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Data snapshot: Flu hitting kids especially hard.

Data snapshot: Flu hitting kids especially hard.

This season is like nothing we've seen since 2009 H1N1

Jeremy Faust, MD's avatar
Jeremy Faust, MD
Dec 08, 2022
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Data snapshot: Flu hitting kids especially hard.
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Flu is back. As I wrote the other day, influenza hospitalizations now exceed Covid-19 hospitalizations in many parts of the country, a first since Covid showed up.

After two seasons without a substantial flu outbreak—our Covid mitigation efforts clearly knocked out other less contagious pathogens like flu and RSV—patients and hospitals are getting walloped with flu, and far earlier than usual. If these rates continue, we’re in for a nasty season.

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But the burden of illness is not equally distributed across all age groups. Below are two animations (by Dr. Kristen Panthagani) and five graphs (all based on updated CDC data) showing the running total for influenza hospitalizations per 100,000 people in the United States for every season from 2009-2010 through 2022-2023.

You’ll note two things about 2009-2010, the year of the 2009 H1N1 flu pandemic, in particular. First, that season, influenza showed up very early, even earlier than this year’s outbreak. Second, 2009 H1N1 hit children exceptionally hard. In fact, the older the age group you look at, the less impressive the 2009-2010 flu season was in the United States. The data match with what my colleagues on Twitter remember from that time.

Right now, we don’t know if this year’s flu will exceed what we saw in 2009-2010. But as with that season, the youngest age groups are experiencing the most out-of-the-ordinary rates of hospitalization. Children ages 0-4 are being hospitalized at higher rates than all other age groups except adults ages 65 and up. And even comparing those groups, children ages 0-4 have around 71% the influenza hospitalization rate (per 100,000 people in the population) as adults ages 65 and up.

This year’s flu vaccine is apparently a decent match, apparently around 50% effective, according to the CDC. What I’m trying to say is that now would be an excellent time to get a flu vaccine, if you haven’t already!

Cumulative influenza-associated hospitalizations by season. Data: CDC FluSurv.
Cumulative influenza-associated hospitalizations by season. Data: CDC FluSurv.
Cumulative influenza-associated hospitalizations by season. Data: CDC FluSurv.
Cumulative influenza-associated hospitalizations by season. Data: CDC FluSurv.
Cumulative influenza-associated hospitalizations by season. Data: CDC FluSurv.

A shareable version of these graphs in a single PDF can be found below, and is available to upgraded subscribers. If you can see it and download it, you’re already upgraded! If you can’t and want to, upgrade now (or trial it for free)…

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