NYC is already a global city, and now it’s about to become a global party.

Starting this week, soccer fans from around the world will pour into New York and New Jersey for the 2026 FIFA World Cup. MetLife Stadium will host eight matches, including the final, and New York City will be the airport, hotel room, dinner table, subway transfer, fan zone, and late-night celebration setting for a whole lot of people.

I’ll admit, when I first started thinking about the World Cup and health risks, my mind immediately went to infectious diseases. A million people coming into NYC from around the world? Packed trains? Fan zones? Of course, my mind was on disease transmission.

But the more I learned from Dr. Syra Madad, Chief Biopreparedness Officer at NYC Health and + Hospitals and one of the people in New York whose job is to think about the “what ifs,” the more my frame of reference shifted. At NYC Health + Hospitals, she helps lead systemwide preparedness, mitigation, response, and recovery efforts across the country’s largest municipal health care system.

She helped me see that the biggest World Cup health challenges may not be the Hollywood-style outbreak scenarios. That the ordinary city risks, like extreme heat, foodborne illnesses, crowded emergency departments, are dialed up a notch for the next six weeks and may be the bigger concern.

So today, I’m diving into what it takes to sustain a prepared health system during a global event like the World Cup. Here’s what I learned.

Probability X Consequence

Preparedness sits at the intersection of probability and consequence. For example, extreme heat is likely, while an emerging infectious disease outbreak is less likely but potentially more disruptive.

For World Cup planning, this means holding both truths. Preparing is about building a flexible system that can handle the expected, detect the unusual, and absorb the added health burden without falling apart.

Here’s what NYC is getting ready for

First: heat and routine health strain. Likelihood: High. Consequence: Moderate to high depending on severity and system strain.

Heat is the one that keeps coming up because the World Cup will happen in June and July, and heat is already one of New York City’s most serious weather-related health threats. NYC estimates that more than 500 New Yorkers die prematurely each year because of hot weather, and emergency department visits spike. When it’s 90 degrees out, you might get 20-ish heat related ED visits in NYC in a day—not very many. When it increases to 100, you could see ~150—a rapid jump that EDs may or may not be ready for.

Heat is not just uncomfortable. It can worsen heart and lung disease, cause dehydration and heat stroke, and put older adults, outdoor workers, people without reliable air conditioning, young children, pregnant people, and people with chronic illnesses at higher risk.

Add packed trains, outdoor watch parties, alcohol use, long lines, and crowded emergency departments, and the risk rises quickly.

Then there are other, less dramatic issues that become a problem at scale. Things like food safety, alcohol-related injuries, substance use, sexually transmitted infections (STIs), mental health crises, and crowded emergency departments.

None of these is unique to the World Cup. They are normal city health issues, but dialed up with one million extra visitors.

Second: infectious diseases. Likelihood: Low to moderate, depending on the pathogen. Consequence: Low to very high, depending on transmissibility, severity, and speed of detection.

Infectious diseases still matter. A global event means people arrive from many places, move through crowded spaces, eat together, cheer together, and then disperse again. That does increase the opportunity for transmission.

But it doesn’t mean we should expect some scary outbreak. It means public health teams will be watching the basics: respiratory viruses, measles, foodborne illnesses, norovirus, and anything unusual that shows up in emergency department data or lab reporting. Several groups, including Biobot (where I work during my day job), Verily, WastewaterScan, SecureBio, and other academic and public health groups are also using wastewater as an early warning system for pathogens.

For New York, measles is probably the one top of mind. The state has already seen 12 cases in 2026, with 6 of those in NYC. Most, if not all of these, are from someone either visiting from another country, or a resident who caught it while traveling abroad and brought it back. None of those cases resulted in additional transmission, meaning we haven’t seen any outbreaks in New York this year. But it only takes one case in a pocket with low vaccination rates for measles to spark an outbreak. And this could have big consequences. Not only is measles dangerous, but it creates a lot of follow-up work: exposure notifications, contact tracing, vaccination checks, infection control, and public messaging.

Many have also asked about Ebola or Andes virus outbreaks during the World Cup. While those could have high consequences, the probability of them occurring is very low.

Third: Violence or mass casualty. Likelihood: Low. Consequence: Very high.

This is the category everyone hopes never materializes, but no emergency planner can ignore.

Large-scale violence, terrorism, a crowd stampede, or another mass casualty incident is lower probability than heat-related illness or alcohol-related injuries. But the consequence could be catastrophic, especially in a dense city with crowded transit, fan zones, hotels, bars, and public viewing areas.

