Every fall and winter, viral respiratory illnesses like the common cold and seasonal flu keep kids out of school and social activities. But this year, more children than usual are ending up at emergency departments and hospitals.

In California, the Orange County health department declared a state of emergency in early November 2022 due to record numbers of pediatric hospitalizations for respiratory infections. In Maryland, emergency rooms have run out of beds because of the unusually high number of severe respiratory syncytial virus, or RSV, infections. So emergency departments there are having to refer patients across state lines for care.

In the U.S., the winter respiratory virus season started earlier than usual this year. Since peak infections usually occur in late December or January, this uncharacteristic early wave suggests that the situation could get much worse for people of all ages, particularly children.

We are epidemiologists with expertise in epidemic analysis for emerging disease threats, including respiratory infections. We watch patterns in these infections closely, and we pay particular attention when the patterns are unusual. We’ve grown increasingly concerned about the amount of pediatric hospitalizations over the last few months and the pattern that is emerging.

In early November, the Centers for Disease Control and Prevention issued a health advisory about increased activity in respiratory infections – especially among children. The CDC and other health experts are warning of the so-called “triple threat” of respiratory illness from RSV, influenza – or the seasonal flu – and COVID-19.

The underlying reasons for the convergence of these viruses and the increase in infections so early in the season are not yet clear. But health experts have some clues about contributing factors and what it could mean for the coming months.

When it comes to COVID-19, 2022 is expected to usher in another winter wave of infections, similar to patterns seen in 2020 and 2021. Previous winter surges stemmed from a combination of factors, including the emergence and spread of new viral variants, more people gathering indoors rather than distanced outside, and people coming together for the holidays.

But unlike previous pandemic winters, most COVID-19 precautions – such as using masks in public areas or avoiding group activities – are more relaxed than ever. Together with the looming threat of new variants, it is difficult to predict how big the next COVID-19 wave could be.

And while the seasonal flu has proved somewhat unpredictable during the COVID-19 pandemic, it nearly always hits during late October. Flu season also arrived about a month early and in greater numbers than in recent history. By our read of the data, pediatric flu hospitalizations are nearing 10 times what has been seen for this time of year for more than a decade.

RSV infections tend to follow a similar seasonal pattern as the flu, peaking in winter months. But this year, there was an unexpected summer wave, well before the start of the typical fall respiratory virus season.

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