, °F

Radar & Maps

News & Video

Extreme Weather

Social

Personalized Forecasts

A.M. Planner

Home & Garden

Sports & Recreation

Health

Miscellaneous

Featured Forecast

My Favorite Forecasts

    New York, NY

    Local Weather

    My Recent Locations

    Flu shot effectiveness in question as worse-than-normal season looms for US

    By Jillian MacMath, AccuWeather staff writer
    December 19, 2017, 9:05:47 AM EST

    Share this article:


    Signs are pointing to a worse-than-usual flu season this year and it’s too soon to tell whether the shot will be effective in preventing infection, experts say.

    This year, the World Health Organization recommended that the Northern Hemisphere vaccines contain the same strains as those which were used during flu season in the Southern Hemisphere.

    While this strategy sometimes works, it's possible the vaccine will end up being the wrong match for the virus that dominates in the United States.

    flu vaccine

    (AP Photo/Jacquelyn Martin)


    “Australia, where flu season just ended, saw very high levels of influenza activity this year,” according to Nicole Bouvier, MD, associate professor of Infectious Diseases at the Icahn School of Medicine at Mount Sinai.

    Preliminary estimates of vaccine effectiveness were low — overall 33 percent effective in preventing influenza and only 16 percent in preventing hospitalization with influenza.

    “Those two things together suggest that our flu season may be worse than usual and/or the vaccine may be less effective than usual,” she said.

    Typically, the influenza vaccine takes between six and eight months to produce and approve.

    This means recommendations for vaccine strains have to be made in February or March for the following influenza season in the Northern Hemisphere and in September in the Southern Hemisphere.

    By the time data is analyzed from the previous flu season in the Southern Hemisphere, the Northern Hemisphere vaccine is already being administered and it’s too late to change its makeup.

    RELATED:
    Holiday air travel: 5 health risks and tips to avoid them
    Best and worst days, times to travel during the Christmas holiday
    Winter solstice: Everything you need to know about the shortest day of the year

    “All of this is essentially speculation, albeit evidence-based speculation — the only thing predictable about influenza is its unpredictability,” Bouvier said.

    So far, the U.S. is mostly being affected by the A(H3N2) strain of influenza - the same as that which impacted Australia.

    The good news is that most of these viruses have been similar to the vaccine strain, meaning there are reasons to believe this year might not be a complete “vaccine mismatch,” according to Bouvier.

    Experts say it could be weeks or months until it's clear whether the current vaccine is working well.

    In the meantime, the Centers for Disease Control (CDC) continue to recommend the public gets vaccinated.

    “It’s important to remember that the flu vaccine is designed to protect against three or four flu viruses, depending on the vaccine,” they said. “For these reasons, even during seasons when there is a less-than-optimal match, CDC continues to recommend flu vaccination.”

    This is particularly important for high-risk individuals, including children under age 5, adults over 65 and pregnant women.

    Report a Typo

    Weather News
    >

    Comments

    Comments that don't add to the conversation may be automatically or manually removed by Facebook or AccuWeather. Profanity, personal attacks, and spam will not be tolerated.

    More Weather News

    More Weather News

    TRENDING NOW

    Kenny Babb

    In case you missed it: Florence leaves devastating flooding in Carolinas; Deadly Typhoon Mangkhut creates apocalyptic scenes in Philippines, China

    The Carolinas continue to deal with Florence's aftermath while flooding inundated other parts of the U.S. this week.

    Read Story
    943x617_10271359_fal-foliage

    Most vibrant fall foliage in the US predicted to grace the Northeast this year

    Forecasters are calling for an excellent fall foliage season in parts of the Northeast this year, thanks to ideal weather conditions over the summer.

    Read Story
    More Trending Now
    >