The United States has never recorded so many positive flu tests in one week

This is flu season fierce start it has given way to record-breaking and massive levels of broadcasting strain on the American health care system.

In the week ending Nov. 26, more than 34,000 positive flu tests were reported to the Centers for Disease Control and Prevention (CDC) by laboratories across the United States, as shown in the orange line in the graph below. These are more positive flu tests than reported in a single week during any recorded flu season since 1997.

The trajectory dwarfs the past six flu seasons, including the relatively bad 2019-2020 that immediately preceded the onset of the Covid-19 pandemic (shown in the black line).

Keren Landman and Rani Molla

Part of this sharp increase in cases is related to more people being tested for the flu than in previous years. In November, approx twice as many flu tests were performed in clinical laboratories nationwide as in the same period last year (about 540,000 versus 265,000). More tests mean more cases will be collected.

However, there are corroborating warning signs that this is indeed a bad season. Influenza hospitalizations have been off the charts and are increasing rapidly. In a news conference on Monday, CDC director Rochelle Walensky said they’ve been there before 78,000 hospitalizations for influenza this season, or nearly 17 per 100,000 Americans. That’s “the highest we’ve seen this time of year in a decade,” she said. In line with past trends, the highest hospitalization rates are among adults aged 65 and over.

Keren Landman and Rani Molla

What makes these high hospitalization rates particularly concerning is their overlap with spikes in other viruses that cause many people to become sick enough to require hospitalization. One of them is RSV, which has been filling children’s hospitals for more than six weeks. And while Walensky noted there were signs that RSV transmission was slowing in some parts of the country, hospitalizations for Covid-19 have recently started to decline TIC Tac upward.

An important reason for the convergence of these viral waves: low levels of antibodies in the whole population against many common colds and flu. Pandemic-era preventative measures delayed first infections among many children, which, while good for the health of individual children, meant that a higher than usual number were susceptible to serious infections when those preventative measures were lifted. (Read more about the concept of “immunity debt” and how it can be dangerously misunderstood here.)

We can still flatten the flu season curve

Even Americans aren’t doing everything they can to protect themselves from respiratory viruses: just a quarter of adults and 40 percent of children received a flu shot this season, e 15 percent of adults eligible for an updated Covid-19 booster dose received one.

This represents major missed opportunities for prevention: This year’s flu vaccine is expected to be particularly effective, Walensky noted, as it fits well with circulating flu strains, which vary from year to year. However, it only works if people understand it.

Also, many of the preventive measures tried effective during the Covid-19 pandemic they have remained largely unused, although they would also be useful in preventing the spread of other respiratory diseases. There hasn’t been a major push to implement a high standard of ventilation and filtration inside US buildings. Only a quarter of Americans have it changed their behavior to reduce viral exposure. And a minority of Americans often wear masks outside the home.

Between the flu wave, drug shortages they are complicating efforts to prevent serious illnesses and treat bacterial infections that can follow in the wake of some flu infections. Furthermore, staff shortages that have intensified as a result of the pandemic have put children’s hospitals in a position to care for a massive wave of sick children with even fewer resources than they had before. Although pediatric health organizations have asked a declaration of national emergency to support their response to this wave, no one has been forthcoming.

In the United States, influenza infections normally peak between December and February. It remains to be seen whether the current wave of early flu will result in an early flu peak or instead predict a sustained period of extraordinarily high viral transmission, with ever more crushing burdens on healthcare workers as more people become seriously ill.

After a punishing few years, it’s unclear how much further strain America’s healthcare system may absorb.

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