As this year’s flu season gathers steam, doctors and pharmacists have a fresh stock of vaccines to offer their patients. The vaccines usually provide strong protection against the virus, but only for a while. Vaccines for other diseases typically work for years or decades. With the flu, though, next fall it will be time to get another dose.
“In the history of vaccinology, it’s the only one we update year to year,” said Gary J. Nabel, the director of the Vaccine Research Center at the National Institute of Allergy and Infectious Diseases.
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