Dr. Thomas Frieden, director of the Centers for Disease Control and Prevention, got his flu shot in September.
J. David Ake/AP
December 4, 2014 The main flu strain circulating now tends to send more people to the hospital than other strains. It also causes more deaths, especially among the elderly, children and people with health issues.
A hog gets a closeup at the Illinois State Fair in August. Officials took special precautions to make sure no livestock sick with a new strain of swine were part of the fair.
September 11, 2012 An influenza virus that only infects pigs could very quickly lead to a dangerous flu pandemic in humans, a recent study reports. Results of an experiment in ferrets, a model for flu in humans, suggest that a swine flu virus can mutate into a contagious and fatal disease within 10 days.
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