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Three Respiratory Diseases Converge for a Tough Cold and Flu Season

By Elaine K. Howley
Feb. 7, 2024

Despite widespread availability of safe, effective vaccines, cases of respiratory illnesses including COVID-19, flu, and RSV have spiked this winter, threatening to strain the health care system yet again.

Close up of a mature man taking a vaccine in his doctors office.

If it feels like everyone around you has recently gotten some sort of respiratory illness — whether that’s COVID-19, influenza, or respiratory syncytial virus (RSV) — it’s not your imagination. The United States has seen a surge in cases of all three of these infectious diseases in recent months.  

The uptick has been alarming, especially because there are now safe, effective vaccines available to combat these viruses.

Unfortunately, too few people are getting the shots, leading the Centers for Disease Control and Prevention (CDC) to issue an alert on Dec. 14 warning of an impending surge of critically ill patients who could strain health care systems — a warning that, in fact, proved prescient.

The week ending Dec. 30, 2023, posted some of the highest rates of COVID-19 and influenza hospitalization in a year. RSV hospitalization rates also peaked in the week ending Dec. 30, 2023. While those rates have declined slightly, the CDC continues to encourage health care providers to push vaccination for all patients who are eligible for these potentially lifesaving interventions.

Demetre Daskalakis, MD, MPH, director of the CDC’s National Center for Immunization and Respiratory Diseases, notes that despite the fact that “we have more tools than ever for people to protect themselves against serious illness, they only work if they’re … getting into the arms” of everyone who’s eligible to receive them.

The Scope of the Problem

Daskalakis notes that “big picture, we’re in the middle of respiratory season,” which is a loosely defined period that generally runs from November to March. Those typically are the coldest months in most of the United States, and that’s when many people head indoors where pathogens can more easily spread from one person to another.

It’s a well-established pattern with flu and many cold viruses. With COVID-19 and RSV, that seasonality seems a little less entrenched, Daskalakis says, but there have been upticks in those infections during the same period as well.

These early trends were concerning enough for the CDC to issue that health alert in mid-December. “We made a call to action that ‘it’s not too late to vaccinate, vaccinate now,’ because all of our projections showed that this season could be as bad as last season or maybe potentially a little worse,” Daskalakis says.

Part of the issue is a lower-than-ideal uptake of vaccinations against all three of these viruses. The CDC tracks vaccination rates closely and reports on a weekly basis. As of Feb. 2:  

  • 21.8% of adults and just 11.6% of children reported having received an updated 2023-24 COVID-19 vaccine. (Data from the CDC’s COVID Data Tracker noted that as of May 10, 2023, 20.5% of adults aged 18 and older had received the first bivalent COVID-19 booster, which was initially released in September 2022.  Among children aged 5 to 11 years, the rate was 18%. The total rate for that bivalent booster dose coverage was 17.0%.)
  • 47.1% of children and 48.4% of adults aged 18 and older had received this year’s flu vaccine. Among adults aged 65 and older, that rate was much higher, at an encouraging 72.8%. (By comparison, the flu vaccination coverage rate in the 2022-23 season among children between the ages of 6 months and 17 years was 57.4%. Among adults aged 18 and older, the rate was 46.9%.)
  • 20.8% of adults aged 60 and older reported receiving an RSV vaccine. (Because this vaccine debuted with the 2023-24 season, no comparative data from the previous season is available.)

While data from Feb. 2 show that hospitalizations related to COVID-19, flu, and RSV had declined from their highs December, they remained elevated throughout most of the country. Deaths related to COVID-19 and flu declined somewhat over the previous week, while RSV death rates held steady. 

In his practice, William Schaffner, MD, professor of infectious diseases at Vanderbilt University Medical Center in Nashville, Tennessee, says “the CDC data reflect what’s happening here in our neck of the woods. Namely, that the leader at the moment, if you will, is influenza, which is very active across the United States and started first and very vigorously here in the Southeast. But every part of the country is currently involved,” he notes.

“It does look as though we’re headed toward a moderately severe influenza season, and we’re seeing our emergency department, our staff clinics, the comments from practicing pediatricians and internists, and hospitalizations — they’re all very active with influenza at the present time,” Schaffner says. 

He adds that the RSV season “started a bit early this year” and then plateaued in much of the country. “That’s what it’s doing with us, although it’s keeping pediatricians and emergency rooms very busy in some parts of the country.”

Preventive Tools Exist

The rise in any of these diseases is frustrating for many in the public health sphere because there are reliable and widely available vaccines that can prevent or reduce the severity of infections.

But not everyone is on board with some or all of these vaccines, and Schaffner says “the public has not accepted influenza vaccine to the same extent as it did pre-COVID. So, we are underutilizing the influenza vaccine.”

That’s true of the COVID-19 vaccine as well, which Schaffner says is “stunningly underutilized.”

With RSV, “that vaccine is brand new” and some people may not realize they’re eligible for it. Currently, it’s advised that people age 60 and older talk with their doctor for advice on whether they should take the RSV vaccine. Pregnant people are advised to get the RSV vaccine between weeks 32 and 36 to offer their forthcoming child protection right from the start.

Addressing Barriers to Vaccination

There are myriad reasons why vaccination rates aren’t higher, and a big one Schaffner cites is vaccine fatigue. In the post-pandemic world, many people want to just move on and not think about infectious diseases anymore.

“We’ve had some spillover of vaccine fatigue into the flu and it’s slowed a little bit the uptake of the RSV vaccine. So, we’re going to have to work our way through this not only this season, but in subsequent seasons,” he says.   

