>> Hi, my name is Paul Offit. I'm talking to you today from the Vaccine Education Center
at the Children's Hospital of Philadelphia. It is Tuesday, November 16th, 2021. When the mRNA
vaccines were first tested and presented to the Food and Drug Administration in December
of last year, those studies were, in the case of Pfizer, studies of about 40,000 adults, half
of whom got vaccine, half of whom got placebo. And in the case of Moderna, about 30,000 adults,
half of whom got vaccine, half of whom got placebo. So, in the case of Pfizer, there
were roughly 20,000 adults who got vaccine. In the case of Moderna, about 15,000 adults got vaccine.
What wasn't seen in any of those trials was a serious side effect. However, when these vaccines
were then given not to millions, but tens of millions and hundreds of millions of people,
a very, very rare side effect emerged, called myocarditis, which literally means inflammation
of the heart muscle. It was rare. Depending on what age you were looking at, it was between 1 in
20,000 to 1 in 50,000. It was that rare. But for the younger male who got the second dose,
say as an 18-year-old, 19-year-old, it could be as high as 1 in 10,000. So, for that reason, people
are concerned, reasonably, about myocarditis. Now, the good news about myocarditis,
at least following a vaccine, is that it tends to be very short-lived, transient and self-resolving.
It's not like what we think of as typical viral myocarditis. So, typical
viral myocarditis caused by viruses that have names like coxsackievirus can be quite severe,
invariably resulting in a hospital admission, often resulting in intensive care unit admission,
and also about 5 to 10% of the time resulting in the necessity for a heart transplant. That's not
this. In some ways I wish we didn't call it myocarditis because when you hear that term,
it makes physicians certainly think of this other sort of classic myocarditis that's caused by
viruses. That's not this. This is a short-lived phenomenon.
Now, you should also know that the virus itself, SARS-CoV-2, COVID, is associated with myocarditis.
There was a study done in athletes in the Big Ten conference, so these are sort of
older adolescents/young adults who had COVID. And what they did was they did a very sensitive
heart imaging study on every one of those people, independent of whether or not they had heart
symptoms. And they found that roughly 2.5% of that group, so roughly 1 in 45, who were infected with
the virus had evidence of myocarditis. Also remember MIS-C, this multisystem inflammatory
disease is also a cause of myocarditis about half the time or as much as 75% of the time. And in
those two cases, meaning the myocarditis caused by the virus or myocarditis caused by this MIS-C,
which is a post-infectious inflammatory phenomenon associated with COVID, is more severe than that
caused by the vaccine. So, there are no risk-free choices. A choice to get a vaccine is a much less
serious risk. And we know now that for the 12- to 15-year-old, the risk of myocarditis appears to be
less than it was say for the 16- to 25-year-old. And remember the 5- to 11-year-old is getting a
dose that’s only one-third of that that was given to the 12- to 15-year-old. So, the suspicion is
then, or the prediction is that the incidence of myocarditis would be even rarer in that group.
But I think parents should take heart in the fact that this myocarditis phenomenon appears to
be short-lived, transient and self-resolving and nothing like the myocarditis, classic myocarditis,
we saw with typical viral infections. Thank you.