About half of influenza A (H3N2) viruses—the season’s most prevalent—are different from the H3N2 virus included in this season’s flu vaccine. As a result, the Centers for Disease Control and Prevention (CDC) warns that this year’s vaccine might be less effective against these versions of the virus. CDC recommends the following three-pronged approach to protect against the flu:
- Get the flu vaccine. While it might only provide partial protection against some versions of the virus, it should better protect against others, including influenza B viruses.
- Take antiviral medications as a second line of defense against the flu. Antiviral medications work best when taken within two days of the onset of flu symptoms.
- Use other safety precautions, including staying away from sick people and washing your hands often.
CDC notes that the use of antiviral medications is especially important this season because the vaccine might be less effective.
Several key resources, including information specifically for health professionals, question-and-answer documents, and additional information about treatment and prevention are available on the CDC’s flu resource page.