LULU GARCIA-NAVARRO, HOST:
Coronavirus vaccine trials are now underway for children as young as 12 years old in the United States. The available ones were only tested on people over 16 years of age. Scientists say vaccinating children is essential to ending this pandemic. Dr. Cody Meissner is chief of pediatric infectious diseases at Tufts Children's Hospital and a member of the FDA's vaccine advisory committee. We've reached him in Boston.
Welcome to the program.
CODY MEISSNER: Good morning, Lulu, and thank you very much for the invitation.
GARCIA-NAVARRO: It is a pleasure to have you. Please explain to us why children were not included in the original trials.
MEISSNER: First of all, what's the burden of disease in children? Hospitalization rates due to COVID-19 infection are a fraction of what they are in older age groups, and mortality rates are over a thousand times higher in individuals who are 75 years of age or older than they are in children and adolescents who are 5 to 17 years of age.
GARCIA-NAVARRO: One of the questions that was raised early on is about multi-inflammatory syndrome in children, MIS-C. That's the rare syndrome in children that develops post-COVID when a child has been infected and then an overactive response to the COVID infection sort of takes over the body. And there is a multi-inflammatory syndrome that develops. There were worries about a vaccine triggering that in some kids. Is that something that you are worried about?
MEISSNER: MIS-C seems to be a specific illness that develops about three weeks after an acute infection, and it may be that certain individuals have a genetic predisposition. And the concern was, might widespread use of this vaccine result in MIS-C? I think there's no evidence of that in adults, and it's unlikely that that will happen in children. But that's why I think people are being very circumspect about studying children. We want to do one age group at a time and then move down as we demonstrated safety.
GARCIA-NAVARRO: Dr. Meissner, knowing that this is going to take a while, it is probable that I will get vaccinated, the adults in my family will be vaccinated before my own child will be vaccinated. Can I travel with my child? Can my child see her vaccinated grandparents once all the adults are vaccinated, or will we still have to be in a holding pattern until children as well can be immunized?
MEISSNER: You know, this is primarily a disease that children catch from adults. And so once we generate sufficient so-called herd immunity so that enough adults have developed immunity from their vaccine or from an actual infection - and we think that something around 15- to 25% of the country right now is seropositive, meaning they have some degree of immunity - then maybe that will reduce the risk for children. But I think once the adults are immunized, I don't think children are going to play a big role in transmission to people who aren't. And I don't think...
GARCIA-NAVARRO: So the answer is yes. I could ostensibly take my child to see her family - her immunized family at some point.
MEISSNER: Yes. Now, I have to put an asterisk (laughter) 'cause this virus is tricking us with every twist and turn. First of all, how long will immunity last from the vaccine in the grandparents, as well as in children? As we're saying, it may be necessary to immunize on an annual basis, just as we do against influenza virus, as if there is waning immunity. And that's what happens with the seasonal coronaviruses, which we've known about for decades. And so we don't really know yet.
GARCIA-NAVARRO: That is Dr. Cody Meissner, chief of pediatric infectious diseases at Tufts Children's Hospital.
Thank you very much. Transcript provided by NPR, Copyright NPR.