What experts say about the World Cup heat so far

With the World Cup already in full swing, many doctors warn that the risks of extreme heat go far beyond actions on the field - especially in certain venues, and could affect millions of fans and thousands of workers.

Summer always brings heat, but the places that pose the greatest risk can surprise you. In the United States, experts are keeping an eye on stadiums in three host cities: Miami, Kansas City and Philadelphia.

Some U.S. host cities with warmer climates - Atlanta, Houston and Dallas - have indoor, air-conditioned stadiums, which can offer some protection to fans and workers. But Miami, Kansas City and Philadelphia are home to open-air stadiums, which means they have the potential to expose fans to "very intense heat" and "very high humidity," said Dr. Fabian Arous, a sports medicine physician at Children's Health Andrews Institute for Orthopedics and Sports Medicine and holder of a FIFA diploma in football medicine.

Regardless of where they are, experts warn that fans should be aware of the heat during outdoor events, including before and after matches.

"There are two things we worry about: heat exhaustion and, more seriously, heatstroke," Arous said.

"I would raise all my red flags for the city of Miami as my biggest cause for concern," said Dr. Douglas Casa, University of Connecticut Board of Trustees Distinguished Professor and executive director of the Korey Stringer Institute, where he studies the impacts of heat and hydration on athletes, military personnel and workers.

Casa added that spectators and workers are at a greater risk of heat-related illnesses than the athletes themselves.

Players have access to medical teams, cooling breaks, elite training and carefully monitored conditions, but many of the people who make the World Cup possible - including spectators, security guards, food stall staff and construction workers - can spend hours in the heat without getting the same relief, especially in open-air stadiums.

The last FIFA Men's World Cup, held in Qatar in 2022, was marred by controversy, with reports that migrant workers were working in hot and humid conditions that put their lives at risk in the run-up to the tournament.

Kansas City Stadium is one of the outdoor venues that will host World Cup games, which could pose heat risks for fans in attendance, experts warn. - Sebastian Widmann/FIFA/Getty Images via CNN Newsource
The event was held in November and December, and seven of the eight stadiums were covered and temperature controlled.

But this summer in the United States, Canada and Mexico, most World Cup matches will be held in outdoor stadiums.

"This could be the hottest World Cup in history," said Casa.

Preparing for heat risks
As part of this year's World Cup schedule, Miami hosts seven matches, while Kansas City and Philadelphia have six each.

When Ivory Coast defeated Ecuador 1-0 in Philadelphia on Sunday, there was a slight increase in heat-related complaints among fans treated at the stadium's medical facilities, and "temperatures were well above 90," said Dr. Kathleen Faccio, an emergency physician at Jefferson Abington Hospital. She also works in event medicine and collaborates with the FIFA medical team at the World Cup matches in Philadelphia.

"Most people had some mild heat-related illness, mild heat exhaustion," she said. There are two medical areas in the stadium with doctors on duty and accessible to fans. Faccio's colleagues worked at the facility on Sunday, and she is scheduled to work there during Monday's match.

"Thermal exhaustion specifically, which is the most common presentation we see, can manifest a range of symptoms that include headache, nausea, fatigue, abdominal cramps and leg cramps," Faccio said, adding that she and her colleagues are preparing for upcoming matches and will ensure there are intravenous fluids among the medical supplies available on site.

Philadelphia Stadium has two on-site medical areas for fans and employees, including those who may be experiencing heat-related symptoms. - Joe Prior/Visionhaus/Getty Images via CNN Newsource
"There will be a lot of excitement, and a lot of families maybe tailgating in the parking lots," she said. "I really anticipate that even before the game starts, we'll already have some patients."

At Miami Stadium, Jackson Health System worked with FIFA to set up medical areas for spectators who may need care, said Dr. Hany Atallah, chief medical officer at Jackson Memorial Hospital.

"Heat is certainly on our list of concerns," said Atallah.

"We're making sure we have adequate supplies available. If someone needs IV fluids or other care, that we have those things available," he said.

"At the same time, we obviously have the support of our emergency medical service colleagues and we have a transportation plan in place to get people to a hospital if their medical condition requires that transfer."

During the World Cup match in Miami on Monday, which ended in a draw between Uruguay and Saudi Arabia, the heat index exceeded 100 degrees Fahrenheit, said Dr. Jose Llach, regional medical director of urgent care centers at Baptist Health South Florida.

"It's going to get even hotter here in Miami because July is a hotter month compared to June," he said, adding that he expects heat-related risks to increase as the World Cup progresses. "Some games are more competitive as the tournament progresses, so what happens is there will be more fans in the stadiums, creating a hotter environment, making it more dangerous for the community and the fan base."

Those watching World Cup matches are not the only ones at risk from the extreme heat. Game viewing parties and FIFA-sponsored Fan Festivals are being held in cities across the country.

Evan Young was among the fans who were already feeling the rising temperatures at these events. It was a hot summer night in Decatur, Georgia, where he spent hours in the heat before the start of the match between the USA and Paraguay, scheduled for 9pm on Friday.

