly 1 in 5 adults in the U.S. live with mental illness, and there are a number of ways to seek treatment -- from psychiatrists, who have the ability to prescribe medication, to psychologists, therapists, and counselors.  

"There's a varying spectrum of ways that you can approach dealing with things like anxiety, depression, substance use disorders," explained Dr. Eric French, Medical Director of Adult Psychiatry at the Medical Center of Aurora. "Sometimes that involves medications if it's warranted. Some people are able to get by with just some therapy. There's cognitive behavioral therapy. There’s dialectical behavioral therapy, there’s motivational therapy, interpersonal, there are so many different types. And the reason that's encouraging for our patients out there is is that we will tailor-fit what you need to you."

Dr. Flavia DeSouza a Board-Certified Psychiatrist and Assistant Professor at Howard University explained that psychotherapy can do any number of things, including helping us regulate our emotions.

"Particular skills that are taught, it may help us to slow down our thoughts to understand what is actually going on in our minds, and how it is affecting our behavior and our feelings," Dr. DeSouza said. "It may help us to name our feelings. Many of us just go through life, without actually knowing what's going on inside of us. It may help us to learn how to change our behavior, or thinking or feeling — so that we can function in a healthier way."

Regardless of the method you start with, remember that it may take time to find the right fit or the right mental health professional. 

"You don't have to stick with this, the first therapist that you find, sometimes there's not that match," said Nii Addy, a Neuroscientist, and Host of the Yale University Podcast, Addy Hour. "So there's no there's no shame in saying, Okay, this person is not quite working for me, I'm gonna move on to the next."

A good place to start that search is findtreatment.gov or to learn more about the various types of treatment, check out the National Alliance on Mental Illness at nami.org.

Amber Strong at Newsy first reported this.