Expert Provides Predictions for Trajectory of Vaccine-preventable Disease Outbreaks in US

Pharmacy Times® interviewed Michael D. Hogue, PharmD, FAPhA, FNAP, FFIP, dean and professor at the Loma Linda University School of Pharmacy in California, on his presentation at the APhA 2023 Annual Meeting & Exposition titled “Your Annual Roundup: 2023 Immunization Update.”

Pharmacy Times®: What is your current outlook on the occurrence of outbreaks of vaccine-preventable diseases in the United States?

Michael D. Hogue, PharmD, FAPhA, FNAP, FFIP: Well, I think that one of the things that happened during the pandemic is that we were so focused entirely on COVID that we didn’t think so much about all of the other vaccine preventable diseases that are out there for which we have effective vaccines, and particularly in children and adolescents. And so, the CDC has noted that we're generally behind on getting kids caught up on their vaccinations. And where we run the risk is, if we are not successful at getting children caught up on their vaccinations for things like measles, and haemophilus influenza B, meningitis, and other pretty serious illnesses, that we could have outbreaks of those conditions occurring, either regionally or nationally. So that's my real concern for 2023 and heading into 2024 is that we need to have a real catch up among the American public for all of the things that we might have forgotten about while we were worried about COVID.

Pharmacy Times®: What are your predictions for the trajectory of vaccine-preventable disease outbreaks in the country?

Hogue: Well, I think there's a lot of weariness in the public right now about, quote unquote, new vaccines. Largely, I think that the COVID vaccines, people feel strongly, personally about COVID vaccinations and if you stick to the science on those, we know that they work and that they're preventing people from being hospitalized. But I think that particularly certain adults, particularly adults that are between ages 19 and 64—what I would say the young adult and middle age group—tend to have a little bit more vaccine hesitancy right now than perhaps they did prior to the pandemic. And so those groups, especially if those individuals have chronic underlying conditions like diabetes or asthma, or maybe you have underlying heart failure or heart disease, cardiovascular disease, those individuals may not realize how vulnerable they are, individually, to some of these vaccine preventable diseases. And I'm afraid that that means we may have some unnecessary hospitalizations and deaths, particularly among the 19- to 64-year-olds that would have otherwise been avoided if people would have gotten vaccinated. And particularly worrisome to me is influenza. We now know that there's a direct link between influenza illness and a first-time myocardial infarction in individuals who have underlying cardiovascular disease and may not be aware of it. So, vaccination against flu is the best way to prevent not only the flu but it also prevents heart attacks. And that's pretty strong. In fact, we have data to show that vaccination against influenza is just as effective and prevents just as many heart attacks as giving people statins to control their cholesterol and prevent cardiovascular disease.

Pharmacy Times®: What are some recent changes to the immunization schedules for adults and children?

Hogue: Yeah, so I think the biggest thing to point out on the pediatric adult immunization schedules is that COVID vaccines actually now summarized on the schedules. And I want to point out for people who might be listening that the immunization schedules are not a mandate for vaccination. They don't represent our nation's policy requirements for vaccination for any vaccine. The immunization schedules for pediatrics and adults are intended to summarize the individual vaccine recommendations from CDC in an easy to find location so that everything's summarized in one place. And that's what those schedules are designed to do. So, there are some out there who I think believe that the schedules and the inclusion of COVID on the schedules is a mandate that COVID vaccine has to be used, and that's just simply not true. So, I'd point out that the addition of COVID vaccine on there is very important.

The other thing I’d really like to point out to everybody is that, for the adult vaccination schedule, hepatitis B vaccine is now routinely recommended for all adult patients. And in the past, we really tried to focus hepatitis B vaccination on people who had the highest risk factors for contracting hepatitis B, but despite many, many years—20 or 30 years—of trying to take that approach of just immunizing those who are high risk, we still have found that as many as 5,000 people a year die from hepatitis B in the US and that stat’s not changed. So, the CDC made the decision to recommend that all adults receive hepatitis B immunization series. And I would say that’s probably one of the most important changes that’s happened to the schedule for the adult patient population in this last year.

Pharmacy Times®: What are some of the recently licensed vaccines of note, and how safe and effective are these new vaccines?

Hogue: Well, I think a couple of things to point out is that we want to make sure our vaccine supply is durable and not dependent upon a single manufacturer, so that we can always make sure we're providing vaccines, particularly to kids. For many, many years, we only had one measles vaccine on the market in the US. So, if we ever had a disruption in supply of that measles vaccine, that put us in a pretty vulnerable position. And that became quite evident during the pandemic. One vaccine that has been recently licensed in the US within the last year is a second measles vaccine product. And the safety and efficacy of that product is equal to the existing vaccine that's on the market and can be used interchangeably for measles vaccination, but it represents a really important move in terms of our nation's vaccine supply to now have a second measles vaccine available and out there for our potential use.

Another vaccine that is not yet licensed but will be likely licensed by the FDA in as soon as the late this spring is an RSV vaccine. Respiratory syncytial virus (RSV) came onto the scene with a loud noise in the last 12 months, and most consumers have now become aware that RSV is a thing, even though those of us in health care have known RSV was the thing for a really long time. Vaccine manufacturers have been working on RSV vaccines for the better part of a decade or longer. And finally, those vaccines have gotten through the normal vaccine development pipeline, and there will be likely new pediatric vaccine options, new adult vaccine options, and potentially even a maternal vaccine option. All of those 3 formulations, or 2 formulations for 3 different populations are sitting in front of the FDA, and FDA anticipates making decisions on those by the end of the spring. And so, there's promise and hope that those vaccines will come to market and help us at reducing the number of RSV infections in time for the next RSV season, which parallels our typical cough, cold, flu, and COVID season, typically in the winter months. So those are some of the highlights. There's much more, but I think those hit some of the highlights of changes coming and new vaccines.

Pharmacy Times®: What are some of the current immunization recommendations for COVID-19 vaccinations?

Hogue: So, in short, the recommendation is for all individuals to receive a COVID, a bivalent COVID booster shot. So, essentially, anyone who's been vaccinated against COVID needs to get a one-time bivalent COVID vaccination. And I think what's really important to understand about this is that we know that COVID vaccines are not 100% effective at preventing COVID. Many people will have had a COVID vaccine and then some weeks or months later may actually come down with a case of COVID. But what we do know is that the vaccines are incredibly effective at preventing individuals from having serious COVID, in other words, COVID that requires hospitalization or might cause death. And so, getting a COVID booster now, a bivalent COVID Booster now, is very important.

Just 2 weeks ago, the FDA had a very important public conversation about the future of COVID vaccines, asking pretty critical questions about whether or not we should have an annual change in the formulation for COVID vaccines to reflect what's circulating, much like we do for influenza vaccines. They also discussed whether or not we should have a monovalent vaccine for primary series or if we should shift to just having a single bivalent vaccine and that vaccine be used for primary immunization and for annual booster doses. These are things that continue to be debated, and FDA is looking carefully at the science on this, and the CDC is also having those conversations at the ACIP level about the vaccines. And so I think we'll probably, as the next few weeks wear on, we'll get some real clarity about this. FDA seems to be leaning toward, based upon the public commentary, seems to be leaning on a process where, in the early summer perhaps as early as late May or early June, identifying the components that would be in the next bivalent vaccine and having some sort of an annual update to the COVID vaccine similar to the way we update our flu vaccines. And that's not been decided definitively, but that seems to be where things are headed. And so that's something that we need to pay close attention to. But right now, the key takeaway is everyone needs to have had at least 1 dose of the bivalent COVID booster shot, and that's the core recommendation that's made by CDC.