Here & Now

A COVID-19 Vaccine Study for Children

Frederica Freyberg:

Lots of action on COVID vaccines this week. The FDA and CDC have approved additional booster shots and vaccines for children aged 5-11 are expected to be approved by early November. In anticipation of that, the Biden administration this week released a plan to get shots in the arms of younger children. The administration reports it has enough vaccine for the 28 million children in the 5 to 11-year-old group. Additionally, the roll-out plan includes making the vaccine available through doctors’ offices, hospitals, pharmacies, and schools and community clinics. For more on these developments, we are joined by Dr. William Hartman who leads clinical trials for COVID vaccines and treatment therapies at UW School of Medicine and Public Health. Doctor, thanks very much for being here.

William Hartman:

Thank you.

Frederica Freyberg:

So I want to talk about boosters in a second, but how key is it in your mind to get this younger age group vaccinated?

William Hartman:

I think it’s very important, especially as we have been so infected with the Delta variant and the Delta variant really was preying on people who are unvaccinated. This age group obviously did not have the vaccine available to them, so we saw the numbers beginning to really increase in terms of infections in this age group. At one point they made close to 30% of all new infections. And so even though they don’t tend to get nearly as ill or die as often from COVID-19, they are still able to spread this to other people, especially vulnerable people. And so getting this age group vaccinated is really a key part of getting the pandemic under control.

Frederica Freyberg:

Given the resistance, though, on the part of a certain segment of the population about vaccines, what can you tell us about the safety of COVID vaccines for children?

William Hartman:

So a lot of work has gone into finding the optimal dose of these vaccines for the children so that we can really have the safest vaccines available. And so the Pfizer vaccine will be a third of the adult dose. The Moderna vaccine will be 50% of the adult dose. So this lessened dose will hopefully lead to overall increased safety, less side effects seen. Thus far in the clinical trial data presented by Pfizer, the number of side effects has been less and they haven’t seen any of the serious side effects that they saw in very few kids in the teenager group.

Frederica Freyberg:

So you’ve been doing pediatric trials on the Modern vaccine. Where does this possibly and probably release of the Pfizer vaccine for children leave your work?

William Hartman:

So with the Moderna vaccine, we’ll keep forging ahead. We want to have as many vaccines available really so that the data can be used worldwide, so we can have these vaccines available to kids all throughout the world. Moderna is going to be a big part of that. The age group, the 5 to 11-year-olds, the enrollment period is just about finished for that, so that data will be interpreted over this next month or month and a half, followed up on, make sure that everything is safe and that the effectiveness is determined and then hopefully by the first of the year a second vaccine, the Moderna one, could be available to this age group as well.

Frederica Freyberg:

As to additional booster vaccines now approved, who are these important for?

William Hartman:

Boosters right now are approved for essentially three groups. So the over 65, the most vulnerable people to COVID-19. The people 18 to 65 who have a co-morbid condition. And the people who have a job that gives them a high exposure to COVID-19. These are the people that they’re focusing on getting these boosters to. The vaccine initial series, whether you got Johnson & Johnson, Pfizer or Moderna, really provides excellent safety and effectiveness against hospitalization, severe disease and death from COVID-19. But getting the boosters into these more vulnerable populations will really improve the overall effectiveness of the vaccines and cut down on the number of infections that we see.

Frederica Freyberg:

Now, we know that the FDA and CDC is now allowing mixing and matching of these vaccines and early reports suggest that the Johnson & Johnson vaccines which 270,000 people in Wisconsin received is far less protective even with its booster. So do you think boosting with an mRNA vaccine should be the choice for people in that category with the J & J?

William Hartman:

Following the data, both here in the United States and worldwide, it does appear that would be very appropriate to follow up the J & J vaccine with one of the mRNA vaccine. The data shows that when J & J was followed up with Pfizer, the antibody levels increased by 42 times. When it was followed up with Moderna, that antibody level increased by 75 times. So it greatly enhances the overall effectiveness and protection that these vaccines can convey.

Frederica Freyberg:

Okay. Dr. Hartman, thanks very much. We know these boosters are just rolling out as we speak. Thank you for your work and thanks for your time.

William Hartman:

Thank you for having me.