For the World Cup, this is also a coordination challenge. Hospitals, EMS, law enforcement, emergency management, transit agencies, venues, community organizations, and communications teams all need to know their roles before something happens. Recent reporting notes that the 2026 World Cup has been assigned a high federal security designation, requiring coordination across federal, state, and local agencies.

What preparedness actually looks like in NY

New York City knows how to host a crowd. Times Square alone draws an estimated 1 million people on New Year’s Eve and the city regularly manages parades, concerts, protests, marathons, and major holidays. But the World Cup is different because it is not one night or one event. It is a prolonged, citywide event unfolding over six weeks, alongside other seasonal events like Fourth of July, Sail4th 250, summer tourism, concerts, parades, and so much more.

That is the kind of planning the Office of Biopreparedness and Emergency Management has been doing for more than a year: not preparing for one scenario, but ensuring the health system can remain steady amid shifting conditions and compounding threats. That includes clinical and operational working groups, lessons from past World Cups and mass gatherings, local weather and disease trend monitoring, and exercises focused on patient surge, heat illness, alcohol intoxication, injuries, power disruptions, norovirus, measles exposure at a fan event and other low-probability but high-consequence scenarios.

For infectious diseases in particular, the team is looking across five practical categories: vaccine-preventable diseases, respiratory viruses, arboviruses, high-consequence pathogens, and gastrointestinal illnesses. For operations, the focus is just as much on the fundamentals: situational awareness, incident command, clear communication, fast information-sharing, worker safety, staffing, supplies, isolation pathways, and keeping emergency departments and hospitals functioning even when demand shifts.

The goal is not to make the World Cup feel scary. It is the opposite. Good preparedness is what empowers a city to enjoy a global moment with confidence. If the system works well, most people will never see it. They will just see New York doing what New York does: welcoming the world, absorbing the surge, and keeping the city moving.

Communication plays a huge role

Communication is a crucial part of the response. During a major event, people do not just need information. They need information they can understand and narration from sources they already trust, before rumors fill the gap.

That’s why YLE New York and NYC Health + Hospitals are participating in the Health System Operations Center, or HSOC, the first non-governmental health intelligence center weaving all data sources together across states to provide a bird’s-eye, national view of the health issues surrounding the World Cup. As part of this, we’re helping to coordinate and share timely, accurate information across partners and the public.

Hospitals, EMS, emergency management, public health departments, law enforcement, transportation agencies, community organizations, hotels, venues, and trusted messengers all have different jobs. But for an event like this, those jobs have to connect. A hospital cannot prepare in isolation. A public health alert is only useful if clinicians see it and know what to do. A heat warning only helps if people know where to cool down and how to recognize danger signs. A communication plan only works if it reaches people in the language and format they actually use.

And making sure the right people have the right messaging and communication chains is critical for preparing for major events.

Here’s what New Yorkers can do:

Most of us do not need to do anything dramatic. But there are a few practical things that can help:

• Know your heat plan. If your home gets too hot, know where you can cool down: a friend’s place, a library, a cooling center, or another air-conditioned space. Find NYC cooling centers here.
• Stay home if you’re sick when you can, and consider masking in crowded indoor spaces if respiratory viruses start circulating or you’re around someone high-risk.
• If you’re going to matches, watch parties, or crowded events, hydrate, wear sunscreen, pace alcohol, and have a plan for getting home.
• Keep medications with you if you’re traveling around the city, especially if you rely on them daily (there could be transportation delays).
• For healthcare practitioners, the NYC Health Department has put together an information page with recommended clinical guidelines and other resources on public health concerns that may impact New Yorkers and visitors during summer events like the World Cup.
• Maybe most importantly: pay attention to official updates. Preparedness exists so the public does not have to wonder or carry anxiety alone.

And, if you live within 30 miles of a World Cup game (NYC and North New Jersey, that’s you!), you can participate in our weekly World Cup Pulse Survey. It’s a few questions each week about what health topics are on your mind, what rumors or concerns you’re hearing, and what questions aren’t getting answered. Sign up here. 🙂

Bottom line

The World Cup is going to bring noise, crowds, flags, chants, packed trains, impossible restaurant reservations, and the kind of energy New York is known for. Preparedness is not about draining the joy out of that, but protecting it.

When the infrastructure is strong, the city can do what it does best—welcome the world, take care of its people, and celebrate.

Love,

Your NY Epi

Dr. Marisa Donnelly, PhD, is an epidemiologist, science communicator, and public health expert. This newsletter exists to translate complex public health data into actionable insights, empowering New Yorkers to make informed and evidence-based health decisions.