Trending Clinical Topic: Influenza

Ryan Syrek


February 14, 2020

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Although news about the novel coronavirus outbreak originating in China has dominated headlines, concern about the activity of another deadly virus is on the rise. According to the World Health Organization (WHO), influenza causes nearly 5 million cases of severe illness worldwide each year that kill as many as 650,000 people. According to the US Centers for Disease Control and Prevention (CDC), as of late January, the 2019-2020 flu season has seen 19 million illnesses, 180,000 hospitalizations, and 10,000 deaths in the United States. After a slight decrease over the winter holidays, influenza activity is once again on the rise.

Unfortunately, the CDC reports that this season's vaccine was not a good match for the B/Victoria strain, which is the predominant virus in the United States this year and the strain that is hitting children especially hard. According to the WHO, influenza A is more dominant than influenza B worldwide; A(H1N1)pdm09 has accounted for 58.8% of the A viruses, with B/Victoria accounting for 98.6% of the B viruses.

Despite the mismatch, vaccination is still beneficial. With the flu season still ongoing, vaccination remains strongly recommended by various organizations, including the Advisory Committee on Immunization Practices (ACIP) of the CDC. That organization recently released an updated schedule for adult vaccines, including influenza. The ACIP recommends routine influenza vaccination for all persons aged 6 months or older who have no contraindications. Where more than one appropriate option is available, the ACIP does not recommend one product over another. Other major updates include increasing the recommended age for catch-up immunization against the human papillomavirus (HPV) to 26 years for men and women, and no longer routinely recommending the pneumococcal 13-valent conjugate (PCV13) vaccine for all persons aged 65 years and older.

In other flu vaccine news, concern about a possible pandemic prompted the US Food and Drug Administration (FDA) to approve a novel vaccine designed to provide active immunization against the influenza A virus H5N1 strain. It is for use in individuals aged 6 months and older, can be rapidly deployed, and may be stockpiled by first responders in the event of a pandemic.

Although influenza may be more familiar than the coronavirus, concerns about its activity and news related to vaccination got many people's attention, making it this week's top trending clinical topic.

Read more about influenza.


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