In the air

Navigating the new normal of respiratory virus season

I hope you all had a wonderful Thanksgiving. There’s no Outbreak Outlook this week due to the holiday. Instead, I adapted this piece from remarks I gave recently at an event hosted by the Duke-Margolis Health Policy Center. Next week, I’ll be back in your inbox as usual with an update on what’s going around.

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It’s that time of year again. Flu season. It's comes around every year, yet each turn brings its own unique challenges and lessons. It’s not just a topic for epidemiologists. Influenza, RSV and Covid-19 affect our families, our work, and our healthcare systems. Everyone has a stake in figuring out how to reduce the burden of respiratory viruses.

Better Than Last Year

Last year’s tripledemic was a tough one. A surge in respiratory viruses began in late summer and lasted through the winter months. It was hard on families with young kids, healthcare workers, and everyone in between.

The tripledemic likely flared because many of the usual pathogens, like influenza and the common cold, were suppressed thanks to mask-wearing and social distancing during the 2020 and 2021 seasons. But when preventative measures eased, those viruses came back with a vengeance, creating a surge that the health system struggled to manage.

The good news? This year is shaping up to be a bit more manageable. We're not seeing the same level of early virus activity. And although that's a relief, it doesn't mean that this year’s season won’t be disruptive. It will—because most are.

Current Trends

When we talk about seasonal respiratory viruses, there are three big threats: influenza, RSV, and Covid-19. As regular readers of Force of Infection will know, all three are in play right now. To recap:

• Influenza: Flu season came early again this year for some parts of the country. In the Southern region, for example, influenza-like illness is already at levels normally seen in late December. Other regions of the country are on a more normal timeline, meaning activity is just now beginning to pick up. Regardless, it is children (particularly those under four) who are most affected, with much more illness compared to older age groups. This creates a domino effect—sick kids mean disrupted routines, missed school days, and parents struggling to juggle work and caregiving.

• RSV: This year’s RSV season is shaping up to be nearly as bad as 2022. The Southern region of the country is currently bearing the brunt of it, with rates similar to last year's peak season trends. This isn't just a regional issue, though. We're starting to see signs that the Northeast, Midwest, and West might soon follow suit with their own upticks in RSV activity.

• Covid-19: For now, Covid-19 remains active but not especially so. We're not in the clear, but we're not in the thick of it either. After a small surge in the summer, cases dipped, and now we're seeing numbers creep up again. This is a pattern we've become familiar with over the past couple of years—a rise in cases through the autumn months, culminating in a peak around January.

One other thing. When we talk about a 'normal' respiratory virus season, we must remember that 'normal' doesn't mean 'easy.' In the pre-Covid era, our healthcare system often endured significant strain during the winter season. Hospitals and clinics were often slammed, and healthcare workers strained under the increased load. Now, add Covid-19 to the mix, and the situation becomes even more complex. A typical season now means dealing with the flu, RSV, and Covid-19 simultaneously, and that is no small thing.

Vaccination Uptake: Not great

So what do we do about it?

Non-pharmaceutical measures like masking and improving ventilation work to reduce transmission of all three of those viruses. But this year, we have an expanded vaccine toolkit, too. This is the first season that shots are available to protect against influenza, Covid-19 and RSV (for infants and older adults). While I don’t expect any of these shots to reduce transmission, they do work to prevent severe illness. That could, in theory, keep people out of the hospital and reduce burden on healthcare systems.

The bad news is that the current uptake numbers are, frankly, poor. By November 11, only about 36% of adults had received the annual flu vaccine. The Covid-19 vaccine coverage was even lower, at around 15%. For the RSV vaccinations for older adults, coverage is similar at 14%.

Perhaps more alarming is the public sentiment towards these vaccines. A staggering 40% report hesitancy or outright refusal to get the Covid-19 vaccine.

These numbers aren't just meaningless statistics. It’s a big red flag. We’ve got to get the word out about the benefits of vaccination and address the misinformation (or missing information) that often fuels vaccine hesitancy. Improving these figures is important not just for overcoming the current season's challenges but for fortifying our defenses against future outbreaks, too.

Surveillance of Lesser-Known Viruses

Beyond the well-known culprits, there's a whole other category of respiratory viruses that fly under the radar. We live with adenovirus, parainfluenza, human metapneumoviruses, and the seasonal coronaviruses, to name a few, yet we know relatively little about those bugs. Our surveillance of them is quite limited, and we have a minimal understanding of their spread, behavior, and impact. We should improve our surveillance and research into these lesser-studied pathogens, too. Filling in the gaps in our knowledge could help us find ways to reduce the burden of these bugs, too.

And besides, better disease surveillance for respiratory viruses could help us to prepare more effectively for the next epidemic threat. Think of it as shining a light on the 'viral dark matter' that surrounds us. Enhanced surveillance of everyday infections would be a step forward in how we approach public health in the context of all respiratory illnesses.

Dall-E has gotten pretty good.

Moving Forward

So, where do we go from here? First and foremost, we must recommit to a data-driven approach. Data is a tool that can guide our actions, ensuring we are responsive, and effective, in our work. By leading with timely data, we can understand the scope of public health challenges more clearly and tailor our interventions accordingly. That’s why I write this newsletter, and why I want to see metrics and targets used more often in outbreak response.

And this isn't just a job for epidemiologists and policymakers. It's a community effort. Each one of us has a role to play, whether it's staying informed about what’s going around, helping friends and family get vaccinated, or upgrading our surveillance systems. Our response to these public health challenges needs to be collaborative and ambitious. We've seen progress, but there's more work to be done. By learning from our experiences and staying adaptable, we can both navigate the current season and also build stronger defenses for the future.