The effects are greater when the Super Bowl occurs close to the peak of flu season or when the dominant influenza strain is more lethal, researchers said.
Researchers looked at county-level statistics in US from 1974-2009. They found having a team in the Super Bowl resulted in an average 18 per cent increase in flu deaths among those over 65 years old.
The Super Bowl is the annual championship game of the National Football League (NFL), the highest level of professional football in the US.
"It is people that are staying at home and hosting small local gatherings, so your Super Bowl party, that are actually passing influenza among themselves," said lead author Charles Stoecker, from Tulane University in US.
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"Every year, we host these parties that we go to and it changes mixing patterns and you are coughing and sneezing and sharing chips and dip with people that you often do not and so we get the influenza transmitted in novel ways that is then going to eventually wind up in the lungs of a 65-year old," he said.
The findings were published in the American Journal of Health Economics.