Von Lipinski's story is typical of what Dr. William Schaffner, chairman of the Department of Preventive Medicine at Vanderbilt University Medical Center, knows of these sorts of infections.

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But Dr. William Schaffner, chairman of the Department of Preventive Medicine at the Vanderbilt University Medical Center, estimates there are fewer than 250 cases every year in the United States.

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Simply put, it's a clearer policy, and some protection is better than none at all, according to Dr. William Schaffner, the chair of the department of preventive medicine at Vanderbilt University.

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Dr. William Schaffner, chairman of the Department of Preventive Medicine at the Vanderbilt University Medical Center, estimates that fewer than 250 such cases occur each year in the United States, though estimates are imprecise since doctors do not have to report the cases to health authorities.

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Dr. William Schaffner, chairman of the Department of Preventive Medicine at the Vanderbilt University Medical Center, estimated that fewer than 250 such cases occur each year in the United States, though estimates are imprecise because doctors do not have to report the cases to health authorities.

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Though there is uncertainty about just how common such infections are since no clearinghouse compiles statistics on their incidence, Dr. William Schaffner, chairman of the Department of Preventive Medicine at the Vanderbilt University Medical Center, estimates there are fewer than 250 cases every year in the United States.

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It can prevent the flu, and it can be beneficial even if you do get sick, said Dr. Bill Schaffner, chairman of the preventive medicine department at Vanderbilt University's School of Medicine.

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