"We got here around 6 p.m.," Young, 31, said at WatchFest in Decatur, outside Atlanta. "It's very hot. I think it was 92 degrees when we left the house."

He visited the WatchFest event's cooling station, equipped with water mist fans, at least four times that night.

Recognizing the signs
Host cities across the United States are monitoring forecasts to determine when high temperatures could pose public health threats this summer, said Lori Tremmel Freeman, executive director of the National Association of County and City Health Officials.

For example, Houston is anticipating heat indices approaching 105 degrees Fahrenheit during the tournament, she said.

Extreme heat remains the leading cause of weather-related death in the United States.

"It is sometimes overlooked as an active area of public health surveillance, but extreme heat and the effect it has on people during these events is squarely within the purview of our local health departments, and they are looking at what risks may be posed by the heat as well as air quality," Freeman said.

And while teams monitor the health of their players, public health departments monitor the health of communities.

"So the role of public health would be to ensure that there are adequate tents and cooling facilities and appropriate emergency partnerships in place that can both serve people who may be affected by the heat and ensure that they are prevented from being affected by the heat," Freeman said.

There is a spectrum of heat-related illnesses that can have varying effects, said Dr. Jonathan Bar, an emergency physician and director of emergency preparedness at Penn Medicine in Philadelphia.

"In milder forms, you may get heat rash. This occurs when sweat clogs the skin's pores, and disappears with cooling and gentle exfoliation," said Bar.

"Heat cramps are a level above where it's usually due to electrolyte issues, and so staying hydrated is really important for that," he said. "You can get heat edema - moving up the spectrum - which is when your legs can swell a little, and this usually goes away when you go to a cooler area with compression."

Bar added that "heat exhaustion and heat stroke are on the more serious end" of the spectrum. Symptoms of heat exhaustion may include headache, nausea, dizziness, heavy sweating, and elevated body temperature.

"What really differentiates heat exhaustion from heat stroke is the involvement of the central nervous system," said Bar, as symptoms of heat stroke include confusion, loss of consciousness or seizures.

"It is important to recognize them quickly, because these are life-threatening medical emergencies."

According to the Mayo Clinic, treatment options for heat exhaustion and heat stroke include quickly reducing body temperature by cooling the skin with immersion in cold water or ice.

Casa, who survived a heatstroke in 1985, emphasized that "the best treatment is immersion in cold water."

How to prepare and what to bring

Whether you're attending a World Cup match or a viewing party, there are items you can bring to reduce your risk of heat-related illness. And, of course, it's important to check whether the stadium or venue has specific scholarship requirements.

Miami is considered the hottest city among outdoor World Cup venues this summer, on average. - Leonardo Fernandez/FIFA/Getty Images via CNN Newsource
Water bottle
After facing pressure from the media and the football community, FIFA changed its policy to ban ticket holders from bringing some types of water bottles into stadiums. Fans in the US and Canada are now permitted to bring "one disposable, soft, plastic, 20oz (590ml), factory-sealed water bottle to any FIFA World Cup 2026 match." But "fans will not be allowed to bring reusable water bottles for safety reasons."

Anyone going to a World Cup match should bring one bottle of water per person and "drink that water when they enter and then use the refill points or bathrooms to replenish the water," Casa said.

Sun protection
Remember to not only bring sunscreen, but to apply it generously and often. It is recommended to apply sunscreen at least 20 minutes before sun exposure. Then reapply at least every two hours.

"Preventing sunburn with sunscreen is really important," said Bar.

Hats, sunglasses, and loose-fitting clothing with SPF can also help reduce sun exposure and keep you cool.

Consider bringing a wide-brimmed hat to cover your head, neck and face, Casa said.

During the opening match of the World Cup last week, some Mexico fans were seen throwing sombreros into the air in celebration as their team defeated the Republic of South Africa 2-0, but the hats could come in handy for the rest of the tournament.

Fans and towels
There are dozens of cooling products that football lovers can use to stay cool, such as portable fans and hand towels that can be moistened with water.

If you dip a small hand towel in cold water, use it to cool off, Llach said.

"Just wet it with some water in the bathroom and put it around your neck while you watch the game, and it makes a big difference," he said, adding that it can help reduce the risk of heat-related emergencies.

Beware of Medications
Older adults are recommended to carry any medications they normally take at the time the game is taking place, Faccio said.

"There are a lot of World Cup fans over the age of 65, and sometimes we forget that medication timing is really important for this specific population. If you get to the game at 4 or 5 o'clock and you can't leave, when you finally get home around 11 or 12, you're going to be without that antihypertensive medication or that Parkinson's medication," she said. "That can be really harmful."

Additionally, Bar warned that certain medications and heat can interact, potentially increasing the risk of heat-related illnesses. These medications may include antihistamines, beta blockers, diuretics, antipsychotics, and stimulants such as ADHD medications or SSRIs.

It is important to talk to your doctor if you are going to spend an extended period of time outdoors while taking any medication that may interact with heat.

Extreme heat: understand how high temperatures affect the body and health

Source: CNN