WARNING: Having your home team in the Super Bowl may be hazardous to your health

Sorry, football fans, but having your hometown team make it to the Super Bowl might not be such a good thing after all. In fact, it might make you sick.

A new study in the American Journal of Health Economics finds that the number of people older than 65 who die from influenza (also known as the flu) goes up an average of 18% when a city sends a team to the big game compared with years when the same team doesn’t make the cut.

The researchers conclude that all those celebratory Super Bowl parties, high-fiving, and dip sharing in the finalists’ hometowns provide an easy way for flu to spread.

“The basic thing is you get people together and they cough and sneeze on each other,” said Charles Stoecker, a health economist at the University of Tulane who lead the study. “And small local gatherings are likely to be more popular in a city that has a team in the Super Bowl.”

Previous studies had shown an increase in influenza infection rates at big sports gatherings like the 2002 Winter Olympics and the 2006 World Cup. However, Stoecker and his coauthors discovered no significant increase in the number of people who died from flu in cities that hosted the Super Bowl over the last 30 years.

The researchers propose two possible reasons for that finding. They note that the majority of Super Bowls are held in Southern states where the weather is warmer and less hospitable to flu transmission. In addition, football fans who come into town solely for the game may not mix with the local population, which would keep them from transmitting the flu they might have brought with them or picked up while traveling.

In cities that sent teams to the game, Stoecker and his team report that the “Super Bowl effect” was compounded in years when the dominant flu strain was more virulent or when the Super Bowl was held within 24 days of the peak of the flu season.

“This assured us we were picking up something real instead of just an artifact of the data,” Stoecker said.

But before you cancel your Sunday Super Bowl plans, know that you can watch the game with friends and avoid the flu.

“Get vaccinated, wash your hands, cover your mouth when you cough and stay home if you are sick,” Stoecker said. “Knowing that people gathering together transmits influenza is not something new. During influenza season you have to be mindful and protect yourself.”

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