CHEST 2025: Advancing Respiratory Virus Vaccines and Improving Uptake Among High-Risk Populations

Kristina Crothers, MD, professor in the division of pulmonary, critical care and sleep medicine at the University of Washington, sat down with Pharmacy Times® at CHEST 2025, held in Chicago, Illinois, to discuss recent progress in vaccines targeting respiratory viruses such as influenza and respiratory syncytial virus (RSV).

Crothers highlighted advancements including pre-fusion RSV vaccines, high-dose and adjuvanted influenza vaccines, and the development of mRNA platforms that enable faster and more targeted responses to emerging strains. She also emphasized the importance of provider communication and trust in improving vaccine uptake, particularly among hesitant or high-risk patient populations.

Although employed by the US Department of Veterans Affairs (VA), Crothers is not representing the VA, and the views expressed are her own.

Pharmacy Times: What are the most significant recent advancements in vaccines for respiratory viruses like influenza and RSV?

Kristina Crothers, MD: I'm Kristina Crothers. I'm a professor at the University of Washington in the Division of Pulmonary, Critical Care, and Sleep Medicine.

Pharmacy Times: What are the most significant recent advancements in vaccines for respiratory viruses like influenza and RSV?

Crothers: I think one is, first, just having a vaccine for RSV. Earlier on, the studies actually showed worse outcomes in people who were vaccinated with the very early vaccines, and that stalled development of RSV vaccines for quite a while. Now, having the pre-fusion vaccines has allowed much better vaccines for RSV to be developed, so I think that is one really significant advancement.

For influenza, there are mRNA vaccines in development. We don't currently have them in use yet, but having the higher-dose and adjuvanted influenza vaccines is also a great development.

Pharmacy Times: How are newer vaccine designs improving protection for high-risk populations?

Crothers: One is the higher-dose influenza vaccine, adjuvanted protein vaccines, and then the mRNA platforms, which are allowing more rapid development of different vaccines. The pre-fusion F protein vaccines, which are currently only available for RSV, are also being looked at for other viruses.

All of those are helping with better immunogenicity, and some of them, like the adjuvanted protein ones, potentially have a longer durability of response. Those can all be better for older patients and patients who are immunocompromised.

Pharmacy Times: What progress has been made in clinical trials for emerging respiratory virus vaccines?

Crothers: One of them is the development of mRNA vaccines for influenza, which are in clinical trials and so far appear to be safe. That will allow us to target and develop the vaccines more quickly and hopefully target the strains that are going to be in circulation, rather than having to guess ahead of time and then wait as the vaccines are developed and hope that it turns out to be the right target.

There are also early clinical trials looking at vaccines for human metapneumovirus and for parainfluenza.

Pharmacy Times: What strategies can help improve vaccine uptake and implementation in clinical practice?

Crothers: That’s a tricky question. I think at the individual provider level, it’s important to talk to all of our patients about vaccination. Sometimes you can normalize it by saying, “You’re due for this vaccine,” and talk about it as part of routine preventative care for patients.

We also have patients who are more hesitant to accept vaccines. If that’s someone who has had concerns in the past, it’s good to have a dialogue with them. Often, it involves using motivational interviewing techniques and trying to elicit their concerns. I ask my patients, if I know they have refused a vaccine in the past, why—what are their concerns? That way, you can try to address those concerns and share with them the evidence supporting the use of a vaccine.

If they’re concerned about side effects, discuss the risks of those side effects and weigh them against the risks of getting infected with that virus or bacteria. Through shared decision-making and discussion of the risks and benefits, you can hopefully encourage them to accept the vaccine.

It particularly helps if you have a relationship with that patient. Many studies have shown that getting recommendations from a trusted provider is one of the things that convinces patients to accept a vaccine. If they accept one vaccine, it doesn’t necessarily mean they’ll accept another, so it’s often necessary to talk about each individual vaccine as well.