( CNN ) -- The number of confirmed H1N1 flu cases worldwide surpassed 10,000 , the World Health Organization said Tuesday . In the United States , at least 5,469 cases of swine flu have been reported . Commonly known as swine flu , the outbreak has sickened 10,176 people and caused at least 80 deaths , mostly in Mexico , the organization said . The actual number of people affected may be higher , as it takes time for national governments to confirm cases and report them to the global body . In the United States , at least 5,469 cases of swine flu have been reported , according to the latest figures from the Centers for Disease Control and Prevention . The CDC has linked six deaths to the outbreak ; health officials in New York have connected a seventh death -- a school official -- to the disease . Concern about the disease deepened Tuesday , even as authorities have said the outbreak may prove to be less severe than first suspected . A 44-year-old man died Tuesday in suburban St. Louis , Missouri , according to John Shelton of the St. Louis County Health Department . The man , whose name was not released , had been hospitalized for the past few weeks . He had visited Mexico and tests showed he had swine flu , Shelton said . However , the county medical examiner will determine the cause of the man 's death . In New York , medical investigators determined that the death of a 16-month-old boy in Queens was not linked to the flu . The boy had a fever when his mother brought him to a hospital Monday and he died less than an hour later , drawing attention from investigators . That death came a day after an assistant principal from New York died after contracting the H1N1 virus . That man -- Mitchell Wiener -- had an underlying health condition , said Dr. Thomas Frieden , New York City 's health commissioner and President Barack Obama 's pick to lead the CDC . Wiener died Sunday of complications of the H1N1 virus , hospital and state officials said . If confirmed by the CDC , Wiener 's death would be the seventh linked to swine flu in the United States . The CDC has confirmed three in Texas , two in Arizona and one in Washington state . Wiener 's school is among a handful in New York that temporarily closed at the recommendation of the city 's Health Department . Frieden said Sunday that `` with the virus spreading widely , '' closing affected schools `` will make little difference in transmission throughout New York City , but we hope will help slow transmission within the individual school communities . '' The flu strain , which originated in Mexico , killed dozens of people there , causing U.S. officials to worry that it could take a similar toll north of the border . So far , however , it has acted similar to typical seasonal influenza , which usually can be treated successfully but can be deadly among the very old , very young and people with pre-existing health problems . CNN 's Kara Devlin and Mary Snow contributed to this report .
H1N1 flu has caused at least 80 deaths , mostly in Mexico . Man in St. Louis , Missouri , may be latest to die of flu in United States . Officials say flu is behaving similar to typical seasonal influenza .