But that doesn’t mean there’s nothing to be done right now, and many providers have found that constantly ringing the vaccination bell can help bring people around. Sometimes it takes more than one conversation for a patient to agree to a vaccination, and some proven techniques can help boost acceptance.

The CDC has produced a new conversation guide that health care providers can use to talk with patients about why they should accept vaccines against COVID-19, the flu, and RSV. Some highlights from that guide and tips from practitioners include:

  1. Recommend vaccination.
    “The single most effective way to have a patient accept immunization is when they get a strong — and I emphasize strong, not casual — recommendation from their health care provider,” Schaffner says. “That recommendation should also be reassuring and comforting that it’s a good and right thing for the patient to do for themselves, their family, and their whole neighborhood and community.”
  2. Tell them the vial has their name on it.
    Instead of telling a patient that “it’s time to start thinking about getting a vaccine — which is an invitation to leave the office unvaccinated,” Schaffner notes, be firm and say, “it’s time for your shot and my assistant will take care of that for you before you leave today,” he says. “The implication is, it’s right there in the fridge with your name on it, so surely you’re going to get it.”
  3. Normalize vaccination.  
    Schaffner also says that being “self-referential” and explaining that he has accepted the vaccine, too, can help sway people. “You can normalize it when everybody’s doing it because it’s the right thing and we’re all in this together.”
  4. Remind, remind, remind.
    Everyone gets sidetracked, and sometimes the easiest way to get someone to accept a vaccine is to just perpetually remind them until they finally follow through. You can set up reminders that get sent to patients via your practice’s electronic records system. When someone comes in for any reason, take that opportunity to get them vaccinated.

    Daskalakis likens it to other screenings. “When I see patients, I think about the person who you’ve told for three visits in a row ‘you need a colonoscopy,’ and they blow you off until the fifth time, they just take you up on it. And sometimes this is the same for vaccines. If at first you don’t succeed, just keep trying.”
  5. Talk with your patients.
    Jesse Goodman, MD, MPH, director of the Center on Medical Product Access, Safety and Stewardship and an attending physician in infectious diseases at Georgetown University and DC Veterans Administration Hospitals, recommends spending that extra few minutes with patients to hear their concerns and answer questions.

    Often, they just need someone to talk things out with and their doctor is likely the most trusted source for health information. “Unfortunately, in the care system, everybody’s pressed for time, and there’s not time to talk with people. But more and more, we could probably save a lot of lives if we spent a little more time talking.”
  6. Address side effects honestly.
    Every medical intervention has potential side effects and with vaccines, it’s important to acknowledge them while emphasizing that they are typically mild and resolve in a couple of days.

    evere side effects are rare, and, as Goodman notes, the mild side effects that can happen with a vaccine are nearly always significantly less severe than getting the illness without vaccine coverage.
  7. Address misinformation directly.
    Particularly for the COVID-19 vaccine, which is just a few years old, and the RSV vaccine which debuted this season, many people have some hesitancy about the vaccines’ newness, and the implication is that that makes them dangerous or untested. Misinformation abounds, and it’s important to address that directly, Goodman says. “There’s just a need for constant education because there’s a lot of misinformation out there.”

    Another common issue is that “people somehow don’t perceive themselves to be at risk,” even when they might be in a higher risk category, Goodman says. Underscore that vaccination reduces risk of getting sick and it’s been shown to reduce the severity of illness when someone is infected.
  8. Offer context.
    Daskalakis notes that 700 million people have been vaccinated against COVID-19 and billions have been vaccinated against the flu. “This is powerful evidence that these vaccines are safe,” he says.

    Goodman adds that “flu vaccines have been around for 70 years and are extremely safe.”
  9. Explain the individual’s risk level.
    Not everyone has the same risk profile for infections, and while everyone should vaccinate in accordance with their advised schedule, for the most vulnerable, this becomes even more important.

    For example, pregnant people “are at really high risk for hospitalization with flu, and immunization can be beneficial,” Goodman says.
  10. Remember your superpower — Trust.
    Lastly, Daskalakis says it’s important for providers to remember the trust they’ve built through the patient-doctor relationship. You also have more tools in your toolkit than you might realize in reaching people and convincing those who might be hesitant to accept a vaccine — from e-reminders to signage in the building, you have many ways of getting your message across. “Realize your power in terms of talking to patients and really teach them how to protect themselves best against these viruses.”

The New Normal

Seasonal uptick in respiratory infections is nothing new, but having three major infectious diseases in circulation all at once is the new normal that health care providers and hospital systems are having to accommodate.

As always, prevention is a great way to avoid bad outcomes, and to that end, experts are reminding everyone to keep up with the behaviors they know can help, including:

  • Washing your hands frequently.
  • Avoiding crowded indoor spaces.
  • Wearing a mask if you’re heading into a crowded indoor space. Some health systems have mandated masking in hospitals and other health care settings in recent months as well, as cases of COVID-19, flu, and RSV have risen.
  • Staying at home if you’re ill to avoid spreading germs.

With both COVID-19 and influenza, effective antiviral treatments can be used to shorten the duration of the illness, but they must be deployed early in the course of the illness. This is why Goodman recommends getting a diagnosis when you’re sick, especially if you’re immunocompromised or otherwise more vulnerable to infection.

And while the worst of this season’s respiratory virus spike may be easing slightly, Schaffner notes that it’s never too late to get vaccinated. These viruses are in constant circulation, and cases of COVID-19, flu, and RSV can be diagnosed at any time of the year. Those who remain unvaccinated risk getting sick and passing that infection on to more vulnerable people in the community.