LOS ANGELES (KABC) -- There have been nearly 9,000 confirmed flu-related hospitalizations, which is almost double the number at this point last year, according to the Centers for Disease Control.A study, which appeared in the "New England Journal of Medicine," said that people are six times more likely to get a heart attack after contracting the flu virus."Theories as to why that happens? It actually makes sense in terms of the physiology. There is inflammation when we have an upper-respiratory viral infection. That triggers an increased clotting risk. And then there's oxygen demand and supply mismatch that can affect the heart," said Jen Ashton, ABC News Chief Medical Correspondent.The flu's wrath has already been seen, and not just in cold-weather environments. In North Carolina, 6-year-old Emily Grace Muth died within four days of getting sick."She was breathing a little bit heavier than she was. Then all of the sudden she just raised up and went back down...and I noticed she wasn't breathing then," mother Rhonda Muth said.In West Palm Beach, Florida, the virus was too much for a 12-year-old boy, his family said. By the time local sheriff's deputies responded, he was dead.Another school district closed its doors due to increasing flu activity. The schools in Port St. Joe, Florida, kept students at home in order to sanitize all of its buildings.While the new research linking the flu to heart attacks did not look at vaccine effectiveness, the researchers note that vaccines may offer some protection against cardiovascular events. It's another reason to get the shot, if you haven't already.